Cells And Control

Question 1

What is the cell cycle?

Answer 1

A series of steps that the cell has to undergo in order to divide

Question 2

What does mitosis produce?

Answer 2

2 genetically identical diploid daughter cells, each with identical sets of chromosomes to the parent cell

Question 3

What is cell division by mitosis important for?

Answer 3

Growth and development

Question 4

Why is mitosis a vital part of asexual reproduction?

Answer 4

Type of reproduction that only involves one organism, so to produce offspring it simply replicates its own cells

Question 5

What are the 5 stages of mitosis?

Answer 5

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase
5. Cytokinesis

Question 6

What is interphase?

Answer 6

The longest stage of the cell cycle that involves cell growth

Question 7

What is a chromosome?

Answer 7

A linear DNA molecule tightly coiled around proteins

Question 8

Outline prophase

Answer 8

-DNA condenses, chromosomes become visible
-nuclear membrane disappears

Question 9

Outline metaphase

Answer 9

Chromosomes line up along the cell equator

Question 10

Outline anaphase

Answer 10

-spindle fibres attach to each chromosome

Question 11

Outline telophase.

Answer 11

-Nucleus of the cell divides
-New membrane forms around each set if chromosomes

Question 12

What does cytokines involve?

Answer 12

-division of the cell membrane and cytoplasm
-two genetically identical ‘daughter’ cells produced

Question 13

What is cancer?

Answer 13

-non-communicable
-uncontrolled cell division results in the formation of a primary tumour

Question 14

What are stem cells?

Answer 14

Unspecialised cells that can differentiate into a range of different cell types

Question 15

What does differentiation mean?

Answer 15

The process by which stem cells become specialised ( have a specific function)

Question 16

Why is cell differentiation important?

Answer 16

Enables the formation of specialised tissue with specific functions

Question 17

What are adult stem cells?

Answer 17

Stem cells that can differentiate into a limited range of cell types

Question 18

Where are stem cells found in plants?

Answer 18

Meristems

Question 19

Where is meristem tissue found?

Answer 19

In regions of the plant when cells are continuously dividing

Question 20

What are the benefits of using stem cells in medicine?

Answer 20

• treat damage or disease
• used in scientific research
• growing organs for transplants

Question 21

What is the central nervous system?

Answer 21

Brain and spinal cord

Question 22

What is the function of the spinal cord?

Answer 22

Connects the peripheral nervous system to the brain

Question 23

Whats is the function of the nervous system?

Answer 23

Allows an organism to rapidly react to environmental and internal changes

Question 24

What are neurones?

Answer 24

Nerve cells adapted to quickly transmit nerve impulses

Question 25

What’s the function of a sensory neurone?

Answer 25

Carries impulses from receptors to the CNS

Question 26

What’s the function of a motor neurone?

Answer 26

Carries impulses from the central nervous system to effectors

Question 27

What’s the function of a relay neurone?

Answer 27

Carries impulses from sensory neurones to motor neurones within the CNS

Question 28

How does the CNS coordinates a response to a stimulus?

Answer 28

Stimulus -> sensory receptor detects stimulus-> sensory receptor sends impulses along the sensory neurons to CNS -> CNS coordinates response -> CNS sends information to effector along motor neuron -> effector produces a response to the stimulus

Question 29

What’s a synapse?

Answer 29

Small gap between neurones which a nerve impulse is transmitted via neurotransmitters

Question 30

What’s the reflex arc?

Answer 30

Stimulus -> sensory receptor-> sensory neurone -> relay neurone -> motor neurone -> effector -> response

Question 31

What’s the function of the cornea?

Answer 31

Refracts light entering the eye

Question 32

What’s the structure and function of the iris?

Answer 32

- pigmented ring of circular & radial muscles - controls the side of ou ou, to alter how much light enters the eye

Question 33

What’s the pupil?

Answer 33

Hole in the iris centre that allows light rays to enter the eye

Question 34

What’s the function of the retina?

Answer 34

Convers light energy into neural signals which are sent to the brain via the optic nerve

Question 35

What’s the function of the optic nerve?

Answer 35

It transmits nerve impulses to the brain from the retina

Question 36

Why is the iris reflex important?

Answer 36

Prevents bright light from damaging the retina