topic 1 - cell biology

Question 1

animal and plant cells are examples of what

Answer 1

eukaryotes

Question 2

bacteria cells are examples of what

Answer 2

prokaryotes

Question 3

similarities of animal and plant cells

Answer 3

cell membrane
nucleus
cytoplasm
mitochondria
ribosomes

Question 4

plant cell differences are

Answer 4

cell wall
permanent vacuole
chloroplast

Question 5

what do bacteria cells consist of

Answer 5

cell membrane
cell wall
ribosomes
cytoplasm
circular strands of dna
flagella
plasmids

Question 6

magnification equation

Answer 6

magnification=image size/object size

Question 7

key features of sten cells

Answer 7

they divide by mitosis to form more crlls
also able to differentiate into specialised cells

Question 8

embryonic stem cells

Answer 8

can differentiate into any type of cell

Question 9

where are adult stem cells found and what can they differentiate into

Answer 9

in bone marrow
platelets white blood cells and red blood cells

Question 10

where are plant stem cells found and what do they differentiate into

Answer 10

in the meristem
phloem and xylem cells
palisade cell
root hair cell

Question 11

key points specialised cells

Answer 11

specialised cells have a specific role in the body to help them fulfil that role they have a specific shape or structure

Question 12

differentiation meaning

Answer 12

the process by which cells become specialised

Question 13

cause of type 1 diabetes

Answer 13

damage to the pancreas cells that normally produce insulin

Question 14

sometimes the cause of paralysis is

Answer 14

damaged nerve cells

Question 15

draw backs of embryonic stem cells

Answer 15

requires embryonic stem cells
limited supply
ethically issues such as potential for human life other people think that the benefits of curing existing people who are suffering is more important
rejection from patient because patients genome is different

Question 16

risks of using stem cells in medicine

Answer 16

if the donor stem cells are infected with a virus then when there transferred to patient it will infect the patient

another risk would be tumor development since stem cells divide so quickly they could be out of control once theyve been transplanted and could develop into a tumor/cancer

Question 17

what is diffusion

Answer 17

Diffusion is the spreading out of the particles of any substance in solution, or particles of a gas, resulting in a net movement from an area of higher concentration to an area of lower concentration.

Question 18

what affects diffusion

Answer 18

Two factors affect diffusion:

The type of substance - substances diffuse more quickly through gases than through liquids. This is because the particles in a gas are more spread out and move faster than the particles in a liquid.

Temperature - the hotter the gas or liquid, the faster diffusion happens. This is because the particles have more energy and move faster at higher temperatures.

Question 20

what is osmosis

Answer 20

osmosis is the net movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration

Question 21

what is active transport

Answer 21

movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration and requiring energy from cellular respiration

Question 22

where is active transport used

Answer 22

used in plants specifically in the root hair cells

Question 23

what minerals does active transport deal with

Answer 23

magnesium ions and nitrates

Question 24

how are root hair cells adapted to their role

Answer 24

root hair cells use active transport to absorb mineral ions and are adapted to that role because of having a large surface area and lots of mitochondria

Question 25

what are specialised exchange surfaces

Answer 25

the parts of an organism over which they exchange substances with their environment

Question 26

examples of specialised exchange surfaces and what they do

Answer 26

alveoli which is used to exchange oxygen and carbon dioxide
villi used to absorb nutrients such as glucose and amino acids

Question 27

common features specialised exchange surfaces share

Answer 27

1)large surface area so lots of molecules can diffuse across at the same time so higher rate of diffusion
2)exchange surfaces are usually very thin so diffusion can take place more quickly
3)exchange surfaces are permeable to the substances that need to exchange