B1: Cell Biology

Question 1

Name five subcellular structures that both plant and animal cells have:

Answer 1

Nucleus, cytoplasm, cell membrane, mitochondria and ribosomes

Question 2

What three things do plant cells have that animal cells do not?

Answer 2

Cell wall, permanent vacuole and chloroplasts

Question 3

Where is the genetic material found in animal cells?

Answer 3

The nucleus

Question 4

Where is the genetic material found in bacterial cells

Answer 4

The plasmids

Question 5

What type of organisms are bacteria: prokaryotes or eukaryotes?

Answer 5

Prokaryotes

Question 6

Which gives a higher resolution: a light microscope or an electron microscope?

Answer 6

An electron microscope

Question 7

What is cell differentiation?

Answer 7

Where a cell changes to become specialised for it’s job

Question 8

Give three ways that a sperm cell is adapted for swimming to an egg cell:

Answer 8

Long tail, streamlined shape, and contains enzymes to break the surface of the egg

Question 9

Why are nerve cells so shaped?

Answer 9

So that the branches can form networks with other nerve cells throughout the body

Question 10

What are chromosomes?

Answer 10

Chromosomes are coiled up lengths of DNA molecules

Question 11

What is the cell cycle?

Answer 11

A cycle to make new cells for growth, development and repair

Question 12

What is mitosis used for by multi-cellular organisms?

Answer 12

Creating exact replicas of specific cells within the body

Question 13

What is the name of the process by which bacteria divide?

Answer 13

Binary fission

Question 14

What is the maximum temperature a which bacteria should be grown in a school lab?

Answer 14

25 degrees celcius

Question 15

Give three precautions that could be taken to culture an uncontaminated sample of bacteria:

Answer 15

Sterilise the Petri dish, use inoculating loop, tape the edges of the dish lid down to avoid entry of harmful bacteria

Question 16

Give two ways that embryonic stem cells could help to treat disease:

Answer 16

Replacing faulty cells, and by therapeutic cloning of the embryo

Question 17

Why could some be opposed to human embryo use in stem cell research?

Answer 17

Each one is a potential human life that should not be wasted.

Question 18

What is diffusion?

Answer 18

Movement of particles from an area of high concentration to an area of low concentration

Question 19

Name three substances that can diffuse through membranes and two that can’t:

Answer 19

Glucose, oxygen and water can diffuse through cell membranes whereas starch and proteins cannot

Question 20

What type of molecule moves by osmosis?

Answer 20

Water molecules

Question 21

Give the two main differences between active transport and diffusion:

Answer 21

Uses glucose and the flow of particles is against the concentration gradient

Question 22

Give three adaptations of exchange surfaces that increase the efficiency of diffusion:

Answer 22

Thin, membrane, large surface area and lots of blood vessels

Question 23

Give two ways that the villi in the small intestine are adapted for absorbing food:

Answer 23

Single layer of surface cells and a very good blood supply along with a large surface area

Question 24

Explain how leaves are adapted to maximise carbon dioxide intake into their cells.

Answer 24

Large surface area and air spaces inside the leaf to make the cell wall exchange area larger