Oogenesis

Question 1

Oogenesis

Answer 1

The production and development/maturation of ovum also known as a mature egg cell

Question 2

Oogonia

Answer 2

There are the stem cells that can divide into the ova.

They under go mitosis in order to replicate.

Before the female is born oogonia replicate until there are about 500,000 of them.

They grow and mature into primary oocytes before the girl is even born.

Question 3

Oocytes

Answer 3

These cells are equivalent to male spermatocytes, they will undergo meiosis. They will produce a single mature ovum/egg cell

Question 4

Primary oocytes.

Answer 4

Type of oocyte that enters into meiosis before the mother is even born and stops during prophase in the first meiotic division.

These primary oocytes will stay suspended in prophase 1 until the female undergo’s puberty.

Each one is surrounded by a layer of follicle cells in the ovary for years.

They will undergo meiosis and produce a secondary spermatocyte and a first polar body.

Question 5

Menstrual cycle

Answer 5

The menstrual cycle is the monthly process where a female’s body prepares for pregnancy

Question 6

Secondary oocytes

Answer 6

The secondary oocytes immediately moves into meiosis 2… but stops again. This time in metaphase.

This occurs at the same time of ovulation.

Most oocytes will never complete meiosis, only the oocytes that have been penetrated by spermatozoa will complete meiosis.

Question 7

Ovulation

Answer 7

release of the secondary oocyte from the ovary, ready for potential fertilisation.

Question 8

Fertilisation

Answer 8

Once the sperm has fused with thee egg, its nucleus is known as the male pronucleus, travels through one cells until it fuses with the female pronucleus.

Once this occurs, the cell is now known as a zygotes.

The remainder of the sperm cell is digested by the ovum.

Question 9

Acrosome

Answer 9

An acrosome is located at the tip of the sperm, it contains enzymes that help to break the connection between the cells of the corona radiata. Allowing the sperm to break through that layer.

Contact with the zona pellucida triggers an acrosome reaction.

Only getting through that layer, the sperm will encounter the cell membrane.

Question 10

Primary Follicle

Answer 10

• Early stage of follicle development in the ovary.
• When primary oocytes begin and stop at the prophase 1. Each of these primary oocytes is surrounded by a single layer of cells, forming a primary follicle.

Question 11

Polar body

Answer 11

A polar body is a small cell that forms during oogenesis, when the primary oocyte or secondary oocyte divides by meiosis.

The polar body helps ensure the division has been done accurately.

Question 12

Ovum

Answer 12

Mature egg cell

Question 13

Zona pellucida

Answer 13

a specialised extracellular matrix that surrounds the oocyte (egg cell).

It’s a thick, transparent layer composed of glycoproteins that plays crucial roles in fertilisation and early embryo development.

Question 14

Corona radiata

Answer 14

a layer of cells that surrounds the egg (oocyte) and the zona pellucida, a glycoprotein matrix.

It’s essentially the outermost layer of cells protecting the developing egg and is composed of granulosa cells.