random

Anaphase

In which phase do the centromeres split and sister chromatids begin moving apart?

Telophase

What happens during telophase?

Apoptosis

Which process describes programmed cell death that is distinct from mitosis?

Anaphase

Identify the phase of mitosis in the image (on the right) and describe two key features of this phase.

Prophase

Identify the phase of mitosis in the image (on the left) and describe two key features of this phase.

Meiosis

Define meiosis.

Diploid chromosome number

What is the diploid chromosome number?

Haploid chromosome number

What is the haploid chromosome number?

End of meiosis I

What happens at the end of meiosis I?

End of meiosis II

What happens at the end of meiosis II?

Gametes

Meiosis only occurs in which type of cells?

Diploid human germ cell after meiosis I and II

A diploid human germ cell (2n = 46) enters meiosis. How many chromosomes and chromatids are present at the end of meiosis I and in each gamete after meiosis II?

Mitosis vs Meiosis

Compare mitosis and meiosis in terms of role, divisions, chromosome number, and genetic outcome.

Variation in meiosis

Define variation in terms of meiosis.

Sources of variation

What are the 3 sources of variation in meiosis?

Crossing over

When does crossing over occur and what happens?

Independent/random assortment

When does independent/random assortment occur and what happens?

Non-disjunction

When does non-disjunction occur and what happens?

Recombinant chromatid

What is a recombinant chromatid?

Synapsis and chiasma

Explain how synapsis and chiasma formation generate genetic variation.

Non-disjunction consequences

What are the consequences of non-disjunction? Name a human disorder caused by it.

Stem cells

What are stem cells?

Sources of stem cells

What are the sources of stem cells?

Totipotent

Which type of stem cell can differentiate into all cell types of the embryo and extra-embryonic tissues?

Cancer

Define cancer.

Tumour definitions

Define the terms tumour, malignant, metastasis, benign, carcinogen.

Benign vs malignant tumours

Compare benign vs malignant tumours.

Tumour suppressor genes

How can mutations in tumour suppressor genes cause cancer?

Early detection technologies

What technologies help early detection of cancers?

Spermatogenesis

Where does spermatogenesis occur and what is its role?

Spermatogonia before birth

What happens to spermatogonia before birth?

Puberty in spermatogenesis

What happens at puberty in spermatogenesis?

Spermatogenesis after puberty

What happens after puberty in spermatogenesis?

Structure of spermatozoa

Describe the structure of spermatozoa.

Oogenesis location and origins

Where does oogenesis occur and what are oogonia?

Oocytes before birth

What happens to oocytes before birth?

Puberty in oogenesis

What happens at puberty in oogenesis?

Oogenesis after puberty

What happens after puberty in oogenesis?

Menopause

What is menopause?

Functional ova from primary oocyte

How many functional ova are produced from one primary oocyte?

Stages of labour

What are the three stages of labour?

Stage 1 (Dilation)

What happens in Stage 1 (Dilation)?

Breaking of waters

What is 'breaking of waters'?

Stage 2 (Expulsion)

What happens in Stage 2 (Expulsion)?

Stage 3 (Delivery of placenta)

What happens in Stage 3 (Delivery of placenta)?

After fertilisation

What happens after fertilisation?

Three germ layers

Name the three germ layers and give examples.

Embryonic membranes

What are the embryonic membranes and their function?

Placenta and umbilical cord

What role does the placenta and umbilical cord play in circulation?

Role of progesterone in pregnancy

What is the role of progesterone in pregnancy?