4.1.1 Cell structure

Question 1

What are the two types of cells

Answer 1

Prokaryotic(no nuclues)
Eukaryotic(has nucleus)

Question 2

what are the differences between eukaryotic and prokaryotic cells

Answer 2

Prokaryotes are smaller; eukaryotes have membrane-bound organelles and a nucleus.

Question 3

What are plasmids?

Answer 3

Small circular DNA loops that carry advantageous genes like antibiotic resistance

Question 4

Components of both plant and animal cells (5)?

Answer 4

Nucleus, cytoplasm, cell membrane, mitochondria, ribosomes

Question 5

Additional plant cell components (3)?

Answer 5

Chloroplasts, permanent vacuole, cell wall

Question 6

function of nucleus?

Answer 6

Controls cellular activities

Question 7

Cytoplasm function?

Answer 7

Jelly like substance where chemical reactions take place

Question 8

function of cell membrane

Answer 8

controls what enters and leaves the cell

Question 9

function of mitochondria

Answer 9

site of aerobic respiration and releases energy from the cell

Question 10

function of ribosomes

Answer 10

protein synthesis

Question 11

what is the cell wall made of?

Answer 11

Cellulose

Question 12

function of the cell wall

Answer 12

help keeps the cells structure

Question 13

function of the chloroplats

Answer 13

jelly like substance where chemical reactions take place

Question 14

how to convert from meters to centimeters

Answer 14

times by 100

Question 15

how to convert to centimeters to millimeter

Answer 15

divide by 10

Question 16

how to convert millimeters to micrometers

Answer 16

times by 1000

Question 17

how to convert micrometers to nanometers

Answer 17

times by 1000

Question 18

equation to work out magnification

Answer 18

Magnification = (Size of Image) / (Actual Size of Object

Question 19

equation to work out image size

Answer 19

Image Size = Magnification x Actual Size

Question 20

equation to work out actual size

Answer 20

Actual Size = Image Size / Magnification

Question 21

function of the mirror

Answer 21

reflects light for thee microscope

Question 22

function of the coarse

Answer 22

moves the stage up and down

Question 23

state 3 reasons why we use a cover slip when making a slide

Answer 23

to flatten specimen
to hold specimen in place
to stop specimen drying out

Question 24

required practical preparing slides

Answer 24

1.put a small drop of water on the slide
2.use forceps to peel the inside of an onion
3.use the forceps to transfer it onto the slide
4.stain the onion cell with iodine
5.place coverslip at a 45* angle over the specimen

Question 25

what is magnifcation

Answer 25

how many times larger an image is than an object

Question 26

what is resolution

Answer 26

the ability to distinguish between two points

Question 27

explain 2 ways sperm cell is adapted for its function

Answer 27

Flagellum-for movement through the reproductive tract acroscome-contains enzyme to break down the surface of the egg

Question 28

explain 2 ways a nerve cell is adapted for its function

Answer 28

dendrites-to make many connections to other nerve c axon-long and thin to carry impulses from one area of of the body to another e

Question 29

explain 2 ways a root hair cell is adapted for its function

Answer 29

long and thin so has a larger surface area large vacuole to speed up movement of water by osmosis

Question 30

what is cell differntiation

Answer 30

the process by which cells become specialised

Question 31

why is cell differentiation important

Answer 31

allow production of different tissues and organs that perform various vital functions in the human body

Question 32

what is a stem cell

Answer 32

an unspecialised cell which is capable of differentiating into other cell types

Question 33

What is the function of stem cells in embryos?

Answer 33

Embryonic stem cells can replicate and differentiate into many cell types. They may treat conditions like paralysis and diabetes by replacing damaged cells.

Question 34

What is the function of stem cells in adult bone marrow?

Answer 34

Adult stem cells can become several types of blood cells to replace dead or damaged tissue.

Question 35

What is the function of stem cells in plant meristems?

Answer 35

They can differentiate into any type of plant cell throughout the plant’s life.

Question 36

What is therapeutic cloning?

Answer 36

A technique where an embryo is made with the same DNA as a patient. The resulting stem cells won’t be rejected and can be used to treat disease.

Question 37

What are the advantages of cloning plants using meristem stem cells?

Answer 37

Prevents extinction of rare plants Produces large numbers with desired traits Makes identical plants for research

Question 38

What are the issues associated with the use of embryonic stem cells?

Answer 38

Ethical/religious objections (from aborted embryos) Stem cell therapy is slow, expensive, and complex Risk of viral infection transmission Immune rejection if donor cells are genetically different

Question 39

Describe how you would prepare a microscope slide using onion tissue

Answer 39

peel off epidermal layer using forceps place sample on a drop of water on microscope slide add drops of iodine solution to sample lower cover slip onto sample using mounting needle

Question 40

why is a thin sample of tissue required

Answer 40

allows light to pass through so internal structures can be observed

Question 41

why is water added to the slide efore the sample is mounted

Answer 41

allows the sample to be suspended between the slide and thee cover slip and ensure it stays in place

Question 42

why is the cover slip lowered using a mounting needle

Answer 42

ensure that no air bubbles are trapped