B1 - Cell Biology

Question 1

What are eukaryotic cells?

Answer 1

Cells which contain their genetic information inside a nucleus

Question 2

Give examples of eukaryotic cells

Answer 2

Plant, animal and amoebae cell

Question 3

What are prokaryotic cells?

Answer 3

Cells which don’t contain a nucleus and have their genetic information floating in the cytoplasm

Question 4

Give an example of a prokaryotic cell

Answer 4

Bacterial cells

Question 5

Is the bacteria smaller, equal in size or larger than animal and plant cells?

Answer 5

They are much smaller

Question 6

What is the function of the nucleus?

Answer 6

Stores genetic information

Question 7

What is the function of the cytoplasm?

Answer 7

This is where the chemical reactions take place

Question 8

What is the function of mitochondria?

Answer 8

They release energy from glucose in aerobic respiration

Question 9

What is the function of ribosomes?

Answer 9

They make proteins

Question 10

What is the function of the cell wall?

Answer 10

To give the cell strength

Question 11

What is the cell wall made up of?

Answer 11

Cellulose

Question 12

What is the function of chloroplasts?

Answer 12

Carry out photosynthesis

Question 13

What do chloroplast contain?

Answer 13

The pigment chlorophyll

Question 14

What is the function of chlorophyll?

Answer 14

Capture the sunlight energy to do photosynthesis

Question 15

What is the function of a permanent vacuole?

Answer 15

Contains cell sap and gives the cell structure and strength

Question 16

Which sub cellular structures are found in plant cells but not in animal cells?

Answer 16

Cell wall, permanent vacuole and chloroplasts

Question 17

What is the cell wall in bacterial cells made up of?

Answer 17

Peptidoglycan

Question 18

What is a plasmid in a bacterial cell?

Answer 18

A small ring of DNA found in bacterial cells

Question 19

What is the function of the flagellum in bacterial cells?

Answer 19

To allow movement

Question 20

What are the two types of microscopes?

Answer 20

Electron and light

Question 21

Why is the electron microscope better than the light one?

Answer 21

It has a higher magnification and resolution

Question 22

What does a higher magnification mean?

Answer 22

It can see smaller objects in more detail

Question 23

What does a higher resolution mean?

Answer 23

You can see things more clearly

Question 24

How do you calculate the magnification?

Answer 24

Image size / actual size

Question 25

What are the units of magnification?

Answer 25

X

Question 26

How many chromosomes are there in a normal body cell?

Answer 26

46

Question 27

How many pairs of chromosomes are there in a normal body cell?

Answer 27

23

Question 28

What is the cell cycle?

Answer 28

A few stages in which the cell cycle divides to make new cells

Question 29

What does a cell do before it divides?

Answer 29

Grow in size Increase the amount of sub cellular structures Duplicate the DNA

Question 30

What are chromosomes?

Answer 30

Long coiled up DNA molecules which carry genes

Question 31

Where are the chromosomes found?

Answer 31

In the nucleus

Question 32

How many copies are there made in mitosis?

Answer 32

2

Question 33

What are the two new cells made in mitosis called?

Answer 33

Daughter cell

Question 34

What is the original cell in mitosis called?

Answer 34

Mother/parent cell

Question 35

The new cells formed in mitosis are identical or different to the parent cell?

Answer 35

Identical

Question 36

Describe the steps in mitosis

Answer 36

``` The DNA doubles The chromosomes line up in the middle One set of chromosomes is then pulled to each end of the cell The cytoplasm and cell membrane divides Two new daughter cells are formed ```

Question 37

Why are cells dividing by mitosis?

Answer 37

Growth, development and repair

Question 38

What is differentiation?

Answer 38

The process by which a cell changes to become specialised for its job

Question 39

When can most animal cells differentiate?

Answer 39

At an early stage

Question 40

WHen can most plant cells differentiate?

Answer 40

At any point of time

Question 41

What is the function of muscle cells?

Answer 41

Contraction

Question 42

How are muscle cells specialised to carry out their function?

Answer 42

They have a lot of mitochondria for energy for contraction | They are long so have a lot of space to contract

Question 43

Name types of specialised animal cells

Answer 43

Sperm, muscle and nerve

Question 44

Name types of specialised plant cells

Answer 44

Root hair, xylem and phloem

Question 45

What is the function of a nerve cell?

Answer 45

Send rapid signals to the brain

Question 46

How is a nerve cell adapted to carry out its function?

Answer 46

It is long so it can cover a large distance | It is branched to form a large network of connections

Question 47

What is the function of a sperm cell?

Answer 47

Reproduction | To carry the male genetic information to the female’s genetic information

Question 48

How is the sperm cell adapted to carry out its function?

Answer 48

It has a long flagellum helping it to swim Has a lot of mitochondria for energy to swim to the egg Acrosome in the tip of the head contains enzymes that can break down the egg cell membrane

Question 49

What is the function of the xylem?

Answer 49

Carry water from the roots to the rest of the plant

Question 50

Is the direction of movement of water in the xylem upwards, downwards or in both direction?

Answer 50

Upwards only

Question 51

What is the function of the phloem?

Answer 51

Transport glucose from the leaves to the rest of the platn

Question 52

IS the transport direction nor glucose in phloem upwards, downwards or in both directions?

Answer 52

Both directions

Question 53

How are the xylem cells adapted to carry out its function?

Answer 53

They are hollow

Question 54

How are the phloem cells adapted to carry out its function?

Answer 54

They have few sub cellular structures so that glucose can flow through it more easily

Question 55

Name two type of animal stem cells

Answer 55

In the adult bone marrow and embryonic stem cells

Question 56

Where are the stem cells found in plants?

Answer 56

In the meristem

Question 57

What can the embryonic stem cells change into?

Answer 57

Any kind of human cell

Question 58

What can the adult bone marrow stem cells change into?

Answer 58

Most human cells

Question 59

What can the plant meristem stem cells change into?

Answer 59

Any kind of plant cells

Question 60

What are the risk of growing stem cells in a lab?

Answer 60

The stem cells can get contaminated with a virus which can be passed on to the patient

Question 61

What are the uses of stem cells in medicine?

Answer 61

For Type 1 diabetes patients to form cells which can make insulin For paralysed patients to make new nerve cells

Question 62

What is therapeutic cloning?

Answer 62

Making an embryo that has the same genetic information as the patient and using its stem cells to treat the patient

Question 63

What are the advantage of therapeutic cloning?

Answer 63

The stem cells will not be rejected by the patient’s body

Question 64

What are the two types of passive transport?

Answer 64

Diffusion and osmosis

Question 65

What are the properties of passive transport?

Answer 65

They don’t require energy and the particles move from a high to low concentration

Question 66

Give an example of diffusion in an animal

Answer 66

CO2 and O2 in the lungs | And glucose from the blood to the organs

Question 67

Define diffusion

Answer 67

Diffusion is the movement of particles from high to low concentration

Question 68

Which type of molecules can diffuse?

Answer 68

Only small molecules such as CO2, O2 and glucose

Question 69

Define osmosis

Answer 69

The movement of water molecules from a dilute to concentrated region

Question 70

Which factors increase the rate of diffusion?

Answer 70

High surface area (+) High temperature (+) A high concentration gradient (+)

Question 71

Why does a larger surface area increase diffusion?

Answer 71

There is more room for particle to move

Question 72

Why does an increase in temperature increase diffusion?

Answer 72

The particles move faster (increased kinetic energy)

Question 73

What is active transport?

Answer 73

Movement of particles against the concentration gradient using energy

Question 74

Where does the energy needed for active transport come from?

Answer 74

From respiration

Question 75

Give an example of active transport in plants

Answer 75

Mineral ions from the soil through the root hair cells

Question 76

Give an example of active transport in animals

Answer 76

Absorbing glucose (for cell respiration) into the bloodstream from the gut

Question 77

Do single felled organisms have a large or small SA: volume ratio?

Answer 77

Large

Question 78

What do single called organisms depend on for their substance exchange?

Answer 78

Diffusion

Question 79

Is diffusion only enough for multicellular organisms to carry out substance exchange?

Answer 79

No

Question 80

Do multi cellular organism have a small or large SA:volume ratio?

Answer 80

Small

Question 81

What do multicellular organism need to transport things in and out of the cell?

Answer 81

Exchange surfaces and transport systems

Question 82

What are the four things that exchange surfaces all have in common?

Answer 82

A large surface area A thin membrane Good and efficient blood supply (animals) Ventilation (in animals)

Question 83

What is the function of a large surface area in exchange surfaces?

Answer 83

So that more diffusion can take place

Question 84

What is the function of a thin membrane in exchange surfaces?

Answer 84

So that the particles can travel/diffuse over a shorter distance

Question 85

Name four organs that are adapted for exchange

Answer 85

Alveoli (in lungs) Villi in the small intestines Gills (in fishes) Leaves (in plant)

Question 86

How are leaves adapted to substance exchange?

Answer 86

They have a flat shape | They are exchanging gases through the stomata Between the air and the leave

Question 87

How are gills adapted to substance exchange?

Answer 87

They have a lot of thin surface layers of cells They a lot of capillaries They are exchanging gases between the water and blood

Question 88

How are the alveoli adapted to substance exchange?

Answer 88

There a lot of of them (increase surface area) They have thin membranes They have blood capillaries around them They are exchanging gases between the air and the blood

Question 89

How are the villi (small intestines) adapted to substance exchange?

Answer 89

They are very thin There are a lot of them There is a lot of blood capillaries around them They are exchanging food molecules from the gut/intestines into the blood