Chapter 1

Question 1

What is osmosis?

Answer 1

The movement of water from a high concentration to a low one through a partially permeable membrane

Question 2

Why do plants rely on osmosis?

Answer 2

To stay turgid

Question 3

What is active transport?

Answer 3

When a dissolved substance moves against the concentration across a partially permeable membrane

Question 4

Where does the energy for active transport come from?

Answer 4

Cell respiration

Question 5

What does against the concentration gradient mean?

Answer 5

From a dilute solution to a more concentrated solution

Question 6

How are nerve cells specialised?

Answer 6

Lots of dendrites to make connections to other nerve cells
Axon to carry impulse from one place to another
Lots of mitochondria to provide energy to make chemicals needed
long to cover longer distances

Question 7

How are muscle cells specialised?

Answer 7

Special proteins make the fibres contract
Many mitochondria to transfer energy needed to contract and relax
Store glycogen which is used by mitochondria

Question 8

How are sperm cells specialised?

Answer 8

Long tail and streamlines head
Many mitochondria
Digestive enzymes to break down egg wall
Large nucleus containing DNA to be passed on

Question 9

Root hair cell adaptions

Answer 9

Large SA for water to move into cell
Large permanent vacuole to speed up osmosis
Many mitochondria to make energy needed for active transport of minerals into roots

Question 10

How are photosynthetic cells adapted?

Answer 10

Contain chlorophyll
Positioned in outer layers of plant
Large permanent vacuole to keep cells and plant rigid

Question 11

How are xylem cells adapted?

Answer 11

Hollow insides to allow water and minerals to move easily

Spirals of lignin in walls makes cells very strong

Question 12

How are phloem cells adapted?

Answer 12

very few subcellular structures so stuff can flow through

Supported by companion cells that transfer mitochondria needed to move food

Question 13

What is diffusion?

Answer 13

The spreading out of particles from a high concentration to a low one

Question 14

How do you calculate the magnification of an object?

Answer 14

Magnification = size of image/size of real object

Question 15

What is the rate of diffusion affected by?

Answer 15

The difference in concentrations
Temperature
Available surface area

Question 16

Examples of substances that move by diffusion

Answer 16

Glucose
Urea (from liver to blood plasma)
Oxygen (from lungs to RBCs)

Question 17

What is a dilute solution?

Answer 17

High concentration of water

Low concentration of solute

Question 18

What is a concentrated solution?

Answer 18

Low concentration of water

High concentration of solute

Question 19

What does isotonic mean?

Answer 19

Concentration of solute so in solution outside of cell is same as inside

Question 20

What does hypertonic mean?

Answer 20

Concentration of solutes in solution is higher than inside cell

Question 21

What does hypotonic mean?

Answer 21

Concentration of solutes in solution outside cell is lower than inside

Question 22

Problems with osmosis

Answer 22

If solution outside cell is much more dilute, then water will move into cell by osmosis so will burst

If the solution outside cell is much more concentrated, then water will move out of cell and cell will shrivel up and die

Question 23

Why do plants want the solution around cells do be hypertonic?

Answer 23

Water will keep moving by osmosis into the cell

Question 24

What is plasmolysis?

Answer 24

When the vacuole and cytoplasm shrink and the cell membrane moves away from cell wall because of lack of water

Question 25

What do cells involved in active transport have lots of?

Answer 25

Mitochondria to get maximum energy

Question 26

Why is active transport so important?

Answer 26

Mineral ions in the soil are found in low concentrations so by using active transport, the plants can absorb these minerals Sugar

Question 27

What is key about single called organism when it comes to diffusion, active transport and osmosis?

Answer 27

Relatively high surface area to volume ratio

Question 28

Adaptions for exchanging materials

Answer 28

Large SA to volume ratio Thin membrane - short diffusion path Efficient blood supply Ventilation

Question 29

How is the human body adapted for exchange?

Answer 29

Alveoli increase SA

Question 30

How are fish adapted for exchange?

Answer 30

Gills increase SA

Question 31

How are plants adapted for gas exchange?

Answer 31

Flat and thin leaves | Air spaces and stomata make a big SA

Question 32

equation for magnification

Answer 32

size of image / size of real object

Question 33

what is 1 nanometre?(nm)

Answer 33

1 x 10-9 metres

Question 34

what is a micrometre? (up)

Answer 34

1000 nanometres

Question 35

what is the resolving power of a microscope?

Answer 35

how much detail it can show

Question 36

function of nucleus

Answer 36

contains activities of the cell

Question 37

function of cytoplasm

Answer 37

where chemical reactions take place

Question 38

function of cell membrane

Answer 38

controls movement of substances in and out

Question 39

function of mitochondria

Answer 39

create energy

Question 40

function of ribosomes

Answer 40

protein synthesis

Question 41

which organelles are common to both animal and plant cells

Answer 41

``` nucleus membrane mitochondria ribosome cytoplasm ```

Question 42

function of cell wall

Answer 42

strengthens and supports cell

Question 43

what is the cell wall made from

Answer 43

cellulose

Question 44

function of chloroplasts

Answer 44

contain chlorophyll for photosynthesis

Question 45

function of vacuole

Answer 45

fills with water to keep cell turgid

Question 46

what is an eukaryotic cell?

Answer 46

contains a nucleus with DNA

Question 47

what is a prokaryotic cell?

Answer 47

single-celled - no nucleus | genetic material in loop or plasmids

Question 48

organelles exclusive to bacteria cells

Answer 48

flagella, plasmids and slime capsule

Question 49

function of flagella

Answer 49

move cell

Question 50

function of slime capsule

Answer 50

protect cell

Question 51

what characteristics should a good exchange surface hav?

Answer 51

large SA thin walls good blood supply well ventilated

Question 52

what is a tissue?

Answer 52

a group of cells working together to perform a specific function

Question 53

what does muscular tissue do?

Answer 53

contracts to churn contents of stomach

Question 54

what does glandular tissue do?

Answer 54

produces hormones

Question 55

what does epithelial tissue do?

Answer 55

covers inside and outside of all orgns

Question 56

why might you add stain to a microscope slide

Answer 56

to highlight certain objects by adding colour

Question 57

what is the purpose of active transport in the gut?

Answer 57

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

Question 58

how are alveoli adapted for gas exchange?

Answer 58

huge SA thin good blood supply

Question 59

how is the small intestine adapted for gas exchange?

Answer 59

villi - increase SA good blood supply thin walls

Question 60

how are leaves adapted for gas exchange?

Answer 60

the stomata let CO2 in and H2O and O2 out size of stomata can be controlled by guard cells air spaces in leaf increase SA flat shape increases SA

Question 61

how are fish (gills) adapted for gas exchange?

Answer 61

gill filaments increase SA short diffusion pathway good blood supply always more O2 in water than blood so steep concentration gradient means it is more effective

Question 62

advantage of light microscope

Answer 62

relatively cheap

Question 63

advantage of electron microscope

Answer 63

much higher resolving power

Question 64

how big is the average animal cell?

Answer 64

10 - 30 micrometres

Question 65

how big is the average plant cell?

Answer 65

10 - 100 micrometres

Question 66

why can diffusion take place without respiration

Answer 66

doesn't need energy supply

Question 67

what is the name for the apparatus which is a stick with a hoop on

Answer 67

innoculating loop

Question 68

what are the drugs called that people with malaria are given

Answer 68

antiretrovirals

Question 69

How do plants grow?

Answer 69

Photosynthesis Creates glucose This is used in respiration To produce energy

Question 70

Why are stem cells from embryos so good?

Answer 70

They are versatile and can differentiate to most cell types

Question 71

What are flagella made from?

Answer 71

They are strings of protein