Foundation: B1 - Cell Biology

Question 1

What is a eukaryotic cell?

Answer 1

A cell that has its genetic material in a nucleus, eg. an animal cell.

Question 2

What is a prokaryotic cell?

Answer 2

A cell taht has a single loop of DNA in the cytoplasm, not in a nucleus, eg. a bacterial cell.

Question 3

What is the function of the nucleus?

Answer 3

Contains genetic information (DNA).

Question 4

What is the function of the cytoplasm?

Answer 4

Where chemical reactions take place in the cell.

Question 5

What is the function of the cell membrane?

Answer 5

Controls what enters & exits the cell.

Question 6

What is the function of the mitochondria?

Answer 6

Where aerobic respiration occurs.

Question 7

What is the function of the ribosomes?

Answer 7

Make proteins

Question 8

What is the function of the chloroplasts?

Answer 8

Where photosynthesis occurs

Question 9

What is the function of the vacuole?

Answer 9

Stores sap

Question 10

What is the function of the cell wall?

Answer 10

Strengthen the cell

Question 11

What is a cell wall made of?

Answer 11

Cellulose

Question 12

Which cell parts are found only in plants?

Answer 12

Chloroplasts, cell wall, vacuole

Question 13

How is a muscle cell specialised?

Answer 13

Has lots of mitochondria to do lots of respriation to supply lots of energy to the cell.

Question 14

How is a sperm cell specialised?

Answer 14

Has a tail (flagellum) to swim to the egg, lots of mitochondria to do lots of respiration to supply lots of energy for swimming.

Question 15

How is a nerve cell specialised?

Answer 15

Has a very long body to carry electrical impluses throughout the body, can make lots of connections with other nerve cells.

Question 16

How is a root hair cell specialised?

Answer 16

Has a large surface area for efficient absorption of substances from the soil

Question 17

How is xylem specialised?

Answer 17

Dead cells with no top or bottom to form a continuous column to transport water and support the plant.

Question 18

How is phloem specialised?

Answer 18

Sieve plates at the ends of cells allow substances to travel through the plant.

Question 19

What is cell differentiation?

Answer 19

When an unspecialised cell becomes specialised.

Question 20

What type of microscope is used in schools?

Answer 20

Light microscope

Question 21

What type of microscope has very high magnification and resolution?

Answer 21

Electron microscope

Question 22

What is the equation to calculate magnification?

Answer 22

Magnification = image size / actual size

Question 23

What is mitosis?

Answer 23

How body cells divide.

Question 24

What are the stages of the cell cycle?

Answer 24

1. The cell grows, makes more organelles and replicates DNA so there are two copies of each chromosome.
2. One set of chromosomes is pulled to each end of the cell and the nucleus divides.
3. The cytoplasm and cell membrane divides to form two idientical cells.

Question 25

Why does mitosis occur?

Answer 25

For growth and repair.

Question 26

What is a stem cell?

Answer 26

An undifferentiated cell of an organism that cen differentiate into many different types of cells.

Question 27

What is the difference between embryonic and adult stem cells?

Answer 27

Adult stem cells can differentiated into some types of cells, embryonic stem cells can differentiate into most types of cells.

Question 28

What is a meristem cell?

Answer 28

A stem cell found in the roots and shoots of plants.

Question 29

What is diffusion?

Answer 29

The movement of particles from an area of high concentration to an area of low concentraion. The particles move down a concentration gradient. This is a passive process so it does not use any energy.

Question 30

What is osmosis?

Answer 30

The movement of water particles from a dilute soltion to a more concentrated solution, through a partially permeable membrane. This is passive process so it does not require energy.

Question 31

What is active transport?

Answer 31

The movemebt of particles from an area of low concentration to an area of high concentration. The particles move against a concentration gradient. This is an active process so it requires energy.

Question 32

What factors affect the rate of diffusion?

Answer 32

The difference in concentrations (concentration gradient) The temperature The surface area of the membrane

Question 33

Where does diffusion occur in plants and animals?

Answer 33

Oxygen diffuses from the alveoli in the lungs into the red blood cells. Carbon dioxide diffuses from the atmosphere into leaves. Glucose diffuses from the small intestine into the blood.

Question 34

Where does active transport occur in plants and animals?

Answer 34

Glucose is absorbed from the small intestine into the blood at the end of the small intestine by active transport. Some mineral ions are absorbed from the soil into root hair cells by active transport.

Question 35

How are the lungs and small intestine adapted for efficient diffusion?

Answer 35

Large surface area Thin membrane Efficient blood supply