Topic 2 - Cells and Control

Question 1

In human cells, what is a chromosome?

Answer 1

a structure found in nuclei, containing a DNA molecule

Question 2

What type of cell division forms two identical daughter cells?

Answer 2

mitosis

Question 3

In which stage of the cell cycle are the chromosomes duplicated?

Answer 3

interphase

Question 4

In which stage of the cell cycle, at the end of mitosis, does the one cell divide into two?

Answer 4

cytokinesis

Question 5

What term describes a cell that has two sets of chromosomes?

Answer 5

diploid

Question 6

Where are plant meristems found?

Answer 6

tips of plant shoots and roots [also just inside bark of trees]

Question 7

What happens in a plant meristem?

Answer 7

Cells divide rapidly by mitosis as the plant grows

unspecialised/stem cells

Question 8

What happens during cell differentiation?

Answer 8

Cells develop special features that help them carry out a particular function.

Question 9

Why is cell differentiation important to plants and animals?

Answer 9

Specialised cells are more effective at carrying out different functions in the body.

Question 10

A root hair cell is a specialised cell. What is its function?

Answer 10

to absorb water and dissolved mineral salts from the soil

Question 11

How is a root hair cell specialised to carry out its function?

Answer 11

It has a long extension into the soil that increases the surface area for absorption

Question 12

Explain how one specialisation of a xylem vessel helps it carry out its function.

Answer 12

any one from: thickened wall to prevent collapse of tube/withstand pressure of water; no cell cytoplasm and lost cell walls to form long tubes through which water flows up the plant; small holes in thick cell wall so water can pass into and out of the vessel from surrounding cells

Question 13

Name one feature, other than mass, that could be measured to show growth in a plant.

Answer 13

any suitable measure that will show change over time, such as: height, tree girth, leaf area, number of leaves

Question 14

Name the type of cell division that cells use to make identical copies of themselves.

Answer 14

mitosis

Question 15

What type of cell has the ability to differentiate into specialised cells?

Answer 15

stem cell

Question 16

In what organ system would you find nerve cells?

Answer 16

the nervous system

Question 17

Are nerve cells diploid or haploid?

Answer 17

diploid

Question 18

What part of a nerve cell contains chromosomes?

Answer 18

nucleus

Question 19

What part of a nerve cell makes proteins?

Answer 19

ribosomes

Question 20

Nerve cells require a lot of energy. What cell structure would you expect them to have a lot of?

Answer 20

mitochondria

Question 21

What is a nerve cell specialised to do?

Answer 21

carry electrical signals/impulses

Question 22

List your senses.

Answer 22

touch, hearing, sight, taste, smell, balance, temperature and plenty of others

Question 23

State the name of one organ in the nervous system.

Answer 23

brain, spinal cord or nerves or a named sense organ

Question 24

What type of cells detect stimuli?

Answer 24

receptor cells

Question 25

In which sense organ would you find receptor cells that detect light waves?

Answer 25

eye

Question 26

What are the electrical signals used in the nervous system called?

Answer 26

impulse

Question 27

List, in order, the organs that an impulse goes through from the hand to the brain.

Answer 27

nerve(s), spinal cord

Question 28

What are the two long ‘arms’ of a sensory neurone called?

Answer 28

dendron and axon

Question 29

List, in order, the parts of a sensory neurone that an impulse goes through.

Answer 29

dendrite, dendron, axon, axon terminal

Question 30

Why are sensory neurones so long?

Answer 30

to carry impulses quickly over long distances

Question 31

What is the name of the fatty sheath that surrounds dendrons and axons?

Answer 31

myelin sheath

Question 32

What does the myelin sheath do?

Answer 32

speeds up transmission of impulses, insulates neurones from each other

Question 33

Where in the eye are receptor cells for light found?

Answer 33

retina

Question 34

What are all the stages in the cell cycle

Answer 34

Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Question 35

What happens in Prophase

Answer 35

The nucleus starts to break down and spindle fibres appear

Question 36

What happens in Metaphase

Answer 36

The chromosomes are lined up on the spindle fibres across the middle of the cell

Question 37

What happens in Anaphase

Answer 37

The chromosome copies are separated and moved to either end of the cell on the spindle fibres

Question 38

What happens in Telophase

Answer 38

A membrane forms around each set of chromosomes to form a nuclei

Question 39

What happens in Cytokinesis

Answer 39

A cell surface membrane forms to separate the two cells. [Cell walls form in plant cells]