L2

Question 1

Characteristics of life (8)

Answer 1

Cellular organisation

Reproduction

Metabolism

Heredity

Response to stimuli

Growth and development

Adaptation through evolution

Question 2

Eukaryote cell size

Answer 2

range 10 - 100 µm

Question 3

Prokaryote cell size

Answer 3

Less than 5 µm

Question 4

Organelle size

Answer 4

Mitochondria 1 - 10 µm

Chloroplasts 2 - 5 µm

Question 5

Bacterium size

Answer 5

1 x 2 µm

Question 6

Animal cell size

Answer 6

20 µm

Question 7

Ribosome size

Answer 7

25 - 30 nm (nanometre)

Question 8

Microfilament size

Answer 8

7 nm (nanometre)

Question 9

Membrane size

Answer 9

7 - 8 nm

Question 10

DNA helix size

Answer 10

2 nm

Question 11

Microtubule size

Answer 11

25 nm

Question 12

Requirements for natural selection

Answer 12

Variation - Individuals in a population vary from one another

Inheritance - Parents pass on their traits to their offspring genetically

Seleection - Some variants reproduce more than others

Time - Successful variations accumulate over many generations

Question 13

Endosymbiosys

Answer 13

The endosymbiosys theory states that two key organelles in eukaryotes are derived from bacteria

MItochondria are derived from proteobacteria, and chloroplasts from cyanobacteria

Question 14

3 Domains of life

Answer 14

Bacteria

Archaea

Eukarya

Question 15

Phylogenetic tree

Answer 15

By identifying shared characters, a family tree of organisms can be created tonsee how closely organisms are related.

There are 3 main groups of domains