Biology

Embryonic Development

621 Questions

Embryonic development questions cover the biological processes of gamete fusion, germ layer formation, and fetal maturation. The focus lies in identifying extraembryonic structures, trophoblast functions, and sequential developmental stages. This specialized topic appears regularly in biology screening tests and medical entrance examinations.

Germ layer formationBlastocyst implantationExtraembryonic structuresFetal development stagesReproductive physiology

Embryonic Development Questions

Multiple choice biology seeds - structure and germination dicot seed structure of monocot and dicot seed the seed monocot seed

In plants, during embryonic condition

  1. All cells of the embryo divide.

  2. Meristematic activity is confined to single apical cell.

  3. Meristematic activity is confined to a group of apical cells.

  4. Apical and lateral cells only divide.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Embryonic tissue in plants refers to the actively growing cells but more than often this term is used to describe the early formation of tissue during its first growth stages. It thus refers to the sporophyte, gametophyte embryos from seedlings as well as meristematic tissues which are always in embryonic state. Under this condition, the growth of this tissues takes place through cell division and the cells of the embryo divide.

Therefore, the correct answer is option A.

Multiple choice biology the flower dicot seed structure of monocot and dicot seed the seed

Caruncle is derived from

  1. Peduncle

  2. Cotyledon

  3. Outer integument

  4. Inner integument
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
In plants,Caruncle is an outgrowth near the hilum on the seeds of some plants of family Euphorbiaceae (like Hevea ). Outer integument is the outermost part of the ovule . During development of the ovule, the outer integument differentiates into different layers of seed coat. Caruncle is also derived from outer integument.
So, the correct option is 'Outer integument'
Multiple choice zoology nervous system of man major divisions of nervous system introduction to control and coordination neurons and synapses

The nervous system develop from which of the following primary germ layer?

  1. Endoderm

  2. Mesoderm

  3. Ectoderm

  4. Enteroderm

  5. Epidermis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Neural crest cells of ectoderm migrate downward to form the dorsal root ganglia of the spinal nerves and the postganglionic sympathetic neurons. The sensory cells in the dorsal root ganglia give rise to dendrites extending to sense organs and axons extending into the spinal cord. Some other neural crest cells form parts of certain sense organs and parts of the head. Few head derivatives of the neural crest give rise to sensory nerves and other parts of the peripheral nervous system and ganglia of the autonomic nervous system. Thus, the correct answer is option C.

Multiple choice zoology nervous system of man major divisions of nervous system introduction to control and coordination neurons and synapses

The central nervous system develops as a result of 

  1. Metamorphosis

  2. Gastrulation

  3. Neurulation

  4. Invagination
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Metamorphosis is the process by which an organism changes its form or habits during normal development after embryonic stage.
Gastrulation is the process, where there are cell movements, which result in the reorganization of the embryo from blastula to gastrula.
Neurulation is the process of folding in the embryos of vertebrates, where there is the transformation of neural plate into the neural tube. This process induces the formation of the central nervous system.
Invagination is the infolding of one part within another part and it involves the morphogenetic processes by which an embryo takes form and is the initial step of gastrulation.
Thus, the correct answer is the option (C), 'Neurulation'.

Multiple choice

What is the most important part of an egg called?

  1. Shell membrane

  2. Yolk

  3. White

  4. Germ
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In biological terms, the 'germ' or germinal disc is the part of the egg that contains the genetic material and develops into the embryo, making it the most critical part for reproduction.

Multiple choice zoology biotechnology and its applications stem cell stem cells and applications stem cells organ donation and body donation blood and organ donation

The stem cells required for embryonic stem cell culture is obtained from the

  1. Blastocyst.

  2. Liver.

  3. Umbilical cord.

  4. None of the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The inner cells present in the blastocyst are the embryonic stem cells. When the embryonic culture is performed for obtaining the stem cells, the embryo is cultured till the blastocyst stage. The cells present as the inner cell mass are removed which act as a source of pluripotent stem cells which can differentiate into cells of the complete body.

Thus, the correct answer is option A. 

Multiple choice zoology biotechnology and its applications stem cell stem cells and applications stem cells organ donation and body donation blood and organ donation

Identify the wrong statement with respect to embryonic stem cells.

  1. They are pluripotent.

  2. They are isolated from epiblast tissue of blastocyst.

  3. They cannot proliferate in culture medium.

  4. They can give rise to the three germination layers.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Embryonic stem cells are derived from embryos. In human beings, they are derived from inner cell mass of 3 to 5 days old hollow microscopic ball of cells called blastocyst.

Blastocyst is isolated and transferred into a culture dish that contain a nutrient broth. In few days, cells of inner cell mass proliferate and begin spread over the surface of dish.
These proliferated stem cells are pleuripotent and referred to as embryonic stem line.
So, the correct answer is 'They cannot proliferate in culture medium'

Multiple choice biology plant growth growth rates and conditions for growth population ecology growth and development

Prenatal growth in higher vertebrate is 

  1. Auxetic

  2. Accretionary

  3. Multipilicative

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

During pre-natal growth, there is an increase in the number of cells of the organism. So, this kind of growth is referred to as multiplicative or embryonic growth.
Hence, the correct answer is option (C), 'Multiplicative'.

Multiple choice zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

In humans the shape of fully formed placenta is

  1. Cuboidal

  2. Columnar

  3. Pyramidal

  4. Discoidal
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The human placenta is both metadiscoidal and monodiscoidal. Discoidal refers to the structure of the placenta and mono meaning there is only one disc. Metadiscoidal refers to the way the developing placenta becomes discoidal- the villi are scattered at first and then restricted to one disc, that means the placenta becomes mono-discoidal.

So, the correct answer is 'Discoidal'.

Multiple choice zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

Placenta in human beings is formed by

  1. Amnion

  2. Chorion

  3. Allantois

  4. Allantois, chorion and uterine wall
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The placenta is an organ, that connects the developing foetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply, fight against internal infection and produce hormones to support pregnancy. In humans, the placenta usually has a disc shape and it is formed by allantois, chorion and uterine wall.

Multiple choice zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

Mammalian egg contains negligible yolk so the survival of such embryo is made possible by the fact that they are

  1. Nourished through placenta

  2. Too small and need no much food

  3. MiIkfed

  4. None of the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
All mammals except the monotremes are viviparous. In viviparous animals (such as humans ) the eggs have hardly any food reserve. In these animals, embryo receives nutrients from the mother through a special structure called placenta and remains enclosed in the womb (uterus) until birth. This kind of situation is found in higher mammals (eutherians) and some fishes (sharks). In contrast, eggs of oviparous and ovoviviparous animals contain yolk which is utilized by the developing embryo. The yolk contains all the required nutrients. This kind of situation is found in fishes, amphibians, reptiles, birds and primitive mammals.