Lecture 1

Question 1

What is the definition of cell

Answer 1

A cell is the basic unit of life. They can be unicellular or multicellular

Question 2

What are the three main principles of the cell theory?

Answer 2

1. All organisms have one or more cell
2. The cell is the structural unit of life
3. Cells can only occur from a pre-existing cell

Question 3

What is a prokaryotic cell

Answer 3

It is unicellular, has a simple structure, it’s bounded by a cell wall, are small. Eg bacteria

Question 4

What is a eukaryotes?

Answer 4

All organism except bacteria
Multicellular organisms, Protozoa and unicellular algae
Large and structurally complex
Consists of a nucleus enclosed by a membrane containing organelles
2 main compartments : nucleus & cytoplasm
Complex cytoskeleton
2 copies of each gene (1 from each parent)
Sexual reproduction can occur

Question 5

What is an organelle

Answer 5

A specialised cellular part that has a specific function

Question 6

Nucleus

Answer 6

• largest organelle
• visible under light microscope
• contains cellular DNA
• DNA visible at some stages of cell growth
• enclosed by a double membrane called nuclear envelope
• contains 1 or more spherical structures called nucleoli : site of synthesis of ribosomal RNA

Question 7

Endoplasmic Reticulum

Answer 7

• system of membranes connected to nuclear membrane
• controls transport of molecules within cell
• smooth, rough and sarcoplasmic

Question 8

Rough endoplasmic reticulum

Answer 8

Functions in protein synthesis

Protein translation and folding

Question 9

Smooth endoplasmic reticulum

Answer 9

Lipid biosynthesis

Membrane repair

Question 10

Sarcoplasmic reticulum

Answer 10

Stores calcium in muscle cells

Question 11

Golgi apparatus

Answer 11

• Series of flattened membrane-enclosed sacs & vesicles
• processing plant
• chemically modifies newly synthesised proteins
  Directs proteins outside cell or other cellular locations

Question 12

Lysosomes

Answer 12

Small irregularly shaped
Found in animal cells
Contains strong digestive enzymes
Breakdown foreign material & ingested micro organisms

Question 13

Peroxisomes

Answer 13

Micro bodies
Small single membrane
Found in plants and animals
Performs diverse metabolic reactions e.g. breakdown and generation of h202

Question 14

Mitochondria

Answer 14

• present in large numbers
• double membrane structure
• inner membrane arranged in folds cristae
• site of ATP production
• contain DNA deoxyribonucleic acid and RNA ribonucleic acid