Topic 1

Question 1

What is in a bacterial cell?

Answer 1

• Chromosomal DNA (no nucleus) floats freely in cytoplasm and controls activities and replication.
• Ribosomes
• Cell membrane
• Plasmid DNA helps with drug resistance.
• Flagellum moves towards nutrients and away from toxins.

Question 2

Name 3 cells and how they are specialised.

Answer 2

Egg Cell:
- Contains nutrients to feed the embryo.
- Has a haploid nucleus.
- After fertilisation its membrane changes structure to prevent extra sperm getting in.
Sperm:
- Flagellum to swim.
- Lots of mitochondria for energy to swim.
Ciliated Epithelial Cell:
- Cilia move substances along.
- It does this with mucus in the lungs and moves it to the throat to be swallowed.

Question 3

What is the equation for magnification?

Answer 3

Magnification=image size/ Real size

Question 4

What do different enzymes break down?

Answer 4

• Carbohydrases convert carbs to simple sugars
• Protease convert proteins to amino acids
• Lipids convert lipids to glycerol and fatty acids.

Question 5

What are the 3 types of movement?

Answer 5

Diffusion- Net movement of particles from an area of high to low concentration.

Osmosis- Net movement of water molecules across a partially permeable membrane from an area of high to low water concentration.

Active transport- Movement of particles across a membrane against a concentration gradient using energy.