Cells- Topic 1- Cells

Question 1

What is Cell Theory?

Answer 1

• all living things are made from one or more cells
  -The cell is the basic unit of life
  -all cells come from pre-existing cells

Question 2

What is the function of the cell membrane?

Answer 2

The cell membrane controls the entry and exit of substances into a cell

Question 3

What are the elements that compose the phospholipid bilayer?

Answer 3

1. Hydrophilic phosphate heads.
2. Hydrophobic lipid tails.

Question 4

Describe and represent the fluid mosaic model of the cell membrane.

Answer 4

Fluid, as phospholipids and proteins are not fixed in place and can move around freely. A mosaic, as the pattern formed by phospholipids and proteins is similar to a mosaic of shapes.

Question 5

Describe the structure and function of the nucleus

Answer 5

Structure: contains DNA and has a double membrane with pores
Function: Have genes that code for proteins

Question 6

Describe the structure and function of the nucleolus

Answer 6

Structure: Contains RNA and proteins.
Function: Synthesis of ribosomes

Question 7

Describe the structure and function of the mitochondria

mention DNA

Answer 7

Structure: Double membrane, with cristae (folded inner membrane). Circular unbound DNA and ribosomes.
Function: Aerobic respiration and the production of ATP. Folded membranes and cristae increase the surface area and the number of enzymes for respiration.

Question 8

Describe the structure and function of the chloroplast. What is the purpose of thykaloids being stacked as grana?

Answer 8

Structure: Double membrane/contains thylakoids stacked as grana/Chlorophyll on thylakoids/circular unbound DNA/ribosomes.
Function: Chlorophyll is used in photosynthesis to capture light energy. Thylakoids being stacked as grana increase:
1. surface area
2. amount of chlorophyll
3. the amount of light energy absorbed.
4. rate of photosynthesis

Question 9

Describe the structure and function of the vacuole

Answer 9

Structure: sac of fluid that is big in plants and small in animals
Function: Maintains shape (plant) or stores nutrients (animals).

Question 10

Describe the structure and function of the Golgi Body

Answer 10

Structure: Made of unconnected flattened discs with small vesicles surrounding.
Function: Modify, package, and secrete proteins into vesicles for exocytosis. Synthesises lysosomes.

Question 11

Describe the structure and function of a vesicle

Answer 11

Structure: Membrane-bound sacs.
Function: Transports and stores substances

Question 12

Describe the structure and function of the RER

Answer 12

Structure: Single membrane which is hollow. Ribosomes attached.
Function: Synthesises proteins (ribosomes) and transports them to Golgi body.

Question 13

Describe the structure and function of the SER

Answer 13

Structure: Single membrane which is hollow. No ribosomes attached.
Function: Synthesises lipids.

Question 14

Describe the structure and function of ribosomes

Answer 14

Structure: Made of ribosomal RNA and proteins.
Function: Synthesises proteins.

Question 15

Describe the structure and function of a lysosome

Answer 15

Structure: Vesicle with digestive enzymes
Function: Digestion

Question 16

Describe the structure and function of the cytoskeleton

Answer 16

Structure: made of protein filaments and tubules
Function: provides structural support, helps in cell movement, and facilitates intracellular transport

Question 17

What are the two organelles that plant cells have that animal cells don’t have

Answer 17

Chloroplast and cell wall