Variation And Genes

Question 1

Key features of a fish and examples

Answer 1

Scales, lives in water, lays eggs, gills. E.g Gola fish

Question 2

Key features of amphibians and examples

Answer 2

Cold blooded, smooth lives in water and land. E.g frogs

Question 3

Features of reptiles and examples

Answer 3

Scales, lays eggs. E.g crocodile

Question 4

Features of mammals and example

Answer 4

Hair or fur, warm blooded, live birth, lungs. E.g tiger

Question 5

Features of birds and examples

Answer 5

Feathers, warm blooded, lays eggs, lungs

Question 6

Examples of inherited and environmental genes

Answer 6

Inherited - eye colour, hair colour, height, freckles, blood group, shape of nose.

Environmental - sporting skill, scars, hair length, accent

Question 7

The nucleus is…

Answer 7

The centre of a human cell.

Question 8

Inside the nucleus is…

Answer 8

23 pairs of chromosomes

One chromosome form each pair comes from each parent

Question 9

Along the chromosomes are…..

Which are sections that…..

Answer 9

Genes, which are sections that code for specific features

Question 10

There are two versions of each gene, these are called…..

Answer 10

Alleles. These determine what you look like.

If both parents give you an allele for blue eyes, you will have blue eyes.

Question 11

A nucleus contains…

2nd

Answer 11

Most of the cells genetic material

Question 12

In a human cell there are how many chromosomes?

Answer 12

46

Question 13

DNA has what shape

Answer 13

DNA has a double helix shape

Question 14

Dominant and recessive genes

Answer 14

Because, in eye colour, brown eyes are dominant and blue eyes are recessive, if you got a brown allele from one parent and a blue eye allele from another, you would have brown eyes

Question 15

Fossils are…

Answer 15

A fossil is the remains of impression of a prehistoric plant or animal embedded in rock and preserved in a petrified form

Question 16

The three types of fossils are…

Answer 16

1. Impression fossils
2. Preserved organisms
3. Mineral replacement

Question 17

Preserved organisms

Answer 17

Amber is the historic remains of tree resin. Amber sometimes contains animals or plant matter that become caught in the resin as it was secreted

Question 18

What are the best conditions for an animal to be fossilized

Answer 18

1. Hard skeletal bodies
2. Near to water to be covered up or in the desert where the wind will cover it with sand
3. Correct sediment. Either in dry sand or alkaline mud.

Question 19

A species is…

Answer 19

A group of organisms that have characteristics in common and can interbreed to produce fertile offspring

Question 20

What is the process of Natural selection

Beginning with mutation

Answer 20

Mutation
Genetic variation
Better adapted 
Outcompetes others
Survival of the fittest
Breed
Passed on gene

Question 21

Who came up with the theory of evolution

Answer 21

Charles Darwin

Question 22

What is the definition of extinction

Answer 22

When no individuals of a species remain

Question 23

Possible causes of extinction (5)

Answer 23

1. Environment changes quickly
2. A new predator
3. A new disease
4. Competition with a new species for food.
5. A catastrophic event e.g volcano