B2.1

Question 1

diffusion

Answer 1

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

Question 2

active transport

Answer 2

movement of molecules against the concentration gradient from a low concentration to a high concentration

Question 3

what kind of process is diffusion?

Answer 3

a passive process, no energy is needed

Question 4

concentration gradient

Answer 4

a difference in concentration between 2 areas

Question 5

what kind of process is active transport?

Answer 5

it is a process that requires energy

Question 6

water potential

Answer 6

a measure of the ability of water to move

Question 7

osmosis

Answer 7

the net movement of water from a high water potential to a low water potential through a partially permeable membrane

Question 8

factors which affect the rate of diffusion

Answer 8

-concentration
-temperature
-distance across

Question 9

explain why tipping salt onto slugs kills them

Answer 9

-salt is a solute
-adding salt to the outside of the snail decreases the water potential
-this creates a concentration gradient
-so water moves via osmosis out of the snail

Question 10

crenation

Answer 10

cell crumples up as it has no water

Question 11

turgid

Answer 11

cell becomes swollen with water

Question 12

lysis

Answer 12

cell bursts

Question 13

flaccid

Answer 13

plant cell lacking water

Question 14

plasmalysed

Answer 14

plant cell shrinks due to water moving out of cell

Question 15

what are the parts of the cell cycle?

Answer 15

-interphase
-mitosis
-cytokinesis

Question 16

what percentage does interphase make up of the cell cycle?

Answer 16

90%

Question 17

what is interphase?

Answer 17

-growth
-replicates DNA

Question 18

what percentage does mitosis make up of the cell cycle?

Answer 18

10%

Question 19

what is mitosis?

Answer 19

type of cell division where a single parent cell divides into two identical daughter cells

Question 20

what is the purpose of mitosis?

Answer 20

-growth
-tissue repair
-cell replacement
-asexual reproduction

Question 21

what are the different phases of mitosis?

Answer 21

-prophase
-metaphase
-anaphase
-telophase

Question 22

prophase

Answer 22

(PREPARE) the nucleus disappears and the chromosomes coil up to prepare for mitosis, spindle fibers start to form

Question 23

metaphase

Answer 23

(MIDDLE) chromosomes line up in the middle of the cell

Question 24

anaphase

Answer 24

(AWAY) chromatids are separated and pulled to opposite ends of the cell

Question 25

telophase

Answer 25

(TWO) the nuclei reform around each set of chromosomes, the chromosomes uncoil and the cell prepares for cytokinesis

Question 26

meristems

Answer 26

plant stem cells found in areas of new growth

Question 27

potency

Answer 27

a measure of how many types of specialised cells a stem cell can make

Question 28

pluripotent

Answer 28

can make all types of specialised cells in the body --> embryonic stem cells are pluripotent

Question 29

multipotent

Answer 29

can make multiple types of specialised cells but not all types --> adult stem cells are multipotent

Question 30

stem cells

Answer 30

undifferentiated cells that can replicate themselves or produce specialised cells through differentiation

Question 31

slef renewing cells

Answer 31

maintains the number of stem cells

Question 32

differentiating stem cells

Answer 32

makes 4 specialised cells to replace dead or damaged cells throughout your life

Question 33

potential uses of stem cells

Answer 33

-spinal cord injury -diabetes -deafness -blindness

Question 34

how do you calculate actual size?

Answer 34

image size / magnification

Question 35

differentiation

Answer 35

the process by which cells become specialized to perform specific functions in an organism

Question 36

function of red blood cells

Answer 36

to deliver oxygen tissues

Question 37

adaptations of red blood cells

Answer 37

-haemoglobin to bind to oxygen -no nucleus to have more space for haemoglobin -flexible to squeeze through capillaries -biconcave to increase surface area to volume ratio

Question 38

function of white blood cells

Answer 38

fights off infections

Question 39

adaptations of white blood cells

Answer 39

-has a lobed nucleus to make it more flexible -flexible to squeeze through blood vessels

Question 40

function of sperm cells

Answer 40

deliver genetic information to an egg cell

Question 41

adaptations of sperm cells

Answer 41

-flagellum to swim to the egg -has lots of mitochondria to produce energy -enzymes to break down the eggs cell membrane

Question 42

function of palisade cells

Answer 42

plant cells that carry out photosynthesis

Question 43

adaptations of palisade cells

Answer 43

-has chloroplasts with chlorophyll to carry out photosynthesis -large vacuole to store water, minerals and sugars

Question 44

function of root hair cells

Answer 44

absorb water for plants

Question 45

adaptations of root hair cells

Answer 45

-elongated shape to reach more water -large vacuole to store water

Question 46

where can meristems be found?

Answer 46

-roots -shoot apical -stem

Question 47

why can differentiated cells not divide in the plant?

Answer 47

they have no cell wall

Question 48

where can stem cells be found?

Answer 48

-embryo -foetus

Question 49

why are stem cells so useful?

Answer 49

they can repair damaged and diseased organs

Question 50

what type of cells do bone marrow stem cells differentiate into?

Answer 50

blood cells

Question 51

where can adult stem cells be found?

Answer 51

-eye -bone marrow

Question 52

why is it useful to produce organs using the patients own stem cells?

Answer 52

so it doesn't cause an infection