Definitions

Question 1

Diffusion

Answer 1

Diffusion is the net random movement of particles from an area of high concentration to an low concentration, diffusion requires no energy.

Question 2

Phogocytes

Answer 2

Phagocytes are white blood cells that “engulf” pathogens. When they don’t recognise their receptors (antigens).

Question 3

Lymphocytes

Answer 3

Lymphocytes are white blood cells that only recognise the receptors/antigens on one specific pathogen.

Question 4

Health

Answer 4

Health is the state of physical and mental well-being.

Question 5

What is DNA?

Answer 5

DNA stands for deoxyribonucleic acid. It’s chemical that all of the genetic material in a cell is made up from. It contains coded information - the instructions to put an organism together and make it work. So it determines what inherited characteristics you have. DNA is found in the nucleus of plant and animal cells in really long strands called chromosomes, which come in pairs, DNA is a polymer, it’s made from up of 2 strands coiled together in the shape of a double helix.

Question 6

Osmosis

Answer 6

Is the movement of water molecules from an area of high concentration to an area of low concentration across a partially permeable membrane. No energy is needed.

Question 7

Active transport

Answer 7

Molecules move from an area of low concentration to an area of high concentration. The process requires ATP energy and carrier proteins in the cell membrane.

Question 8

Stem cells

Answer 8

A stem cell is a cell that is unspecialised. This means that the cell can replicate many times and has the become specialised (different types of cells)