Cells & Living Things

Question 1

Describe the main points of cell theory.

Answer 1

• Cells are the structural unit of all living things
• Cells are the functional unit of life; carrying out all living processes
• Every cell arises from a pre-existing cell
• Cells contain hereditary material

Question 2

What are the seven essential components that define life (MRS GREN)?

Answer 2

Movement, respiration, sensitivity, growth, reproduction, excretion and nutrition.

Question 3

All living things (6);

Answer 3

• are complex and have an organised structure
• take in energy from their surroundings and use it
• maintain a composition that is chemically different from their external environment
• respond to stimulus
• are able to reproduce
• grow and develop

Question 4

What is the cytoplasm?

Answer 4

Consisting of mainly water (cytosol) and organelles, it holds the components of a cell in place.

Question 5

What are the main functions of the cell membrane?

Answer 5

It separates the contents of the cell from the extracellular environment, regulates the passage of substances intercellularly, enables cells to recognise one another and other substances such as hormones, and enables attachment of the cytoskeleton.

Question 6

What is the cell membrane comprised of?

Answer 6

A phospholipid bilayer.