B1 Topic 1 - Variation

Question 1

What are the characteristics of plants?

Answer 1

They are Autotrophs (they make their own food)
They have chlorophyll
They are multicellular
Have cell walls

Question 2

What are the characteristics of an Animal?

Answer 2

They are heterotrophs ( they have to move about to find things to eat)
They are multicellular
Don’t have cell walls
Don’t have chlorophyll

Question 3

What are the characteristics of Fungi?

Answer 3

They are saprophytes (they feed off dead organisms)
Are multicellular
Have a cell wall
Don’t have chlorophyll

Question 4

What are the characteristics of protoctists?

Answer 4

They are unicellular

They have a nucleus

Question 5

What are the characteristics of prokaryotes?

Answer 5

They are unicellular

They don’t have a nucleus

Question 6

What organism cannot be put into any kingdom?

Answer 6

Viruses because thy are non living

Question 7

List the subdivisions of the kingdoms in order

Answer 7

Kingdom 
Phylum
Class
Order
Family
Genus
Species

Question 8

Animals in the phylum Chordata all have a what?

Answer 8

A supporting rod. The backbone

Question 9

List the groups that’s vertebrates are divided into

Answer 9

Fish
Amphibians
Reptiles
Birds
Mammals

Question 10

Name one vertebrate that doesn’t fit into one class

Answer 10

Duck billed platypus

Question 11

What is the difference between oviparous and viviparous

Answer 11

Oviparous lays eggs whereas viviparous give birth to live young

Question 12

What is genetic variation?

Answer 12

The mixing of genes from two parents

It can also occur due to mutations - changes in the organisms genes.

Question 13

What is environmental variation?

Answer 13

Any difference that’s caused by the environment an organism lives in

Example:

1) a plant grow on a sunny windowsill would grow healthy and green.
2) but the same plant grown in darkness would grow tall and spindly and its leaves would turn yellow

Question 14

Explain continuous variation

Answer 14

It is when the individuals in a population vary within a range
There are no separate groups E.g. Humans can be any height within a range

Question 15

Explain discontinuous variation

Answer 15

It is when there are two or me separate groups

Each individual can only fall into one of these groups E.g. Humans can have a blood group A,B,AB or O

Question 16

Explain how organisms in volcanic vents are adapted to high temperatures

Answer 16

Volcanic vents (hydrothermal vents) in the seabed send out hot water and minerals into the ocean
Bacteria live on chemicals from the vent
The the conditions are extremely hot and under high temperature so the organisms have adapted to cope with this

Question 17

How does natural selection work?

Answer 17

• most organisms give birth to more young that will survive to become adults
• individuals have to compete with each other for resources
• individuals that have characteristics which better match the environment have a better chance of survival and being able to breed.
• these useful characteristics are more likely to be passed on to the next generation
• over time there will be more and more individuals with the better characteristics

Question 18

What is the evidence to support evolution

Answer 18

DNA RESEARCH

1) evolution means all organisms are related
2) scientists found that there is evidence to support this E.g. Humans and chimps have very similar DNA, so are closely related

RESISTANT ORGANISMS

1) the poison warfarin was used to kill rats
2) but a certain gene gives rats resistance to warfarin
3) rats with the resistance have a better change of survival and breeding successfully
4) so now some rat populations are warfarin resistant
5) this is a real life example of natural selection

Question 19

Most cells in your body have a …… Which contains …..

Answer 19

Nucleus

Chromosomes

Question 20

The human cell nucleus contains how many pairs of chromosomes?

Answer 20

23 - there are two number 19 chromosomes, two number 12s, two number 3s etc

Question 21

Chromosomes carry …. Which control …..

Answer 21

They carry genes and different genes control different characteristics e.g. Eye colour

Question 22

There can be different versions of the same gene, called a ….

Answer 22

Allele

Question 23

What is cystic fibrosis and what is it caused by?

Answer 23

It’s a genetic disorder caused by s recessive allele
It results in the body producing thick sticky mucus in the air passages, gut and pancreas
The symptoms include breathing problems, lung infections and fertility problems
People with only one copy of the allele (e.g. Ff) won’t have the disorder, they’re carriers
For a child to have a chance of inheriting the disorder, both parents must be carriers or sufferers (ff)

Question 24

What is sickle cell anaemia

Answer 24

It is a genetic disorder where red blood cells are a funny shape
These blood cells can get stuck in capillaries (tiny blood vessels) so body cells don’t get enough oxygen.
Symptoms include painful joins and muscles, fever and tiredness

Question 25

What are the five kingdoms?

Answer 25

Plants
Fungi
Protoctists
Animals
Prokaryotes