B 14 Genetics And Evolution Flashcards Preview

GCSE Biology > B 14 Genetics And Evolution > Flashcards

Flashcards in B 14 Genetics And Evolution Deck (21)
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1
Q

What is a Fossil

A

Fossils are the remains of organisms from millions of years ago that can be found in rocks, ice and other places.

2
Q

How are fossils formed

A

Fossils are formed as a result of absence of decay, hard parts being replaced by minerals as they decay and preserved traces of organisms.

3
Q

Incomplete fossil record

A

Many early organisms were soft bodied (left little fossil trace) also geological processes.

A lot did not become fossilised

Not been found

4
Q

Statements for fossilisation

A

An organism dies.

It get buried under rock or in mud.

This prevents exposure to oxygen.

The organism does not decay.

Minerals replace the hard parts of the organism

This process creates a fossil

5
Q

Using the fossil record

A

Some fossil records are complete like the horse. This can show us how the organism has changed and developed over time. They can reconstruct ecology.

Fossils also show how animals have not changed much over time (sharks)

6
Q

How may extinction occur

A

New predators, new deseases or new, more successful competitors

7
Q

Extinction

A

Is the permanent loss of all the members of a species

8
Q

What happens when conditions change

A

When conditions change, organisms that are better suited to survive the new conditions evolve. However older species that cannot cope with the changes gradually die out as they are not able to compete for food very well and other resources.

9
Q

Natural selection

A

When there is variation exists between populations of organisms, the ones better suited to the environment are able to survive and reproduce, thus passing down their trates.

10
Q

Extinction on a large scale

A

Evidence suggests this could happen as a result of a catastrophic event. (Volcanic eruption)

11
Q

What destroyed the dinosaurs

A

65 million years ago. Giant astroid collided with the earth.

12
Q

How to prevent resistant strains of bacteria

A

Do not overuse antibiotics

Patients need to finish their course of medicine every time (make sure all the bacteria is killed)

13
Q

Classification

A

Is the organisation of living things into groups according to their similarities.

14
Q

Human being scientific names

A

Homo sapiens

15
Q

Domestic cat

A

Felis domesticus

16
Q

Blackthorn

A

Prunus spinosa

17
Q

Malarial parasite

A

Plasmodium falciparum

18
Q

Archaea

A

Primitive forms of bacteria that include extremophiles

19
Q

Bacteria

A

These are the true bacteria (eubacteria) and the cyanobacteria

20
Q

Eukaryota

A

These organisms all have cells that contain a nucleus enclosing genetic material.

21
Q

Evolutionary trees

A

These show how organisms may be related.