Key concepts - topic 1 (pg 1-12) paper 1 & 2 Flashcards Preview

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Flashcards in Key concepts - topic 1 (pg 1-12) paper 1 & 2 Deck (34):
1

cell membrane

controls what enters and leaves the cell e.g. oxygen

2

nucleus

large structure that contains genes (DNA) that control the cell

3

cytoplasm

jelly substance that fills the cell - reactions take place here

4

mitochondria

where respiration happens, releasing energy for cell processes

5

ribosomes

(in the cytoplasm, not visible at this size) where proteins are made (protein synthesis)

6

chloroplasts

PLANT ONLY - where photosynthesis takes place making food for the cell

7

cell wall

PLANT ONLY - made of cellulose, tough, supports and keeps the cells shape

8

vacuole

PLANT ONLY - contains cell sap, keeps the cell rigid

9

Bacteria do not have a

nucleus

10

Bacteria have

a flagellum, plasmid and chromosomal DNA

11

Sperm and egg cells contain a

haploid nucleus

12

Light microscope

- uses light to magnify
- colour
- greatest magnification is x2000

13

Electron microscope

- uses electrons to view object
- greatest magnification x10 million
- clearer, more detail
- black and white

14

equation for magnification

magnification (M) = image size (I) ÷ actual size (A)

15

when calculation magnification

measure image in millimetres
multiply by 1000 to find in micrometres (μm)

16

1mm =

1000μm 

17

1m =

10^(3)mm
10^(6) micrometre
10^(9) nanometre
10^(12) picometre

18

parts of a light microscope

eyepiece
objective
stage
coarse and fine focusing wheel

19

label lines must not

cross

20

title diagram with

specimen and magnification

21

enzymes are

biological catalysts (speed up but can be used again) that control reactions in the body, specific to its substrate, affected by temperature, substrate concentration and pH

22

enzymes at lower temps

has less energy so the reaction is slower

23

enzymes are working fastest at

the optimum temperature

24

enzymes at high temps

become denatured and don't fit the active site

25

rate of reaction =

rate of reaction = 1/time

26

rate of enzyme reactivity v=can be measured by

comparing rate at one pH to another pH

27

solutes

dissolved substances

28

solutes move through cells by

diffusion and active transport

29

water moves through cells by

osmosis

30

diffusion (particles)

particles move form an area of high concentration to an area of low concentration down the concentration gradient through a partially permeable membrane

31

active transport (water)

molecules move form an area of low concentration to an area of high concentration against (up) the concentration gradient through a partially permeable membrane, requires energy from respiration

32

osmosis can be investigated by

calculating change of mass in potatoes in solutes of different concentration

33

equation for change in mass

%change in mass = final mass-initial mass/initial mass x 100% (2d.p.)

34

extended response 6 marks

describe the graph using values
explain clearly each part of the graph