Biology

Embryonic Development

572 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

Periderm is made up of

  1. phelloderm

  2. phellogen

  3. phellem

  4. All of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Periderm is composed of cork (phellem), the cork cambium (phellogen), and the phelloderm.

Multiple choice

The process of attaching the embryo with the uterus is known as

  1. gestation

  2. menstruation

  3. implantation

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

Implantation may be defined as the attachment of the fertilized egg to the uterine wall or in other words attaching the embryo with the uterus .It typically happens seven to ten days after ovulation, but it can happen a few days earlier or later as well.

Multiple choice

The normal or Polygonum type of embryo sac is

  1. bisporic eight-nucleate

  2. monosporic four-nucleate

  3. tetrasporic sixteen-nucleate

  4. monosporic eight-nucleate
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Polygonum type of embryo sac is the most common type in angiosperms. It is monosporic, meaning it develops from a single megaspore, and it contains eight nuclei.

Multiple choice

Tegmen develops from

  1. outer integument

  2. inner integument

  3. chalaza

  4. funicle
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In an ovule, the seed coat consists of two layers: the outer testa (from the outer integument) and the inner tegmen (from the inner integument).

Multiple choice

The mesenchyme developing just below the germinal epithelium is the origin of which analogous cell types?

  1. Leydig and thecal cells

  2. Spermatogonia and oogonia

  3. Sertoli and granulosa cells

  4. Sex cords

  5. Ovarian tissue
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mesenchyme arising beneath the germinal epithelium in the testes is the precursor to testicular interstitial cells or Leydig cells. In the ovaries it is the precursor to ovarian stroma or thecal cells.

Multiple choice

Divisions in frog's egg is

  1. holoblastic

  2. meroblastic

  3. diploblastic

  4. triploblastic
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Frog eggs are mesolecithal, meaning they have a moderate amount of yolk. The cleavage is holoblastic, meaning the entire egg divides, though it is unequal.

Multiple choice

Which one of the following sets of organs is derived from ectoderm?

  1. Brain, spinal cord, pituitary, thyroid

  2. Brain, spinal cord, liver, pancreas

  3. Brain, spinal cord, pituitary, pineal

  4. Heart, eye, dentine, skeleton
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The brain, spinal cord, pituitary gland, and pineal gland are all derived from the ectoderm during embryonic development.