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Flashcards in Key Concepts Deck (41):
1

Eukaryotic cell

Has a nucleus

2

Prokaryotic cell

Has no nucleus

3

Sub cellular structures in animal cell

Nucleus
Cell membrane
Mitochondria
Ribosomes

4

Sub cellular structures in plant cells

Nucleus
Cell membrane
Cell wall
Chloroplasts
Mitochondria
Vacuole
Ribosomes

5

Sub cellular structures in bacteria cell

Chromosomal DNA
Plasmid DNA
Cell membrane
Ribosomes
Flagella

6

Specialised cells examples

Sperm
Egg
Ciliates epithelial

7

How is sperm adapted

Acrosome
Haploid nucleus
Mitochondria
Tail

8

How is egg adapted

Nutrients in cytoplasm
Haploid nucleus
Changes in cell membrane after fertilisation

9

Light microscope

Uses light and it’s greatest possible magnification is around x2000

10

Electron microscopes

Uses electrons, can view object up to around x10 million

11

Why is electron microscope better

Can see cell structures and organelles more clearly

12

Pico

(10^-12)

13

Milli

(10^-3)

14

Nano

(10^-9)

15

Micro

(10^-6)

16

What are enzymes

Biological catalysts

17

Enzymes have to be _____ to their substrate

Specific

18

3 factors that affect enzyme activity

Temperature
Substrate concentration
pH

19

Why do enzymes have to be specific

So that the substrate is able to fit into the active site of the enzyme

20

What happens when an enzyme is denatured

The active site changes shape and therefore the substrate cannot fit

21

What happens with enzymes at low temperatures

Molecules move more slowly so the reaction is slower as it takes longer for the substrate to fit into active site

22

What is the optimum temperature

The point at which the enzyme works at its fastest rate

23

What does adding more substrate cause to happen

Increases rate of reaction

24

Why is there a limit to the amount of substrate that speeds the reaction

Eventually the active site of every enzyme will be busy

25

Optimum temperature for enzymes to work at (usually)

37C

26

Why does pH affect enzyme activity

Can change shape of active site

27

What is enzymes sole purpose

Break down large molecules into smaller ones, so they can be in the bloodstream

28

What enzymes digests carbohydrates

Amylase

29

What does amylase do

Digest carbohydrate (eg starch) into sugar (eg glucose)

30

Enzyme that digests lipids

Lipase

31

What does lipase do

Digest lipids (eg energy storage) into fatty acids/glycerol (eg for respiration)

32

What enzyme digests proteins

Protease

33

What does protease do

Digest protein (eg for muscle cells) into amino acids (eg to make enzymes)

34

What does it mean that an enzyme is a catalyst

It speeds up the reaction but is not used

35

What does iodine test for and how

Starch
If present - blue black
If not present - yellow/orange

36

What does Benedicts solution test for and how

Sugar
If present - green>orange>red (depend on how much sugar)
If not present - blue

37

Wha does biuret test test for and how

Protein
If present- pale purple
If not present- pale blue

38

What does ethanol test for and how

Fat
If present- cloudy
If not present - clear

39

What is diffusion

High concentration of molecules moves to a low concentration
Eg gaseous exchange

40

What is active transport

Low concentration of molecules to a high concentration
Eg roots absorb nutrients from soil

41

What is osmosis

Movement of water from high concentration to low