DPP 6 embryonic devlopment

DPP 6 embryonic devlopment

  1. Holoblastic equal cleavage occurs in


(a) Insects (b) Frog (c) Birds (d) Mammals

  1. During cleavage all divisions are


(a) Equal (b) Reductional (c) Mitotic (d) Determinate

  1. The type of blastula formed in birds is


(a) Teloblastula (b) Holoblastula (c) Coeloblastula (d) Discoblastula

  1. Blastocoel, used as yolk space in other vertebrates, possesses in mammals


(a) Yolk (b) Fat reserve (c) Outer cell mass (d) Trophoectoderm

  1. Meroblastic cleavage is found in


(a) Bird (b) Frog (c) Lancet (d) Mammal

  1. The hollow ball of cells formed from cleavage is called the


(a) Gastrula (b) Morula (c) Blastula (d) Neurula

  1. Development of fertilized egg starts from


(a) Invagination (b) Fragmentation (c) Regeneration (d) Cleavage

  1. Blastopore is


(a) The opening of neural tube (b) Found in blastula (c) Present at future anterior end of embryo (d) The external opening of archenteron

  1. Superficial blastula is found in


(a) Rabbit (b) Cockroach (c) Chick (d) Frog

  1. Embryogenesis begins from


(a) Cleavage (b) Involution (c) Emboly (d) Gastrulation

  1. When cleavage furrow passes through the centre of animal vegetal axis, cleavage is


(a) Meridional (b) Vertical (c) Equatorial (d) Latitudinal

  1. Spiral cleavage occurs in


(a) Rabbit (b) Starfish (c) Earthworm (d) Frog

  1. What is true of cleavage


(a) There is no growth of daughter cells (b) Cytoplasm of blastomeres increases after each division (c) Daughter cells or blastomeres grow in size equal to parent cell (d) Blastomeres separate

  1. A cell formed from cleavage is called a


(a) Blastomere (b) Morula (c) Neurula (d) Blastula

  1. During cleavage one of the following remain same


(a) Size of egg (b) Volume of the egg (c) Both (d) None of the above

  1. Cleavage in Hydra is


(a) Radial (b) Bilateral (c) Asymmetrical (d) None of the above

  1. Spiral and determinate type of cleavage occurs in


(a) Ascaris (b) Mollusca (c) Frog (d) Both (a) and (b)

  1. Spiral and determinate cleavage is common amongst


(a) Amphibia (b) Nematoda, annelids, mollusc (c) Amniotes (d) Mollusca and amphibia

  1. Cell division in zygote is called


(a) Cleavage (b) Segmentation (c) Cellulation (d) All the above

  1. Fate mape of embryo is prepared in which stage


(a) Morula (b) Blastula (c) Gastrula (d) Neurula

  1. Patterns of cleavage

(a) 2-types (b) 5-types (c) 4-types (d) 3-types

  1. Who first prepared fat map of blastula by vital staining


(a) Vogt (b) Bismark (c) Von Baer (d) Spellanzani

  1. Preparation of cell differentiation are completed in


(a) Morula (b) Blastula (c) Gastrula (d) Neurula

  1. What happens in embryo during cleavage


(a) Decrease in cytoplasm and increase in nuclear material (b) Increases in cytoplasm and decrease in nuclear material (c) Decrease in both (d) Both remains constant

  1. The blastula is mostly a


(a) Double layered embryo without cavity (b) Triple layered embryo enclosing a cavity (c) Double layered embryo enclosing a cavity (d) Hollow spherical uniepithelial thick embryo

  1. The size of blastomere is


(a) Equal to a normal body cell (b) Much smaller than a body cell (c) Variable in individuals (d) More than body cell

  1. As a result of oblique cleavage the symmetry produced is known as


(a) Radial (b) Biradial (c) Spiral (d) Bilateral

  1. Which of the following is correct statement

(a) In blastulation major presumptive and organ forming areas are segregated into definite points of the blastoderm

(b) Blastulation establishes the three germinal layers

(c) Blastulation of frog is known as discoblastula


(d) Fluid filled space in blastula is known as archenteron

  1. Implantation is the process of


(a) Fertilization of egg (b) Movement of egg (c) Degeneration of egg (d) Attachment of blastocyst to the uterine wall

  1. The solid mass of cells formed at the end of cleavage of mammalian egg is


(a) Blastula (b) Morula (c) Blastocyst (d) Blastodisc

  1. The development of eye in vertebrate embryology is studied under

(a) Notogenesis (b) Neurogenesis (c) Mesogenesis (d) Organogenesis

  1. The concept that organiser is essential for embryonic development was given by or For the ‘theory of organiser’. Nobel prize was given to


(a) J. Axelrod (b) C. Landsteiner (c) H. Spemann (d) I. P. Pavlov

  1. The rate of cleavage is inversely proportional to the duration of


(a) Anaphase (b) Metaphase (c) Interphase (d) Telophase

  1. Which of the following structure is found in blastula

(a) Segmentation cavity (b) Notochord (c) Gill (d) Tail

  1. In which of the following animal cleavage divisions are restricted to a small part of cytoplasm and nucleus in animal pole of egg


[RPMT 2002] (a) Cockroach (b) Frog (c) Chick (d) Rabbit

  1. Select the correct statement


(a) Cleavage follows gastrulation (b) Yolk content of egg has no role in cleavage (c) Cleavage is repeated mitotic division of zygote (d) Gastrulation and blastulation are followed by each other

  1. Cleavage is unique form of mitotic cell division in which


(a) The nucleus does not participate (b) There is no growth of cells

(c) No spindle develops to guide the cells (d) The plasma membranes of daughter cells do not separate

  1. Holoblastic cleavage may occur in eggs which are


(a) Oligolecithal only (b) Mesolecithal only (c) Macrolecithal only (d) Oligolecithal and mesloecithal both

  1. As a result of cleavages, if blastomeres are symetrically placed around the polar axis the type of cleavage is known as


(a) Spiral (b) Discoidal (c) Biradial (d) Radial

  1. Meroblastic cleavage refers to one of the following types of division of eggs


(a) Total (b) Partial (c) Spiral (d) Horizontal

  1. The ratio of the nucleus to cytoplasm at the beginning of cleavage is


(a) Very low (b) Very high (c) Normal (d) A bit higher than the normal

  1. A blastula which is solid, is known as


(a) Stereoblastula (b) Coeloblastula (c) Superficial blastula (d) Discoblastula

  1. When are the identical twins born

(a) One sperm fertilizes two ova


(b) One ovum is fertilized by two sperms (c) Two ova are fertilized (d) One fertilzed ovum divides into two blastomeres and both of them separate

  1. Which of the following is true about cleavage in the fertilized egg in humans


(a) It is meroblastic (b) It is identical to the normal mitosis (c) It starts when the egg reaches uterus (d) It starts while the egg is in fallopian tube

  1. During the fourth and sixth cleavage of the zygote


(a) Mesomeres give rise to endoderm (b) Micromeres give rise to ectoderm (c) Mesomeres give rise to mesoderm (d) Macromeres give rise to ectoderm

  1. Periblastula is found in


(a) Man (b) Insects (c) Sycon (d) Reptiles

  1. In which of the following animals is a discoblastula stage found


(a) Star fish (b) Frog (c) Bird (d) Insect

  1. The term blastocyst is applied to the blastula of which one of the following


(a) Kangaroo (b) Platypus (c) Monkey (d) Both kangaroo and monkey

  1. In indeterminate cleavage the fate of blastomeres is fixed at which of the following stage


(a) Blastula (b) Gastrulation (c) 32-celled stage (d) 64-celled stage

  1. The fluid filled in the blastocoel cavity of blastula is


(a) Acidic (b) Albuminous (c) Saline (d) Pure water

  1. Embryologists can presume the future organs of the embryo in

(a) Blastula (b) Early gastrula (c) Morula (d) Post gastrula

  1. Which of these sets of cells divide slowly


(a) Micromeres (b) Megameres (c) Blastomeres (d) Mesomeres

  1. Fraternal twins in man are produced when

(a) Two sperms fertilize an ovum and the first two blastomeres separate from each other

(b) One sperm fertilizes an ovum and first two blastomeres separate from each other

(c) Egg develops parthenogenetically and first two blastomeres separate from each other


(d) Two ova are fertilized simultaneously

  1. Which of the following is not evident that the pattern of cleavage is determined by factors in the egg cytoplasm rather than by genes of zygote


(a) Cleavage is prevented by injection of a protein synthesis inhibitor (b) Cleavage is not affected by injection of inhibitors of RNA synthesis into the zygote (c) Interspecific hybrid zygotes go through normal cleavage but die at the beginning of gastrulation (d) The direction of the first division of cleavage in the snail Cepaea is determined by the mothers genotype (maternal effect)

  1. In a mesolecithal egg, one would expect


(a) Meroblastic cleavage (b) Unequal holoblastic cleavage (c) Equal holoblastic cleavage (d) None of the above

  1. Meridional cleavage results in blastomeres numbering


(a) 8 (b) 4 (c) 10 (d) 16

  1. Blastodisc or germinal disc refers to the protoplasm of egg, this is restricted to small area in


(a) Amphibian egg (b) Avian egg (c) Ascidian egg (d) Mammalian egg

  1. Which one of the following statements with regard to embryonic development in humans is correct

(a) Cleavage division bring about considerable increase in the mass of protoplasm

(b) In the second cleavage division, one of the two blastomeres usually divides a little sooner than the second

(c) With more cleavage divisions, the resultant blastomeres become larger and larger


(d) Cleavage division results in hollow ball of cells called morula

  1. Which is incorrect


(a) Fertilization occurs in fallopian tube (b) Fertilization is physico chemical event (c) Cleavage leads to increased mass of protoplasm (d) Cleavage produces morula

  1. Assertion. Holoblastic cleavage with almost equal sized blastomeres is characteristic of placental mammal.


Reason. Eggs of most mammals including humans are centrolecithal

(a) Point out if both are true with reason being correct explanation (b) Both correct but reason is not correct explanation (c) Assertion true but reason wrong (d) Both are wrong

  1. During cleavage


(a) Size of resulting cells decreases (b) Size of resulting cells increases (c) Size of early embryo increase (d) Size of early embryo decreases

  1. Assertion. In morula stage the cell divides without increase in size.


Reason. Zona pellucida remains till cleavage is finished

(a) Point out if both are true with reason being correct explanation (b) Both correct but reason is not correct explanation (c) Assertion true but reason wrong (d) Both are wrong

  1. Nereis has


(a) Stereoblastula (b) Discoblastula (c) Coeloblastula (d) Superficial blastula

  1. During cleavage, nucleocytoplasmic ratio (nucleus/ cytoplasm)


(a) Increases (b) Decreases (c) Remains same (d) None of the above

  1. Monozygotic twins are produced when


(a) Two ova are fertilized simultaneously (b) Incomplete cleavage of zygote

(c) First cleavage of zygote is followed by separation into two (d) There is no cleavage

  1. Mosaic cleavage occurs in


(a) Camel (b) Dog fish (c) Whale (d) Echinococcus

  1. In embryo, cleavage brings about


(a) Increased DNA content (b) Increased mass of protoplasm (c) Increased size (d) Change in shape and size

  1. The neurenteric canal opens to the outside by


(a) Mouth (b) Blastopore (c) Neuropore (d) None of these

  1. Cleavage differs from mitosis because


(a) In cleavage there is no growth phase (b) In cleavage consumption of increases (c) In cleavage nucleas-cytoplasmic ratio increases (d) All the above 2

  1. Which of the following is incorrect


(a) Fertilization is a physicochemical event (b) Cleavage of fertilized ovum results in blastula (c) Fusion of sperm and ovum occurs in fallopian tube (d) Cleavage leads to increase in the mass of protoplasm

  1. Spiral cleavage is observed in


(a) Frog (b) Fish (c) Turbellaria (d) Hydra

  1. Which three features are characteristic of protostome


(a) Spiral cleavage, indeterminate cleavage and schizocoely (b) Spiral cleavage, indeterminate cleavage and enterocoely (c) Spiral cleavage, determinate cleavage and enterocoely (d) Spiral cleavage, determinate cleavage and schizocoely

  1. In which type of cleavage, do the cleavage furrow divide a small amount of active cytoplasm at the animal pole


(a) Meroblastic (b) Holoblastic (c) Determinate (d) Unequal holoblastic

  1. Meroblastic cleavage occurs during the development of


(a) Human (b) Pigeon (c) Frog (d) Dogfish

  1. In centrolecithal eggs. The cleavage is


(a) Equal holoblastic (b) Unequal holoblastic (c) Meroblastic discoidal (d) Meroblastic superficial

  1. Cleavage differs from mitosis in that


(a) It occurs in all body cells (b) It occurs in zygote (c) It results into identical daughter cells (d) It occurs only in vertebrates

  1. During cleavage, the cell division is very rapid. The daughter cells do not undergo any growth and the cells thus become gradually smaller in volume. Hence


(a) There is no growth in the volume of the embryo (b) The embryo grows in volume (c) The embryo becomes smaller in volume (d) The embryo remains static

  1. Which is mismatched


(a) Coeloblastula – Amphioxus (b) Stereoblastula- Neries (c) Discoblastula-Birds (d) Amphiblastula-Reptiles

  1. Cleavage can be inhibited by


(a) Decrease in oxygen (b) Increase in (c) Colchicine (d) All the above 2

  1. Rate of cleavage is inversely proportional to amount of yolk it is called


(a) Baer’s law (b) Balfour’s law (c) Sach’s law (d) Hertwig’s law

  1. The first reported cleavage in mammalian egg was made in 1838 by


(a) Swammerdam and Spallanzani (b) Von Baer and Spallanzani (c) Prevost and Dumas (d) Leeuwenhoek

  1. The attachment of the mammalian blastocyst to the uterine wall is

(a) Incest (b) Implantation (c) Intromission (d) Incorporation

  1. An avian blastula is called


(a) Blastocyst (b) Trophoblast (c) Blastoderm (d) Foetal blastula

  1. Implantation of blastocysts occur on

(a) 4th day (b) 5th day (c) 6th day (d) 7th day

  1. The branch of embryology which concerns with the study of abnormal embryonic development is termed as

(a) Gerantology (b) Teratology (c) Embryology (d) None of the above

  1. Fertilised ovum is transplanted in uterus after


(a) 1 day (b) 7 days (c) 8 days (d) 10 days



  1. During the development of an embryo, migration and rearrangement of cells lead to a pattern formation known as

(a) Epiboly (b) Emboly (c) Involution (d) Gastrulation

  1. From which embryonic structure develops the vertebral column

(a) Neural canal (b) Archenteron (c) Notochord (d) Blastocoel

  1. The endodermal derivatives includes


(a) Thyroid (b) Pineal gland (c) Spleen (d) Pituitary

  1. Relative sizes of an egg cell, morula, blastula and gastrula are


(a) Egg cell is largest and morula is smallest (b) Egg cell is smallest and gastrula is largest (c) Egg cell is largest and gastrula is smallest (d) All are of equal size

  1. In which stage of development the embryonic cells form the germinal layers by the movement


(a) Morula (b) Blastula (c) Gastrula (d) Neurula

  1. Skeletal muscle develops from

(a) Ectoderm (b) Mesoderm (c) Endoderm (d) All the above

  1. In vertebrates the nails are formed from


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Ecto-mesoderm

  1. Nervous system in vertebrates develops from


(a) Endoderm (b) Ectoderm (c) Mesoderm (d) Endoderm and mesoderm both

  1. Gonads are derived from embryonic


(a) Mesoderm (b) Endoderm (c) Ectoderm (d) Mesoderm and endoderm

  1. Spleen develops from


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) None of the above

  1. Neural canal develops from


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) All the above

  1. Development of structure and shape of an organism is


(a) Morphology (b) Multiplication (c) Morphogenesis (d) Budding

  1. The blastopore develops into future


(a) Mouth (b) Ear (c) Anus (d) Neuropore

  1. The yolk plug of gastrula represents in the later stage its


(a) Anterior end (b) Posterior end (c) Dorsal side (d) Ventral side

  1. From which layer of the embryo do the liver and pancreas develop


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Both (a) and (c)

  1. The structure which differentiate gastrula from blastula


(a) 3 germ layers (b) Micromeres (c) Blastocoel (d) None of the above

  1. Which one of the following list contains only the mesodermal structures


(a) Muscles, blood, notochord, liver (b) Bones, blood, heart, liver (c) Muscles, blood, heart, liver (d) Bones, blood, heart, notochord

  1. In which order, three germ layers appear in the development

(a) Ectoderm- mesoderm-endoderm (b) Ectoderm-endoderm- mesoderm (c) Mesoderm- endoderm-ectoderm (d) None of the above

  1. In the first phase of gastrulation of amphibians there occurs the separation of


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Mesoectoderm

  1. Internal ear develops from


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) None of the above

  1. Which cavity arises by the invagination of endoderm and mesoderm


(a) Coelenteron (b) Archenteron (c) Pseudocoel (d) Coelom

  1. The epidermis of the skin is derived from the germinal layer


(a) Mesoderm (b) Endoderm (c) Ectoderm (d) Neuro-endoderm

  1. During gastrulation ….. is formed


(a) Heart (b) Gill (c) Archenteron (d) Vitelline membrane

  1. The only human system that is derived from all the three germ layers is


(a) Digestive system (b) Excretory system (c) Respiratory system (d) Nervous system

  1. The formation of the notochord takes place by


(a) Primary ectoderm (b) Primary mesoderm (c) Primary endoderm (d) None of the above

  1. The outer layer of the blastocyst which forms the ectoderm is called


(a) Cnidoblast (b) Germinal vesicle (c) Trophoblast (d) Amnion

  1. Which of the following is correct


(a) Mesoderm produces brain (b) Ectoderm produces liver (c) Mesoderm produces skeleton (d) Endoderm produces heart

  1. Which of the following develops from ectoderm


(a) Spinal cord and brain (b) Liver and heart (c) Notochord and vertebral column (d) Eye and skin

  1. Formation of notochord or the central axial chord in vertebrates is known as


(a) Neurulation (b) Blastulation (c) Morulation (d) Notogenesis

  1. The rolling of endodermal and mesodermal cells from the surface of embryo into its interior is called


(a) Ingression (b) Invagination (c) Involution (d) Inversion

  1. Gastrulation is the process which involves the differentiation of the following layers in a vertebrate embryo


(a) Ectoderm and mesoderm (b) Ectoderm and endoderm (c) Endoderm and mesoderm (d) Ectoderm, endoderm and mesoderm

  1. The skeleton and muscles originate in the development from or During embryonic development endoskeleton and muscles develop from which germinal layer


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) Yolk plug

  1. The nerve cells, brain and spinal cord or central nervous system develops from embryonic


 (a) Ectoderm (b) Endoderm (c) Mesoderm (d) Both (a) and (b)

  1. Ontogenetically liver and pancreas are or During embryonic development pancreas and liver develop from which germinal layer


 (a) Ectoderm (b) Mesoderm (c) Endoderm (d) Blastopore

  1. Mesoderm gives rise to all the structures except


(a) Nervous system (b) Muscular system (c) Circulatory system (d) Gonads

  1. The primordial germ cells make their appearance from wall of


(a) Amnion (b) Chorion (c) Allantois (d) Gonad

  1. Brain originates from which germ layer

(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Ectomesoderm

  1. Which is the correct sequence in the development of man


(a) Fertilization, zygote, cleavage, morula, blastula, gastrula (b) Zygote, morula, blastula, differentiation (c) Fertilization, cleavage, gastrula, morula, blastula (d) Cleavage, zygote, blastula, morula, gastrula

  1. The period of preparation with reference to developmental phenomena in vertebrates means


(a) Formation of gastrula (b) Formation of germ layers (c) Tissue differentiation (d) Parents preparation and elaboration of gametes

  1. Among the following who is regarded to be the founder of modern embryology


(a) Aristotle (b) Newport (c) Von Baer (d) Spallanzani

  1. The cavity of gastrula is called


(a) Blastocoel (b) Coelom (c) Archenteron (d) Haemocoel

  1. Amniotic fluid is found in


(a) Uterus (b) Scrotal sac (c) Kidney (d) Liver

  1. Emboly is

(a) Migration of micromeres into the blastocoel


(b) Migration of macromeres into the blastocoel

(c) Migration of endoderm, mesoderm and notochord in the blastocoel


(d) None of the above

  1. The origin of germ layers in chick embryo was described by


(a) Hans speman (b) Pander (c) Charles Bonnet (d) None of the above

  1. Primary germ layers are


(a) Trophoblast, ectoderm, mesoderm and endoderm (b) Endoderm, trophoectoderm and trophomesoderm (c) Trophomesoderm and trophoectoderm (d) Ectoderm, mesoderm and endoderm

  1. Pancreas is


(a) Ectodermal (b) Mesodermal (c) Endodermal (d) None of the above

  1. Kidneys are


(a) Ectodermal (b) Mesodermal (c) Endodermal (d) None of the above

  1. Splanchnocoel is


(a) Haemocoel (b) Pseudocoel (c) True coelom (d) Pseudocoelom

  1. The organ not formed by ectoderm is


(a) Brain (b) Spinal cord (c) Internal ear (d) Gonads

  1. Which is formed first


(a) Primitive gut (b) Ectoderm (c) Mesoderm (d) Endoderm

  1. Part of primitive gut is


(a) Yolk sac (b) Embryonic disc (c) Trophoblast (d) Inner cell mass

  1. Which is not formed by endoderm


(a) Pancreas (b) Kidneys (c) Liver (d) Lungs

  1. Nerves develop from


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Both layers of mesoderm and endoderm

  1. Morphogenetic movements occur in


(a) Cleavage stage (b) Morula (c) Blastula (d) Gastrula

  1. The hypoblast (inner germ layer of gastrula) forms the


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) None of the above

  1. The epiblast (outer germ layer of gastrula) forms the


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) None of the above

  1. Heart is


(a) Ectodermal (b) Mesodermal (c) Endodermal (d) None of these

  1. During gastrulation is formed


(a) Notochord (b) Nerve cord (c) Myotome (d) Archenteron

  1. Skeleton and muscles originate from


(a) Yolk plug (b) Mesoderm (c) Endoderm (d) Ectoderm

  1. In which organ the bulk is formed of endoderm


(a) Intestine (b) Liver (c) Heart (d) Kidney

  1. Alimentary canal is derived from


(a) Endoderm (b) Ectoderm (c) Mesoderm and endoderm (d) Ectoderrn and endoderm

  1. Which one develops from mesoderm


(a) Testes and pancreas (b) Nervous system and skeleton (c) Sense organs and muscles (d) Blood vessels and excretory organs

  1. Sensory receptors, such as retina, develop from


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) Mesoderm and endoderm

  1. True coelom is lined by


(a) Mesoderm (b) Mesoderm and ectoderm (c) Endoderm (d) Ectoderm

  1. In development, Eustachian tube is

(a) Ectodermal (b) Mesodermal (c) Endodermal (d) Both mesodermal and endodermal

  1. Retina, eye lens, brain and skin are formed from


(a) Mesoderm (b) Ectoderm (c) Endoderm (d) Both ectoderm and endoderm

  1. Blastopore is


(a) Opening of neural tube (b) Opening of gastrocoel (c) Future anterior end of embryo (d) Found in blastula

  1. Archenteron begins forming in

(a) Early gastrula (b) Late gastrula (c) Early morula (d) Blastula

  1. Olfactory epithelium develops from


(a) Embryonic endoderm (b) Embryonic ectoderm (c) Embryonic mesoderm (d) Embryonic mesenchyme

  1. Notochord grows form


(a) Neuropore (b) Prechordal plate (c) Hypochordal rod (d) Chorda-mesoderm

  1. Which one is not formed from ectoderm

(a) Notochord (b) Epidermis (c) Internal ear (d) Adrenal medulla

  1. Which is derived from ectoderm


(a) Epidermis (b) Spinal cord (c) Retina (d) All the above

  1. The proctodaeum develops from


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) None of the above

  1. Intestine develops form


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) Pharyngeal pouch

  1. Early embryonic stage that follows blastula is


(a) Morula (b) Amphiblastula (c) Radula (d) Gastrula

  1. Rearrangement of layers occurs during

(a) Gastrulation (b) Blastulation (c) Morulation (d) Organogenesis

  1. Morphogenetic movements convert hollow spherical blastula into


(a) Gastrula (b) Morula (c) Neurula (d) Embryonic disc

  1. Which one develops from ectoderm


(a) Adrenal medulla (b) Adrenal cortex (c) Blood (d) Lymph

  1. When do the three germinal layers differentiate


(a) Blastula (b) Gastrula (c) Cleavage (d) Fertilization

  1. Which one is produced by mesoderm


(a) Heart and notochord (b) Heart and brain (c) Spinal cord and notochord (d) Brain and notochord

  1. In mammals, the body of embryo is formed from


(a) Trophoblast (b) Trophoectoderm (c) Outer cell mass (d) Inner cell mass

  1. The mesoderm in chick embryo gives rise to all of the following organs except the

(a) Brain (b) Heart (c) Kidney (d) Skeleton

  1. Which of the following is not ectodermal

(a) Inner ear (b) Optic nerve (c) Middle ear (d) Epithelial tissue

  1. Study of different phases of development of organ is known as


(a) Histogenesis (b) Pathogenesis (c) Morphogenesis (d) Embryogenesis

  1. Which of these in frog develops from mesoderm

(a) Spleen (b) Eye lens (c) Adrenal medulla (d) Thyroid gland

  1. Nephrogenous tissues are derived from embryonic

(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Two of these

  1. Endoderm in a mammalian embryo is formed by


(a) Epiboly (b) Ingression (c) Delamination (d) Invagination

  1. Which of the following organs develops first


(a) Liver (b) Notochord (c) Heart (d) Kidney

  1. In rabbit, the blastopore develops into future


(a) Anus (b) Mouth (c) Neuropore (d) Notochord

  1. Theory of germ layers in the embryo was first proposed by


(a) De Graaf (b) Harvey (c) Haeckel (d) Von Baer

  1. In which stage rate of cell division decrease


(a) Morula (b) Gastrula (c) Blastula (d) Zygote

  1. Which statement is not correct for gastrulation


(a) Formation of archenteron (b) Cell division stops (c) Oxidation reaction increase (d) Elongation of embryo starts

  1. The first indication of division of labour in the blastomeres appear at


(a) Morula stage (b) Blastula stage (c) Gastrula stage (d) Neurula stage

  1. Gastrulation is a process


(a) Which begins the segregation of germ layers (b) That occurs just after blastulation (c) That occur just after cleavage (d) Of rapid growth in blastomeres

  1. A definate polarity such as dorsoventral and antero posterior can be recognised at


(a) Morula stage (b) Gastrula stage (c) Blastula stage (d) Zygote stage

  1. Mass separation of cells during gastrulation is


(a) Epiboly (b) Emboly (c) Delamination (d) Differentiation

  1. One of these is not an ectodermal derivation


(a) Lens of eye (b) Dermis of skin (c) Entire nervous system (d) Epidermis of skin

  1. Blood is derived from


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) None of the above

  1. The mammalian primitive streak gives rise to


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Germ layers

  1. Rathke’s pouch is


(a) Rudimentary pouch of the ectoderm posterior to the last gill (b) A diverticulum from the buccal cavity in the embryo (c) Rudiment of pars nervosa (d) All the above

  1. Proctodaeum in rabbit is


(a) A part of large intestine lined by ectoderm (b) A part of large intestine lined by endoderm (c) A part of large intestine lined by mesoderm (d) Embryonic intestine

  1. Blastopore is found in


(a) Blastula and is opening of archenteron (b) Blastula and is opening of blastocoel (c) Gastrula and is opening of archenteron (d) Gastrula and is opening of blastocoel

  1. True coelom develops as a split in

(a) Mesoderm (b) Endoderm (c) Ectoderm (d) Between ectoderm and endoderm

  1. Pasteels (1945) described gastrulation takes place in aves by


(a) Infiltration (b) Delamination (c) Concrescence (d) Polyinvagination

  1. When mouth develops from blastopore, the organism is called


(a) Deutrostomia (b) Protostomia (c) Blastostomia (d) None of the above

  1. During the development of embryo which of the following occur first


(a) Differentiation of tissue (b) Differentiation of cells (c) Differentiation of organs (d) Differentiation of organ system

  1. If the ectoderm from neural tissue area is removed from the embryo and transplanted in place of presumptive belly ectoderm embryo will develop

(a) Without a neural tube (b) With a neural tube (c) With two ectodermal coats (d) With two neural tube

  1. In both chordates and non-chordates intestine develops from

(a) Pharyngeal pouch (b) Ectoderm (c) Endoderm (d) Mesoderm

  1. Coelom is found between the cavity of

(a) Ectoderm and endoderm (b) Mesoderm and ectoderm (c) Body wall and ectoderm (d) Mesoderm and body wall

  1. In the development of the human body, the ectoderm is responsible for the formation of


(a) Sweat glands (b) Nervous system (c) Lens of the eye (d) All the above

  1. True coelom is a space between the body wall and alimentary canal. It is lined by

(a) Mesoderm on one side and ectoderm on the other side (b) Endoderm on one side and ectoderm on the other side (c) Mesoderm on both the sides (d) Ectoderm on both the sides

  1. In mouth develops from which of the following


(a) Mesoderm (b) Ectoderm (c) Blastopore (d) Endoderm

  1. A phenomenon of embryonic induction was first described in amphibia by


(a) Aristotle (b) Spemann (c) Von Baer (d) Spallanzani

  1. During gastrulation the dorsal lip of blastopore (1 external sign of gastrulation) appears


(a) Anteriorly in the pigmented area of egg (b) Posteriorly in the yolky cytoplasmic area (c) In the centre of the egg (d) Behind the grey crescent area

  1. Archenteron is lined with (in frog)

(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Mesoderm and endoderm

  1. The literal meaning of “gastrulation” is


(a) Formation of primary germ layers (b) Formation of a gut (c) Morphogenetic movement (d) Commencement of organogenesis

  1. Termination of gastrulation is marked by


(a) Obliteration of archenteron (b) Closure of neural tube (c) Obliteration of blastocoel (d) All the above

  1. Epiboly is the process of

(a) Mass migration of cells from the animal hemisphere so that upper micromeres begin to migrate over the edge of the dorsal lip and roll inside and are tucked beneath the outer layer


(b) Over growth when the micromeres divide rapidly and begin to spread down wards over the megameres except at the yolk plug (c) Rotation of gastrula within the vitelline membrane so that the animal pole becomes anterior (d) Formation of a small slit like invagination occuring on the gray crescent

  1. Sex of the embryo in the uterus is determined by


(a) GIFT (b) Amniocentesis (c) Using X-chromosome killer cream (d) All the above

  1. Amniocentesis is a technique used for


(a) Estimating amino acid content in the amnion (b) Measuring size of the amnion (c) Determining sex of the foetus (d) Determining position of the foetus

  1. The yolk plug is a structure in gastrula which is formed by the protrusion of


(a) Endodermal cells (b) Endo-mesodermal cells (c) Ectodermal cells (d) Mesodermal cells

  1. Vascular system and excretory organs are developed from


(a) Mesoderm (b) Ectoderm (c) Endoderm (d) None of the above

  1. The central nervous system develops as a result of


(a) Metamorphosis (b) Gastrulation (c) Neurulation (d) Invagination

  1. Which of the embryo has parasite mode of nutrition


(a) Bird’s embryo (b) Amphibian embryo (c) Reptilian embryo (d) Mammalian embryo

  1. The aminotic fluid is taken out with the help of surgical needle and separation of the embryo cells present in this fluid is done by

(a) Amniotic fluid study (b) Amniocentesis (c) Centrifugation (d) None of the above

  1. By the amniocentesis, one of the following group can be possible to study

(a) Study of cytoplasmic behaviour


(b) Study of cellular organelles (c) Study of abonormal behaviour of chromosomes and physiological activities (d) Study of nature of embryo

  1. From the egg in gastrula stage if you remove all cells which form endoderm, the new organism will lack of


(a) Eyes (b) Heart (c) Eyes and brain (d) Some of the visceral organs

  1. The main function of tropho ectoderm in mammalian embryo is


(a) Protection of the developing cells (b) Drawing food for the developing cells (c) Formation of yolk sac (d) Formation of body of developing embryo

  1. During the course of development, cells in various regions of embryo become variable in morphology and eventually perform diverse functions. This process is known as

(a) Rearrangement (b) Differentiation (c) Metamorphosis (d) Organisation

  1. In vertebrates the central nervous system develops under the influence of


(a) Pituitary hormones (b) Phospholipids (c) Glycolipids (d) Phospholipids and glycolipids

  1. Blastopore is found in

(a) Gastrula (b) Blastula (c) Morula (d) Neurula

  1. Which one of the following is derived from ectoderm


(a) Enamel of teeth (b) Dentine (c) Skull (d) Axial skeleton

  1. The best definition of the process of gastrulation is that, it is a process where the

(a) Single layered blastula becomes two layered (b) Archenteron is formed (c) Cells move to occupy their definite position (d) Zygote gets converted to a larva

  1. After gastrulation the roof of archenteron is formed by


(a) Neural plate (b) Mesoderm (c) Ectoderm (d) Chorda- mesoderm

  1. Which of the following is not correct for gastrulation


(a) Archenteron is formed (b) All germinal layers are formed (c) Morphogenetic movements (d) Some blastomeres and blastocoel degenerate

  1. Which of the following structure originates from ectoderm


(a) Stomodaeum (b) Proctodaeum (c) Mesodaeum (d) Both (a) and (b)

  1. Match the items ABCD of table ‘A’ with that of items in table ‘B’ then the correct pairing sequence of ABCD will be


‘A’ ‘B’ A. Cleavage 1. Formation of 3 germ layers B. Gastrulation 2. Formation of embryo spinal cord C. Neurulation 3. Results in formation of skeleton and muscles from mesoderm D. Organogenesis 4. Pattern depends on the amount and distribution of yolk (a) 4, 1, 2,3 (b) 2, 3, 1, 4 (c) 4, 2, 3, 1 (d) 3, 1, 2, 4

  1. Mesoderm proliferates from


(a) Trophoblast (b) Cephalic end of embryonic disc (c) Caudal end of embryonic disc (d) Ectoderm of embryonic disc

  1. What is true of deuterostomes


(a) Presence of schizocoel (b) Nonformation of anus from blastopore (c) Coelom lined by mesoderm on both sides (d) Presence of false coelom

  1. During gastrulation blastomeres move from the surface to their destination in the embryo. These movements are called


(a) Migratory movements (b) Formation movements (c) Morphogenetic movements (d) All the above

  1. The medullary tube is formed by


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) None of the above

  1. Morphogenetic movements involve


(a) Movements of organs (b) Movement of small cell masses (c) Movement of large cells masses (d) Differentiation of cells

  1. If chorda mesoderm evaginates instead of invagination


(a) Only ectodermal and endodermal structures develop (b) Only mesodermal and endodermal structures develop (c) No development occurs (d) Only ectodermal and mesodermal structures develop

  1. Germinal layer formed from trophoblast of mammalian blastocyst is


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) None of the above

  1. Which one develops from endoderms


(a) Nervous system, urinary bladder and eye (b) Liver, connective tissue and heart (c) Thymus, spinal cord and brain (d) Liver, pancreas and thymus/ thyroid

  1. Sense organs are formed from


(a) Ectoderm (b) Mesoderm (c) Partly ectoderm and partly mesoderm (d) Endoderm

  1. Vascular tissue is derived from


(a) Epithelium (b) Ectoderm (c) All germinal layers (d) Mesoderm

  1. Two formative movements that take place during gastrulation are


(a) Involuation and invagination (b) Epiboly and emboly

(c) Invagination and ingression (d) Ingression and delamination

  1. In deuterostomes second opening forms


(a) Anus (b) Mouth (c) Nose (d) Both (a) and (b)

  1. Adrenal medulla and membranous labyrinth develop from


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) Both (b) and (c)

  1. Spreading of presumptive ectoderm on underlying mass of cell is


(a) Epiboly (b) Invagination (c) Ingression (d) Delamination

  1. Jaw bones are formed from


(a) Ectoderm (b) Endoderm (c) Mesoderm (d) Ectoderm and endoderm

  1. An organ not formed form ectoderm is


(a) Optic nerve (b) Middle ear (c) Inner ear (d) Skin

  1. Ganglia of sympathetic and other neural systems develop from


(a) Neural cell (b) Neural plate cells (c) Notochord cells (d) Neural crest cells

  1. Gastrulation comprises


(a) Morphogenetic movements (b) Differentiation of archenteron (c) Differentiation of three germ layers (d) All the above

  1. Study of formation of sensory organs is


(a) Organogenesis (b) Neurogenesis (c) Mesogenesis (d) Notogenesis

  1. In the fate map of early gastrula of frog, what is the correct sequence in which the three consecutive presumptive embryonic cell masses


line upon the axis lying perpendicular to the dorsal lip, counting from the same (a) Notochord, medullary plate, epidermis (b) Epidermis, medullary plate, notochard (c) Prechordal plate, notochord, mesoderm (d) Prechordal plate, notochord, medullary plate

  1. Formation of primitive streak in the chick embryo is the first sign of


(a) Blastulation (b) Gastrulation (c) Neurulation (d) Notogenesis

  1. During the development of frog, which one of the following sets of structures is derived from the endoderm


(a) Skin and skin glands (b) Pituitary and adrenal medulla (c) Kidneys and their ducts (d) Trachea, lungs, liver and pancreas

  1. The process by which the developing notochord causes dorsal ectoderm above it to form a neural plate is known as


(a) Induction (b) Invagination (c) Differentiation (d) None of the above

  1. Stage of embryonic development in which differentiation of cell occurs


(a) Neurula (b) Gastrula (c) Blastula (d) Morula

  1. Which of the following is correct grouping


(a) Ectoderm-Retina, epidermis, nervous system (b) Mesoderm-Ovary, urinary bladder, kidney (c) Mesoderm-Lungs, connective tissue, testis (d) Endoderm- Thyroid, pineal gland, thymus

  1. Somatopleur is combination of


(a) Ectoderm and endoderm (b) Mesoderm and endoderm (c) Mesoderm and ectoderm (d) None of the above

  1. Somite is part of


(a) Ectoderm (b) Mesoderm (c) Endoderm (d) Archenteron

  1. Vital dyes for fat mapping is


(a) Netural red (b) Nile blue sulphate (c) Bismarck brown (d) All the above

  1. Epiboly refers to morphogenetic or formative movements of prospective


(a) Ectodermal cell (b) Endodermal cell (c) Mesodermal cell (d) Chorda-mesodermal and endodermal cell

  1. Significance of gastrulation lies in the fact that

(a) It is the real starting point of the constructive of multi cellular body

(b) It initiates the formation of nervous system

(c) It brings presumptive areas into their normal position in the embryo


(d) All the above

  1. “Isthmus of pander” is located in


(a) In germinal vesicle (b) Below blastodisc (c) Between shell membrane (d) In chalaza

  1. If the chorda- mesoderm tissue formed from grey crescent is killed by boiling and an extract from this is placed on ectoderm it will


(a) Induce neural plate formation (b) Not induce neural-plate formation (c) Sometime induce mesoderm formation (d) All the above

  1. The lateral mesoderm splits to form visceral and parietal layer which encloses the


(a) Proctodaeum (b) Stomodaeum (c) Splanchnocoel (d) None of the above

  1. Trophoectoderm or trophoderm in embryonic development of mammals is formed at the stage of


(a) Blastocyst (b) Zygote (c) Morula (d) Gastrula

  1. Which of the following is not diploblastic


(a) Sponge (b) Cnidarian (c) Nematoda (d) Ctenophora

  1. The cavity formed during gastrulation is


(a) Archenteron (b) Gasterocoel (c) Primitive gut (d) All the above

  1. The term, ‘metaplasia’ refers to the process by which

(a) Differentiated cell is able to become transformed into a differentiated cell of another type

(b) Cell becomes differentiated

(c) Cell grows abnormally fast


(d) None of the above

  1. The process by which one part of a developing embryo influences the differentiation of other parts is known as


(a) Transduction (b) Induction (c) Metamorphosis (d) None of the above

  1. The somites which are metamerically segmented blocks of mesoderm differentiate into all of the following except


(a) Myotome which forms the muscles (b) Dermatome which forms the dermis (c) Sclerotome which gives rise to the axial skeleton (d) None of the above

  1. When a piece of tissue is able to respond to an organising substance by producing a definite tissue eg. neural plate ; the process is


(a) Induction (b) Competence (c) differentiation (d) None of the above

  1. Presumptive ectoderm is that

(a) Layer which presumabley is ectoderm


(b) Layer which may or may not develop into ectoderm (c) Area around the margin of the blastopore which rolls into the interior of the embryo thus forming the lining of the primitive gut (d) None of the above

  1. All the following structures are ectodermal except one which is mesodermal


(a) Epithelium of retina (b) Optic nerve (c) Eye lens (d) Outer eye layers

  1. Collection and dispersion of embryonic cells is called


(a) Differentiation (b) Induction (c) Morphogeneis (d) Blastomy

  1. The cells of the trophoblast in mammals which lie over the embryonic disc are known as


(a) Primitive streak (b) Hensen’s node (c) Cells of Rauber (d) None of the above

  1. Ingression is defined as


(a) The rolling movement of meso and endodermal cells (b) Insinking of meso and endodermal cells (c) Detachment of meso and endodermal cells in groups (d) None of the above


Extra embryonic membrane

  1. All extra embryonic membranes


(a) Take part in the formation of embryo (b) Does not take part in the embryo formation (c) Form the placenta (d) Perform the function of excretion of embryo

  1. Chorion is found


(a) Inside the amnion (b) Outside the amnion (c) Inside the allantois (d) Inside the yolk sac

  1. Middle gastrula is characterised by


(a) Formation of yolk plug (b) Archenteron just beings to form (c) Blastopore and archenteron are present (d) Yolk plug shifts towards blastopore

  1. The technique which makes use of amniotic fluid for the detection of prenatal disorders is called as


(a) Endoscopy (b) Laproscopy (c) Natal endoscopy (d) Amniocentesis

  1. Function of allantois in mammals is


(a) Respiration only (b) Excretion (c) Nutrition, excretion and respiration (d) Protection from shocks

  1. Mammalian embryo is directly surrounded by


(a) Amniotic cavity (b) Allantoic cavity (c) Primary digestive cavity (d) Yolk sac cavity

  1. Mammalian placenta has minute finger like projections called


(a) Chorionic villi (b) Chorionic network (c) Chorionic extensions (d) Chorionic plexus

  1. Foetal membranes provide


(a) Protection to embryo (b) Nutrition to embryo (c) Protection and nutrition to embryo (d) None of the above

  1. The extra-embryonic membranes of the mammalian embryo are derived from

(a) Formative cells (b) Follicle cells (c) Inner cell mass (d) Trophoblast

  1. Amnion helps in


(a) Respiration (b) Excretion (c) Nutrition (d) Protection from shocks

  1. Allantois develops from the embryonic


(a) Fore gut (b) Mid gut (c) Hind gut (d) Tail region

  1. The respiratory function of embryo is performed by


(a) Chorion (b) Amnion (c) Allantois (d) Yolk sac

  1. Urinary bladder of the embryo is or which is the urinary bladder of child placed in the womb


(a) Yolk sac (b) Allantois (c) Amnion (d) Chorion and allantois both

  1. The shock absorber fluid of the developing embryo is known as


(a) Chorionic fluid (b) Amniotic fluid (c) Allantoic fluid (d) Coelomic fluid

  1. The function of amniotic cavity is


(a) Respiration (b) Protection from desiccation and shocks (c) Protection from desiccation (d) Protection from shocks

  1. Number of foetal membranes in humans is


(a) 2 (b) 3 (c) 4 (d) 0

  1. Amniotes include


(a) Fishes, reptiles and amphibians (b) Amphibians, birds and reptiles (c) Birds, reptiles and mammals (d) Amphibians, reptiles and mammals

  1. Amnion surrounds


(a) Allantois (b) Chorion (c) Embryo (d) Yolk sac

  1. Villi of human placenta develop from


(a) Chorion (b) Allantois (c) Yolk sac (d) Both (a) and (b)

  1. Membrane that gives protection to embryo from external shocks is


(a) Amnion (b) Allantois (c) Chorion (d) Placenta

  1. Amniotic fluid protects the foetus from


(a) Shock (b) Encystment (c) Degeneration (d) Disease

  1. Foetal membranes produced by trophoblast are


(a) Chorion and allantois (b) Chorion and amnion (c) Amnion and allantois (d) Allantois and yolk sac

  1. In birds, allantois helps in


(a) Excretion (b) Respiration (c) Nutrition (d) Protection

  1. Allantois is extraembryonic membrane found in


(a) Reptiles (b) Birds (c) Mammals (d) All the above

  1. Yolk containing cytoplasm is called


(a) Ooplasm (b) Protoplasm (c) Deuteroplasm (d) Trophoplasm

  1. In the organisms having amnion, the foetal membranes are


(a) Zona pellucida, vitelline membrane (b) Allantois, chorion (c) Choroid, vitelline membrane (d) None of the above

  1. Which of the foetal membrane is directly connected with blood


(a) Allantois (b) Amnion (c) Chorion (d) Yolk sac

  1. Which of these is an extra embryonic membranes


(a) Henson’s line (b) Diencephalon (c) Allantois (d) Primitive streak

  1. In mammals since the ovum does not have yolk the yolk sac is


(a) Rudimentary (b) Absent (c) Sizeable through ovum has little yolk (d) None of the above

  1. The amnion and chorion consist of which type of composition


(a) Somatopleure (b) Splenchnopleure (c) Somatic mesoderm only (d) Somatic endoderm only

  1. The allantois has the similar layers as present in the yolk sac. These are


(a) Outer mesoderm and inner endoderm (b) Outer endoderm and inner mesoderm (c) Outer endoderm and inner ectoderm (d) Outer endoderm and inner endoderm

  1. In man the foetal membrane which forms the intimate connection with the uterine tissue is


(a) Amnion only (b) Chorion only (c) Allantois only (d) Allanto-chorionic structure

  1. Umbilical cord in mammals, contains


(a) Placenta (b) Umbilicus (c) Allantoic artery and vein (d) Discus poligerous

  1. Chorion is composed of


(a) Cytotrophoderm (b) Syncytial trophoblast (c) Outer ectoderm and somatic mesoderm (d) All of the above

  1. Extra embryonic membrane amnion is not found in amphibians because


(a) They lay eggs in water (b) Egg hatches in tadpole (c) Amphibious habit (d) They have smooth skin

  1. The embryo of man is protected by

(a) Amniotic cavity (b) Peritoneal cavity (c) Pleural cavity (d) Allantois

  1. In the development of man which structures are formed from splanchnopleure


(a) Muscles and connective tissue of digestive tube (b) Vertebral column and spinal cord (c) Brain and its coverings (d) Urinogenital organs

  1. The foetal membrane which is the source of first blood corpuscle to enter the circulation of the embryo is called


(a) Amnion (b) Chorion (c) Trophoblast (d) Yolk sac

  1. In early haemopoietic tissue of embryo, there is


(a) Chorion (b) Amnion (c) Allantois (d) Yolk sac

  1. In mammals the chorion and the allantois together form


(a) Placenta (b) Endometrium (c) Uterus (d) Yolk sac

  1. Which one of the following can be determined by amniocentesis


(a) Klinefelter’s syndrome (b) Turner’s syndrome (c) Sex of the unborn child (d) All the above

  1. Amniocentesis is

(a) An inutero diagnosis


(b) Withdrawl of allantoic fluid from pregnant woman (c) Anlaysis of chemical composition of fluids of pregnant woman (d) Culturing of cells and study of metaphase chromosomes from amniotic fluids to identify chromosomal abnormality

  1. Amnion is a membrane which develops on the outside of embryo in


(a) Fish (b) Cockroach (c) Toad (d) Lizard

  1. Match List-I (Foetal membrane in chick) with list –II (Function) and select the correct answer using the codes given below the lists
List I (Foetal membrane in chick) List II (Function)

A. Amnion

B. Chorion


C. Yolk sac

D. Allantois



1. Excretion

2. Protection against mechanical shock

3. Nutrition

4. Protection from desiccation

5. Absorption of water and albumen






























































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