Difference Between Gametogenesis And Embryogenesis

What Is Gametogenesis?

Gametogenesis is the development of gametes (sex cells) within the gonads—the ovaries and testes. It is a significant part of sexual reproduction, ensuring genetic material variability and perpetuation of the species.

Types of Gametogenesis

The two types of Gametogenesis are:

Spermatogenesis

• It means the production of sperm cells within the testes.

• It implies the division and differentiation of spermatogonia to form mature spermatozoa.

Oogenesis

• The process of formation of egg cells in ovaries.

• It is the development of oogonia to one ovum per cycle of menstruation.

What Is Embryogenesis?

It is the process of development of a fertilized egg, called the zygote, into a fully formed embryo. Embryogenesis is a process quintessential to the formative development of a new organism and consists of successive phases of cell division, differentiation, and morphogenesis.

Stages Of Embryogenesis

• Fertilization: The sperm and egg combine to produce a single zygote.

• Cleavage: Rapid mitotic divisions of a zygote without growth give rise to a multicellular structure called a blastula.

• Blastulation: The process of the formation of the blastula, a hollow ball of cells.

• Gastrulation: Rearrangement of cells in the blastula to form three germ layers: the ectoderm, mesoderm, and endoderm.

• Organogenesis: Development of organs and tissues from the germ layers.

Gametogenesis vs Embryogenesis (Comparison Table)

The difference between gametogenesis and embryogenesis is:

Factors Influencing Gametogenesis And Embryogenesis

The shared factors which influence gamete-genesis and embryogenesis include the following:

Genetic Factors

• The inherited genetic conditions can influence the process of gamete-genesis and embryogenesis.

• Mutations can cause disorders either in gamete production or embryonic development.

Hormonal Regulation

• Gametogenesis is mainly controlled by hormones such as FSH and LH.

• Maternal hormones and growth factors control embryogenesis.

Environmental Factors

• Toxin/radiation exposure adversely affects both processes.

• Nutritional status and maternal health are essential for embryogenesis to take place successfully.

Disorders Related to Gametogenesis

The disorders related to gametogenesis are:

Infertility

Inability to produce any viable sperm or eggs.

Polycystic Ovary Syndrome (PCOS)

Hormonal disorder causing problems in oogenesis.

Disorders Related to Embryogenesis

Some of the disorders related to embryogenesis are:

Congenital Anomaly

It is a structural or functional abnormality present at birth.

Miscarriage

This refers to the expulsion of the embryo or foetus before it becomes viable outside the uterus.

Gametogenesis vs Embryogenesis NEET MCQs (With Answers & Explanations)

Important topics for NEET are:

• Types of Gametogenesis

• Stages of Embryogenesis

Practice Questions for NEET

Q1. Meiocytes are also known as

1) Gamete sister cell

2) Gamete

3) Gamete mother cell

4) Gametophyte

Correct answer: 3) Gamete Mother Cell

Explanation:

In diploid organisms, specialised cells called meiocytes (gamete mother cells) undergo meiosis. At the end of meiosis, only one set of chromosomes gets incorporated into each gamete. At the end of meiosis, only one set of chromosomes gets incorporated into each gamete, ensuring genetic diversity. These haploid gametes, when fused during fertilization, restore the diploid chromosome number, leading to the formation of a new organism.

Hence, the correct answer is option 3) Gamete mother cell.

Q2. Those organisms having both male and female sex organs are

1) Heterothallic

2) Homothallic

3) Monoecious

4) Both b and c

Correct answer: 4) Both b and c

Explanation:

Homothallic or monoecious plants have both the male and the female reproductive parts on the same plant, therefore allowing the making of both sorts of gametes. This makes self-fertilization possible increases reproductive productivity and ensures that the species can survive. These are the varieties of corn and cucumbers, the male flowers produce pollens, and the female produce ovules. Such plants can therefore survive in a wide range of environments by maximizing their reproductive potential.

Hence the correct answer is option 4) Both (b) and (c).

Q3. In majority of sexually reproducing organisms the gametes produced are of two morphologically distinct types. Choose those organisms in the given options

1) Fucus

2) Homo sapiens

3) Cladophora

4) More than one correct

Correct answer: 4) More than one correct

Explanation:

Heterogametes -

In a majority of sexually reproducing organisms, the gametes produced are of two morphologically distinct types (heterogametes).

In such organisms, the male gamete is called the antherozoid or sperm and the female gamete is called the egg or ovum. E.g. Heterogametes of Fucus (an alga) and Heterogametes of Homo Sapiens (human beings).

Hence, the correct answer is option 4) more than one correct answers.

Also Read:

• MCQs on Gametogenesis

• Factors Affecting Plant Growth

• Dithecous Anther