Simple Revision

Question 1

What are stem cells?

Answer 1

Unspecialised cells, found in all animals, that have the ability to divide into new stem cells or different types of specialised cell.

Question 2

What are the different types of stem cell? (2)

Answer 2

1. Embryonic stem cells

2. Adult tissue stem cells

Question 3

What are meristems?

And what do they have the potential to become?

Answer 3

Regions of a plant where cell division takes place. Found in tips of roots and shoots.

Any type of plant cell.

Question 4

Briefly describe fertilisation.

Answer 4

Fertilisation takes place when the nucleus of the male gamete ( sperm ) fuses with the nucleus of the female gamete ( egg ) to produce the start of a new individual ( zygote )

Question 5

What is the role of a stigma in a plant?

Answer 5

Traps pollen grains.

Question 6

What are the male and female gametes of a plant? And where are the produced?

Answer 6

Male- pollen produced in the anthers

Female- eggs produced in the ovules

Question 7

What is variation?

Answer 7

The differences between individuals of the same species.

Question 8

Describe continuous variation and give an example.

Answer 8

Can be measured

e.g. Height

Question 9

Describe discrete variation and give an example.

Answer 9

Can’t be measured and is put into groups

e.g. Eye colour

Question 10

What are genes?

Answer 10

Units of inheritance the control characteristics.

Question 11

What are alleles?

Answer 11

Different forms of the same gene.

Question 12

What is a homozygous individual?

Answer 12

Someone that has the same 2 alleles

Question 13

Describe a xylem vessel

Answer 13

Dead, hollow tube that transports water and minerals up the plant to the leaf for photosynthesis.

Question 14

Describe a phloem vessel.

Answer 14

Alive tube that transports dissolved food from the leaf up and down the plant. Controlled by companion cell.

Question 15

What is transpiration?

Answer 15

Evaporation of water through the stomata.

Question 16

What makes up the CNS?

Answer 16

The brain and spinal cord.

Question 17

What does the cerebrum control?

Answer 17

Logic reasoning, conscious thought

Question 18

What does the cerebellum control?

Answer 18

Balance and co-ordination.

Question 19

What does the medulla control?

Answer 19

Breathing and heart rate.

Question 20

What is a synapse?

Answer 20

Gap between neurons that transmits chemicals.

Question 21

What is a reflex action?

Answer 21

An automatic response to a stimulus to protect the body from danger.

Question 22

What are hormones?

Answer 22

Chemical messengers made of protein.

Question 23

What are the job of endocrine glands?

Answer 23

They secrete hormones directly into the blood stream to specific target tissues.

Question 24

What is digestion?

Answer 24

The breakdown of large insoluble food molecules into small soluble good molecules.

Question 25

What is peristalsis?

And why must be present for it to work?

Answer 25

Muscular contractions that push food down the alimentary canal.

Saliva must be present in the digestive tract.

Question 26

What are villi?

Answer 26

Small finger like projection found in the intestine wall where absorption takes place.

Question 27

What do the blood capillaries in the villi absorb?

Answer 27

Glucose & amino acids

Question 28

What does the lacteal in the villi absorb?

Answer 28

Fatty acids and glycerol

Question 29

What is differentiation?

Answer 29

When cells become specialised.