KA1- Producing New Cells

Question 1

What is mitosis

Answer 1

Cell division
Process of a diploid cell dividing

Question 2

What carries out mitosis

Answer 2

Stem cells

Question 3

Why is mitosis important

Answer 3

Provides new cells for growth
Repairs damaged tissues
Repairs damaged or dead cells
Maintains the diploid chromosome complement which is important so no information is lost and the cells can carry out the same function as the parent cell
For growth

Question 4

What controls mitosis

Answer 4

The nucleus

Question 5

What happens in mitosis

Answer 5

2 identical daughter cells are produced which contain the same number of chromosomes as the parent cell

Question 6

Why do cells need to divide

Answer 6

To produce new cells for growth and repair of damaged cells

Question 7

Stage 1 of mitosis

Answer 7

Chromosomes become visible
Each chromosome made up of 2 identical chromatids joined by centrometre

Question 8

Stage 2 of mitosis

Answer 8

Chromosomes line up at equator of cells and attach to spindle fibers by their centrometres

Question 9

Stage 3 of mitosis

Answer 9

Spindle fibers contract
Chromatids pulled apart to opposite side of the cell

Question 10

Stage 4 of mitosis

Answer 10

Nuclear membrane reforms and cytoplasm divided between new cells
Two identical daughter cells, each containing the same number of chromosomes as the original cells are formed

Question 11

What is a chromosome complement

Answer 11

The number of chromosomes a cell contains

Question 12

What is the structure of a chromosome

Answer 12

2 identical chromatids joined by a centrometre

Question 13

Diploid

Answer 13

2 sets of chromosomes

Question 14

What are stem cells in animals

Answer 14

Unspecialised cells

Question 15

What can stem cells in animals do

Answer 15

Divide by mitosis in order to self renew which keeps their population relatively constant
Become different types of cells

Question 16

What are stem cells in animals involved in

Answer 16

Growth and repair

Question 17

What are the two types of stem cells

Answer 17

Embryonic and tissue

Question 18

Where are embryonic stem cells derived from

Answer 18

Embryos that develop from eggs that have been fertilised in a laboratory

Question 19

What are embryonic stem cells capable of

Answer 19

Developing into all cell types

Question 20

Where are tissue stem cells found

Answer 20

Among other differentiated cells in a tissue or organ
Many tissues such as the bone marrow, brain skeletal muscle, blood vessels, skin, liver, teeth and the heart

Question 21

What are tissue stem cells capable of

Answer 21

Becoming cells of that tissue
Regenerating surrounding cells damaged by disease or injury etc

Question 22

What is specialisation of cells

Answer 22

Groups of organs work together to form systems
Hierarchy exists: cells —) tissues —) organs —) systems —) organism
Examples:
Muscle cell —) muscle tissue —) heart —) circulatory system —) the circulatory system makes up part of the human body
Root hair cell —) root tissue —) root —) vascular bundles make up transport system —) transport system makes up part of plant

Question 23

What does the specialisation of cells lead to

Answer 23

The formation of a variety of cells, tissues and organs

Question 24

Specialised animal cell examples

Answer 24

Nerve cell: axon allows transmission of electrical nerve impulses
Red blood cells: carry oxygen to body tissue, contain haemoglobin, no nucleus
Sperm cells: male sex cells, have a tail to swim to egg cell

Question 25

Specialised plant cell examples

Answer 25

Root hour cell: large surface area to allow absorption of water and minerals
Guard cell: control gas exchange charging shape by opening and closing stomata
Palisade cell: chloroplasts present and primary site of photosynthesis in leaf