Cell Division, Cell Diversity & Cellular Organisation

Question 1

What are the phases of interphase?

Answer 1

G1, S, G2.

Question 2

What happens during G1 phase?

Answer 2

Cell grows. Organelles and proteins made.

Question 3

What happens during S phase?

Answer 3

DNA replication.

Question 4

What happens during G2 phase?

Answer 4

Cell checks DNA and prepares for division

Question 5

What happens during mitosis?

Answer 5

Nucleus divides to form two genetically identical nuclei

Question 6

What happens during cytokinesis?

Answer 6

Cytoplasm divides to form two cells

Question 7

How is the cell cycle regulated?

Answer 7

Controlled by chemical signals and checkpoints

Question 8

What is the role of checkpoints in the cell cycle?

Answer 8

Ensure accurate DNA replication and division.

Question 9

What happens during prophase?

Answer 9

Chromosomes condense. Nuclear envelope breaks down. Spindle forms.

Question 10

What happens during metaphase?

Answer 10

Chromosomes align at equator.

Question 11

What happens during anaphase?

Answer 11

Sister chromatids pulled to opposite poles.

Question 12

What happens during telophase?

Answer 12

Nuclear envelope reforms. Chromosomes decondense.

Question 13

What is the significance of mitosis?

Answer 13

Growth, repair, asexual reproduction.

Question 14

What is the significance of meiosis?

Answer 14

Produces haploid gametes. Increases genetic variation.

Question 15

What is independent assortment?

Answer 15

Random arrangement of homologous chromosomes.

Question 16

What is crossing over?

Answer 16

Exchange of DNA between homologous chromosomes

Question 17

What is a homologous chromosome?

Answer 17

Pair of chromosomes, one from each parent, same genes.

Question 18

What are the stages of meiosis?

Answer 18

Interphase, prophase I, metaphase I, anaphase I, telophase I, prophase II,
metaphase II, anaphase II, telophase II.

Question 19

What are the stages of meiosis?

Answer 19

Biconcave, no nucleus, haemoglobin.

Question 20

How are neutrophils specialised?

Answer 20

Multilobed nucleus, lysosomes.

Question 21

How are squamous epithelial cells specialised?

Answer 21

Flat for diffusion. One cell thick.

Question 22

How are ciliated epithelial cells specialised?

Answer 22

Cilia move mucus. Found in airways.

Question 23

How are sperm cells specialised?

Answer 23

Tail for movement. Acrosome contains enzymes.

Question 24

How are palisade cells specialised?

Answer 24

Many chloroplasts. Thin walls. Tightly packed.

Question 25

How are root hair cells specialised?

Answer 25

Large surface area. Thin cell wall. Many mitochondria

Question 26

How are guard cells specialised?

Answer 26

Can change shape. Control stomatal opening.

Question 27

What is a tissue?

Answer 27

Group of similar cells working together

Question 28

What is an organ?

Answer 28

Group of tissues working together

Question 29

What is an organ system?

Answer 29

Group of organs working together

Question 30

Give examples of animal tissues

Answer 30

Squamous epithelium, ciliated epithelium, muscle, cartilage.

Question 31

Give examples of plant tissues.

Answer 31

Xylem, phloem.

Question 32

What is a stem cell?

Answer 32

Undifferentiated cells that can divide and specialise.

Question 33

What are erythrocytes and neutrophils derived from?

Answer 33

Stem cells in bone marrow.

Question 34

What are xylem and phloem derived from?

Answer 34

Stem cells in plant meristems

Question 35

What are the uses of stem cells in medicine and research?

Answer 35

Repair tissues. Treat neurological conditions. Research in developmental biology