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Question 1

Mitosis

Answer 1

When a cell splits to form two daughter cells that are identical to the parent cell

Question 2

Diploid

Answer 2

Two sets of chromosomes (46)

Question 3

Haploid

Answer 3

One set (23)

Question 4

What happens during interphase

Answer 4

Cell is copying itself and making copies of cell parts
The chromosomes that are copied attach togehter making an x shape

Question 5

What order is mitosis

Answer 5

Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

Question 6

What happens in prophase

Answer 6

The nucleus starts to breakdown and spindle fibres appear
Nucleus has chromosomes in the middle with spindle fibres shown as a line in the membrane

Question 7

What happens in metaphase

Answer 7

The chromosomes lineup on the spindle fibres across the middle of the cell
The chromosomes are in exes on spindle fibres in a straight line across the radius of the cell

Question 8

What happens in anaphase

Answer 8

The chroma zones are separated and move to opposite ends of the cell on the spindle fibres
The exes have been separated on our parallel to each other across the radius

Question 9

What happens in telephase

Answer 9

A membrane forms around each set of chromosomes to form nucleus
The cell is splitting into it looks like an eight with half the chroma zones in the top and a half the chromosomes in the bottom

Question 10

What happens in cytokinesis

Answer 10

The cell surface membrane forms to separate the two cells so we are ended up with two daughter cells that are identical

Question 11

Why do we need mitosis to happen

Answer 11

For growth and repair

Question 12

What does asexual production produce

Answer 12

Offspring that are clones which means that their cells have the same chromosomes as the parent and they are genetically identical to the parent

Question 13

What is an example of asexual reproduction

Answer 13

Strawberry plants reproduce asexually by using runner stems along the ground and this makes use of mitosis

Acids also reproduce asexually

Question 14

what are the advantages of asexual reproduction

Answer 14

It is much faster than sexual reproduction
It doesn’t require finding a mate
It is efficient

Question 15

What are the disadvantages of asexual reproduction

Answer 15

It doesn’t produce variation so if a disease or a changing environment happens they can wipe out a whole species because none of them have different characteristics that might enable them to survive

Question 16

Cancer tumours

Answer 16

Or a result of excessive mitosis and are caused by changes in cells that turn them into cancer cells and they undergo uncontrollable mitosis. This rapid cell division produces lumps called tumours that can damage the body and results in cancer and sometimes death

Question 17

Definition of growth

Answer 17

An increase in size as a result of an increase in number or size of cells
This can be recorded by taking measurements over time like length mass or weight

Question 18

Why is growth not charted in the first two weeks of a babies life in a percentile chart

Answer 18

Because they often lose weight as they are just a feeding from the breast rather than from the placenta

Question 19

What does it mean if the 25th percentile for an eight month old baby is 8 kg

Answer 19

This means that 25% of all eight month old babies have a mass below 8 kg
75% of all eight month old babies have a mass above 8 kg

Question 20

Cell differentiation

Answer 20

Is when less specialised cells are adapted through the process of differentiation to become specialised for other functions.

Question 21

Adaptations of a red blood cell

Answer 21

No nucleus so there’s more space for haemoglobin to be carried
Large surface area allowing oxygen to diffuse in and out more quickly

Question 22

Adaptations of a fat cell

Answer 22

Cytoplasm of fat cells is filled with large fat droplets. The fact is stored until the body needs energy

Question 23

Adaptations of a nerve cells

Answer 23

Nerve cells have a long fiver that carries electrical impulses around the body

Question 24

Muscle cell adaptations

Answer 24

Contain special contractile proteins that can shorten the cell

Question 25

What are meristems

Answer 25

A group of cells near the end of each shoot that allows plants to continue growing. 30 divide rapidly by mitosis. These cells that are produced can then increasing length and differentiate into specialised cells

Question 26

Adaptations of a xylem cell

Answer 26

Thickened water with stand water pressure Tiny pores in wall to allow water and mineral salts to enter and leave No cytoplasm so the vessel is empty for a flow of water to pass through it Loss of cell walls to form a tube

Question 27

Stem cells in plants

Answer 27

They can produce any kind of specialised cells throughout the life of a plant and these are found in the meristems

Question 28

Embryonic stem cells

Answer 28

Can produce any type of specialised cells

Question 29

Adult stem cells

Answer 29

Can only produce the type of specialised cell that is around them

Question 30

How are stem cells used to treat different diseases

Answer 30

They are stimulated to produce the specialised cell that are needed and then injected into the place required. Embryonic stem cells are the best to use for this because they can specialise into any cell, we use bone marrow stem cells in the cases of blood disease.

Question 31

Problems with stem cells

Answer 31

Problems with stem cells include that if they continue to divide inside the body they can cause cancerous tumours There are ethical issues with the way that embryonic stem cells are harvested And stem cells from one person often killed by the immune system of another because it is rejected the stem cells

Question 32

What does the cerebral cortex do

Answer 32

It is used for offenses language memory consciousness and behaviour. It is divided into two cerebral hemispheres that have different functions the right hemisphere communicates with the left side of the body and vice versa

Question 33

Hippo Campus

Answer 33

Located underneath the cerebral hemispheres and is thought to be involved in memory and navigation

Question 34

Cerebellum

Answer 34

The base of the brain is divided into 2 halves Controls balance and posture. Coordinates the timing and fine control of muscle activity making sure movements are smooth musicians have developed a bigger cerebellum because they have fine hand movements when they play their instrument

Question 35

Medulla oblongata

Answer 35

Connects to the spinal cord Controls your heart rate and your breathing right And is responsible for reflexes like vomiting sneezing and swallowing