UNIT 2- Cells: The Basic Unit Of Life

Question 1

Cell membrane function

Answer 1

1. Protects cell
2. Keeps contents of the cell together
3. Surrounds organelles
4. Controls exchange of substances into/ out of cell

Question 2

Nucleus function

Answer 2

1. Controls metabolic activities

2. Houses hereditary material in chromosomes

Question 3

Nucleus description

Answer 3

1. Found in every true cell
2. Largest cell organelle
3. 4 main parts:
   • nuclear membrane- double membrane with
   Nuclear pores - entrance to nucleus
   • nucleoplasm
   • chromatin network- made up of DNA, fine strands suspended/ scattered in nucleoplasm
   • nucleolus- made up of proteins and RNA

Question 4

Cytoplasm description

Answer 4

1. Consists of organelles suspended in cytosol
2. Cytosol-
   • water
   • cellular inclusions
   Fat globules and starch grains
   • solutes
   Sugar and salts
   • gases
   CO2 and O2

Question 5

Cytoplasm function

Answer 5

1. Fills cells

2. Surrounds and suspends organelles

Question 6

Cell membrane description

Answer 6

1. Extremely thin
2. Bilayer made from phospholipids
3. It is dynamic: phospholipids and proteins can move, creating channels for substances.
4. Selectively permeable- chooses substances that pass in/ out