B1 Cell biology Flashcards Preview

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Flashcards in B1 Cell biology Deck (61):
1

What are all living things made up of?

cells

2

What if the difference between a prokaryotic cell and a eukaryotic cell?

the prokaryotic cell has no neucleusProkaryote is simpler

3

What is the function of the nucleus?

To contain genetic material that controlling the activities the cell

4

What is the function of the cytoplasm?

The site where most chemical reactions happen

5

What is the function of the cell membrane?

To hold the cell together and controls what goes in and out

6

What is the function of the mitochondria?

to help with aerobic respiration

7

What is the function of the ribosomes?

To make proteins via protein synthasis

8

What type of cell are bacteria?

prokaryotes

9

What is the formula for magnification?

image size/real size

10

Does a bacterial cell have a nucleus?

no

11

What is a plasmid?

a circular strand of DNA that floats freely in the cytoplasm

12

Do bacteria have mitochondria or chloroplasts?

no

13

What are chloroplasts?

where photosynthesis occurs. they make the food for the plant

14

What is cell differentiation?

a process where cells become specialised

15

What are sperm cells specialised for?

reproduction- streamlined head and ling tail

16

What are nerve cells specialised for?

rapid signalling- long and have branched connections

17

What are muscle cells specialised for?

contraction- long so they have space to contract

18

What are root hair cells specialised for?

absorbing water and minerals- big surface area

19

What are phloem and xylem cells specialised for?

transporting substances-long and hollow

20

What do chromosomes do?

contain genetic information

21

Why do we have 23 pairs of chromosomes?

Because we have one from the father and one from the mother

22

What is the function of the cell cycle?

make new cells for growth, development and repair

23

What is mitosis?

the stage in the cell cycle where the cell divides

24

How many stages are there in the cell cycle?

2

25

What happens in the growth and DNA replication stage?

cell grows and duplicates its DNAincreases sub cellular structures like mitochondria and ribosommes

26

What are the stages of Mitosis?

chromosones line upcell fibres pull them apart membarnes form about each set of chromosonescytoplasm and membrane divide

27

How do prokaryotic cells divide?

By binary fission

28

What occurs in binary fission?

plasmids replicatestrands move to opposite polescytoplasm begins to divide2 daughter cells are produced

29

A bacterial cell has a mean division time of 30 mins. how many times will it divide in 3 hours?

3 x 60= 180180/30=6 times

30

What temperature do we culture microorganisms at?

25 degrees

31

what are embryonic stem cells?

cells that can turn into many different types of cells

32

Where do we find stem cells?

human embryos

33

Can adult stem cells turn into any type of cell?

no

34

What is the difference between embryonic and adult stem cells?

Embryonic can turn into any type of cell Adult cant

35

How could adult stem cells be used in medicine?

bone marrow cells can replace faulty blood cells

36

How could embryonic stem cells be used in medicine?

to make insulin producing cells for diabetics

37

Why are some people against stem cell research?

because they feel human embryos are potential human life and shouldn't be used for experiments

38

How can stem cells be used in plants?

to produce identical plants for farmers and help grow rare species

39

Where are stem cells found in plants?

the merristem

40

What is diffusion?

the movement of particles from an area of high concentration to an area of low concentration

41

What is Osmosis?

osmosis is the movement of water molecules from a region of high concentration to low concentration across a partially permeable membrane

42

What is active transport?

where substances are absorbed against the concentration gradient

43

What will happen in diffusion if there is a bigger concentration gradient?

the diffusion rate will increase

44

Does diffusion work in solids and liquids?

Solids- noLiquids- yes

45

What type of molecules can diffuse through cell membranes?

small molocules

46

Can oxygen diffuse?

yes

47

Can starch and proteins diffuse?

no`

48

What type of processes are osmosis and diffusion?

passive

49

What type of molecules move in osmosis?

water molocules

50

is energy required for active transport?

yes

51

Where is active transport used?

in the gut when there is a lower concentration of nutrients in the gut but a higher concentration in the blood

52

what do cells use diffusion for?

to take in and remove waste products

53

What is a surface area to volume ratio?

a measure of how easy it is for an organism to exchange substances with its environment

54

How are exchange surfaces adapted for maximum effectiveness?

thin membranelarge surface arealots of blood vesselswell ventilated

55

What is the surface area to volume ratio like on single celled organisms?

large

56

What is the surface area to volume ratio on multi cellular organisms?

small so specialist structures are needed

57

What is the function of the lungs?

To transfer oxygen to the blood and remove waste carbon dioxide

58

How are alveoli adapted for efficient gas exchange?

alveoli have....>enormous surface area >Moist lining

59

How is the small intestine adapted?

good blood supply villi have a large surface area for food to be absorbed more quickly

60

How are leafs adapted for efficient gas exchange?

stomata open and closelarge surface area

61

How are fish gills adapted for efficient gas exchange?

gill filaments provide a large surface arealots of blood capilaries speed up diffusionhigh concentration gradient ensures as much as possible is absorbed