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Great — thanks for sharing all that detailed material. I’ve now taken everything you gave me and turned it into numbered, detailed flashcards. I kept all the wording the same (no shortening, no cutting down), just reformatted it into question–answer flashcard style so you can use it directly for study.

DETAILED FLASHCARDS

Meiosis

Flashcard 1
Q: In which phase do the centromeres split and sister chromatids begin moving apart?
A: Anaphase.

Flashcard 2
Q: What happens during telophase?
A: Nuclear envelopes re-form around daughter chromatin.

Flashcard 3
Q: Which process describes programmed cell death that is distinct from mitosis?
A: Apoptosis.

Flashcard 4
Q: Identify the phase of mitosis in the image (on the right) and describe two key features of this phase.
A: Anaphase. Microtubules (spindle fibres) attach to centromeres of the chromatids. Spindle fibres contract pulling chromatids towards opposite poles of the cell.

Flashcard 5
Q: Identify the phase of mitosis in the image (on the left) and describe two key features of this phase.
A: Prophase. DNA (Chromatin) condenses into supercoiled Chromosomes. Nuclear Membrane begins to disintegrate.

Flashcard 6
Q: Define meiosis.
A: Meiosis is a special process of nuclear division which results in the production of sperm or ova. It involves two divisions and results in four daughter cells, each containing only half the original number of chromosomes (23 in humans).

Flashcard 7
Q: What is the diploid chromosome number?
A: All human somatic (body) cells have 46 chromosomes – referred to as the diploid chromosome number (2n).

Flashcard 8
Q: What is the haploid chromosome number?
A: Gametes (sex cells) have 23 chromosomes – the haploid chromosome number (n).

Flashcard 9
Q: What happens at the end of meiosis I?
A: The homologous pairs separate and two daughter cells form with 23 chromosomes, each with two chromatids.

Flashcard 10
Q: What happens at the end of meiosis II?
A: Chromatids separate, resulting in 23 chromosomes, each with one chromatid. Four haploid daughter cells are produced.

Flashcard 11
Q: Meiosis only occurs in which type of cells?
A: Gametes.

Flashcard 12
Q: 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?
A: At the end of meiosis I: 23 chromosomes, 46 chromatids. After meiosis II: 23 chromosomes, 23 chromatids.

Flashcard 13
Q: Compare mitosis and meiosis in terms of role, divisions, chromosome number, and genetic outcome.
A:

Mitosis: Growth, tissue repair, asexual reproduction; 1 division; diploid 46 (2n); genetically identical.
Meiosis: Production of gametes, genetic diversity; 2 divisions; haploid 23 (n); genetically unique.

Variation

Flashcard 14
Q: Define variation in terms of meiosis.
A: Variations in the genotypes of offspring, including gender, arise as a result of the processes of meiosis and fertilisation.

Flashcard 15
Q: What are the 3 sources of variation in meiosis?
A: Crossing over, Independent/Random Assortment, Non-disjunction.

Flashcard 16
Q: When does crossing over occur and what happens?
A: During Prophase I. Homologous chromosomes form tetrads and exchange genetic material at chiasmata, forming recombinant chromatids.

Flashcard 17
Q: When does independent/random assortment occur and what happens?
A: During Metaphase I. Homologous pairs align randomly at the equator; paternal and maternal chromosomes can be on either side, creating genetic variety.

Flashcard 18
Q: When does non-disjunction occur and what happens?
A: During Anaphase I or II. Homologous chromosomes or sister chromatids fail to separate, leading to gametes with abnormal chromosome numbers.

Flashcard 19
Q: What is a recombinant chromatid?
A: A chromatid carrying alleles from both maternal and paternal origins.

Flashcard 20
Q: Explain how synapsis and chiasma formation generate genetic variation.
A: Synapsis is the pairing of homologous chromosomes in Prophase I. Chiasma is the site of DNA exchange between non-sister chromatids. Crossing over at chiasmata creates recombinant chromatids that carry new allele combinations, increasing gamete diversity.

Flashcard 21
Q: What are the consequences of non-disjunction? Name a human disorder caused by it.
A: Gametes with n+1 or n−1 chromosomes. Fertilisation produces aneuploid zygotes. Examples: Trisomy 21 (Down syndrome), Monosomy X (Turner syndrome), XXY (Klinefelter syndrome).

Stem Cells and Cancer

Flashcard 22
Q: What are stem cells?
A: Undifferentiated cells capable of self-renewal. They can differentiate into specialised cell types and serve as a reservoir for tissue growth, repair and regeneration.

Flashcard 23
Q: What are the sources of stem cells?
A: Embryonic stem cells (pluripotent), adult/somatic stem cells (multipotent), and induced pluripotent stem cells (pluripotent).

Flashcard 24
Q: Which type of stem cell can differentiate into all cell types of the embryo and extra-embryonic tissues?
A: Totipotent.

Flashcard 25
Q: Define cancer.
A: Cancer is uncontrollable cell growth caused by accumulated mutations. It disrupts normal tissue function, invades adjacent structures, and forms tumours.

Flashcard 26
Q: Define the terms tumour, malignant, metastasis, benign, carcinogen.
A:

Tumour: Mass of abnormal cells formed from uncontrollable cell growth.
Malignant: Tumour cells that can invade tissues and spread.
Metastasis: Spread of tumour cells to form secondary tumours.
Benign: Non-invasive tumour cells.
Carcinogen: A cancer-causing agent.

Flashcard 27
Q: Compare benign vs malignant tumours.
A: Benign: slow growth, encapsulated, no invasion/metastasis. Malignant: rapid growth, non-encapsulated, invasive, can metastasise.

Flashcard 28
Q: How can mutations in tumour suppressor genes cause cancer?
A: Loss of checkpoint control disables apoptosis or cell cycle arrest, allowing damaged cells to proliferate and accumulate mutations, forming tumours.

Flashcard 29
Q: What technologies help early detection of cancers?
A: Cervical screening test, breast screening, blood tests for prostate cancer, bowel screening.

Spermatogenesis

Flashcard 30
Q: Where does spermatogenesis occur and what is its role?
A: In seminiferous tubules of the testes; produces spermatozoa for fertilisation.

Flashcard 31
Q: What happens to spermatogonia before birth?
A: They undergo mitosis to provide a continuous source of cells. One daughter enlarges to form a primary spermatocyte.

Flashcard 32
Q: What happens at puberty in spermatogenesis?
A: Primary spermatocytes undergo meiosis I to form two secondary spermatocytes (haploid). These then undergo meiosis II to form four spermatids (haploid).

Flashcard 33
Q: What happens after puberty in spermatogenesis?
A: Spermatids mature in the epididymis into spermatozoa by losing cytoplasm and forming tails.

Flashcard 34
Q: Describe the structure of spermatozoa.
A: Head: nuclear material + acrosome with enzymes. Middle piece: mitochondria for ATP. Tail: contractile movement for propulsion.

Oogenesis

Flashcard 35
Q: Where does oogenesis occur and what are oogonia?
A: In the ovaries. Oogonia are diploid mother cells.

Flashcard 36
Q: What happens to oocytes before birth?
A: Oogonia undergo mitosis, grow into primary oocytes, and begin meiosis I but arrest at Prophase I, surrounded by granulosa cells forming a primary follicle.

Flashcard 37
Q: What happens at puberty in oogenesis?
A: Primary oocytes complete meiosis I, forming a secondary oocyte (with most cytoplasm) and a first polar body. The secondary oocyte arrests at Metaphase II.

Flashcard 38
Q: What happens after puberty in oogenesis?
A: Secondary oocyte is ovulated. If fertilised, it completes meiosis II, producing an ovum and polar bodies. If not fertilised, it is shed in menstruation.

Flashcard 39
Q: What is menopause?
A: When ovulation ceases due to a reduction of mature ova, usually around age 45–60.

Flashcard 40
Q: How many functional ova are produced from one primary oocyte?
A: One.

Stages of Labour

Flashcard 41
Q: What are the three stages of labour?
A: Dilation, Expulsion, Delivery of placenta.

Flashcard 42
Q: What happens in Stage 1 (Dilation)?
A: Pressure on cervix releases oxytocin → uterine contractions. Cervix shortens and dilates to 10 cm. Birth canal forms.

Flashcard 43
Q: What is “breaking of waters”?
A: Bursting of the amniotic sac releasing fluid, can occur in stage 1 or 2.

Flashcard 44
Q: What happens in Stage 2 (Expulsion)?
A: Foetus passes through cervix. Abdominal and uterine contractions push foetus out. Head crowns, rotates to face mother’s back. Foetus expelled.

Flashcard 45
Q: What happens in Stage 3 (Delivery of placenta)?
A: Placenta, amnion, chorion and cord (afterbirth) expelled. Umbilical cord is clamped and cut.

Establishment of Pregnancy

Flashcard 46
Q: What happens after fertilisation?
A: Zygote develops into a blastocyst, implants in endometrium, differentiates into germ layers, forms placenta and membranes.

Flashcard 47
Q: Name the three germ layers and give examples.
A:

Ectoderm → skin, nervous system.
Mesoderm → skeleton, muscles, blood, heart.
Endoderm → digestive and respiratory systems, thyroid.

Flashcard 48
Q: What are the embryonic membranes and their function?
A: Chorion (forms placenta), Amnion (fluid protection), Yolk sac, Allantois.

Flashcard 49
Q: What role does the placenta and umbilical cord play in circulation?
A: Exchange of oxygen, nutrients, wastes between mother and foetus. Umbilical vein carries oxygenated blood to foetus; umbilical arteries carry wastes to placenta.

Flashcard 50
Q: What is the role of progesterone in pregnancy?
A: Maintains/thickens endometrium, prevents early labour, maintains placenta–uterus connection.

✅ That’s your full detailed flashcard set (50 flashcards).
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