Cell Division and Reproductive Biology

These flashcards cover key concepts related to cell division, meiosis, and reproductive biology, aiding in the review and understanding of critical processes in cellular biology.

What are the three reasons cells divide?

Growth, repair, and reproduction.

What is apoptosis?

Programmed cell death, a normal cellular process.

What is necrosis?

Premature death of cells caused by factors such as infection, toxins, or trauma.

What are chromosomes made of?

DNA wrapped around proteins called histones.

What is a karyotype?

A picture of all the chromosomes in a cell, arranged in pairs.

What is the purpose of cell division during the G1 phase?

The cell synthesizes proteins necessary for division.

What occurs during the S phase of the cell cycle?

Each chromosome is replicated to produce identical copies.

What is the function of DNA helicase in DNA replication?

It unwinds the DNA, creating a replication fork.

What happens during prophase in mitosis?

Nuclear membrane dissolves and mitotic spindle appears.

What is the significance of the G1/S checkpoint?

It assesses DNA damage and nutrient availability.

What distinguishes meiosis from mitosis?

Meiosis generates gametes, while mitosis is for somatic cell division.

What occurs during crossing over in meiosis?

Non-sister chromatids exchange genetic material, resulting in genetic variation.

What is the main outcome of oogenesis?

It produces one functional ovum and three polar bodies from each primary oocyte.

How does maternal age affect fertilization and pregnancy?

Increased risks of failed fertilization, miscarriage, and genetic disorders such as Down syndrome.

What is oocyte cryopreservation?

A procedure to freeze eggs, allowing women to preserve egg quality.

What occurs during cytokinesis?

The cell begins to divide after mitosis or meiosis.

What type of cells undergo meiosis?

Germ cells, which produce gametes.

How many rounds of DNA replication occur in meiosis?

One round.

What type of cells are diploid?

Cells that contain two sets of chromosomes, one from each parent.

What is a primary characteristic of haploid cells?

They contain a single set of chromosomes, half the number found in diploid cells.

What role do sex chromosomes play in a karyotype?

They are the 23rd pair of chromosomes, determining the sex of the individual.