actual biology

Question 1

what is active transport

Answer 1

movement of particles from a low to high concentration (against a concentration gradient) across a partially permeable membrane

Question 2

what is the function of a cell membrane

Answer 2

controls movement of substances into and out of the cell

Question 3

name the structure that carries out photosynthesis in plants

Answer 3

chloroplast

Question 4

what is the function of vacuole

Answer 4

filled with cell sap, important for keeping cells rigid to support the plant

Question 5

what is the function of the cell wall

Answer 5

made of cellulose that strengthens the cell and provides support

Question 6

what is differentiation

Answer 6

the process where cells become specialised

Question 7

when does differentiation happen in animlas

Answer 7

early stage of development

Question 8

how is a sperm cell adapted to carry out its function

Answer 8

a tail to swim to egg
lots of mitochondria for energy
enzymes to penetrate egg
big nucleus to hold genetic information

Question 9

what is resolution

Answer 9

the ability to distinguish between two separate points
affects how much detail it can show and how clear it is

Question 10

what is magnification

Answer 10

the ability to make small objects seem larger e.g. how big the image is

Question 11

what is the difference between light and electron microscope

Answer 11

electron microscopes have a higher resolution and magnification
light microscopes have a low resolution

Question 12

how much does a light microscope magnify

Answer 12

1500 times

Question 13

how much does an electron microscope magnify

Answer 13

2 million times

Question 14

name 2 pieces of laboratory equipment that you use to prepare cells to view using a microscope

Answer 14

slide
iodine

Question 15

how is magnification calculated

Answer 15

image size / object size

Question 16

what is cell division used for in adult animals

Answer 16

repair of damage such as wounds

Question 17

what chemical are chromosomes made up of

Answer 17

proteins and dna

Question 18

what is a small section of a chromosome

Answer 18

gene

Question 19

what happens in stage 1 of the cell cycle

Answer 19

cell growth
dna copies / 2 copies of each chromosome
increase number of ribosomes / mitochondria

Question 20

what happens in stage 2 of the cell cycle

Answer 20

one set of chromosomes moves to each end of the cell / nucleus divides

Question 21

what happens in stage 3 of the cell cycle

Answer 21

cytoplasm and cell membrane splits to form 2 genetically identical daughter cells

Question 22

how many chromosomes would there be in total in stage 1 of cell cycle

Answer 22

92 chromosomes

Question 23

give 1 reason why plant cells divide by mitosis

Answer 23

repair

Question 24

how are cells produced by mitosis

Answer 24

DNA /chromosomes copied - move to each end of the cell

Question 25

what scientific term describes the structure of DNA

Answer 25

double helix

Question 26

which 2 cell components are copied before the muscle cells start to divide

Answer 26

mitochondria ribosomes

Question 27

why do muscle cells need to divide by mitosis more often than most other cells

Answer 27

to repair the muscles

Question 28

what are stem cells

Answer 28

an undifferentiated cell capable of giving rise to more cells of the same type

Question 29

what types of cells can stem cells from human embryos differentiate into

Answer 29

most different types of human cells

Question 30

which type of stem cells are found in adult bone marrow

Answer 30

stem cells that can form many types of cells, including blood cells

Question 31

where is meristem tissue found

Answer 31

plants

Question 32

what is the role of the meristem tissue in plants

Answer 32

to differentiate into any type of plant cell throughout the life of the plant

Question 33

which medical conditions might be treated with stem cell therapy

Answer 33

diabetes and paralysis

Question 34

what is therapeutic cloning

Answer 34

producing an embryo sith the same genes as the patient

Question 35

why are stem cells from therapeutic cloning not rejected by the patients body

Answer 35

they have the same genes as the patient

Question 36

what are potential risks associated with the use of stem cells

Answer 36

transfer of viral infections

Question 37

why do some people object to the use of stem cells

Answer 37

ethical or religious reasons

Question 38

how can stem cells from plant meristems be used

Answer 38

to produce clones of plants quickly and economically

Question 39

how can cloning plants using meristem stem cells help protect rare species

Answer 39

by producing large numbers of identical plants to protect from extinction

Question 40

why might farmers want to clone crop plants using meristem stem cells

Answer 40

to produce large numbers of identical plants with special features, such as disease resistance

Question 41

what is one of the main advantages of using stem cells from therapeutic cloning in medical treatment

Answer 41

they are automatically adapted to the patients body

Question 42

in what way can the use of stem cells in medicine be considered contriversial

Answer 42

ethical and religious objections arise from their source, especially from embryos