Chapter 1: Cells🧫

Question 1

Light microscope magnification and function

Answer 1

1000x, for coloured images of main structures

Question 2

Electron microscope magnification and function

Answer 2

200 000x, black and white images of smaller structures

Question 3

Protoplasm

Answer 3

Jelly-like substance where most cell activities are carried out

Consists of cell surface membrane, cytoplasm and nucleus

Question 4

Cell surface membrane

Answer 4

• Surrounds cytoplasm
• Made of lipids and proteins
• PPM: controls movement of substances

Question 5

Cell wall

Answer 5

• encloses plant cell
• made of cellulose
• protects cell from injury + fixed shape
• f fully permeable

Question 6

Cytoplasm

Answer 6

• most cell activities happen here
• mainly consists of water

Question 7

Organelles

Answer 7

Membrane bound cellular structure that performs a specific job within a cell

Question 8

Nucleus description

Answer 8

• surrounded by nuclear membrane
• consists of nucleoplasm
• contains genetic info in the form of chromosomes
• may contain nucleoli and chromatin

Question 9

Nucleus function

Answer 9

• controls cell activities: cell growth, repair of work out parts and protein synthesis
• essential for cell division

Question 10

Chromosomes

Answer 10

• Long thread-like structures (48 in human cell)
• made up of proteins and deoxyribonucleic acid (DNA: contains hereditary info)
• chromatin threads coil and condense into thick rod-like structures to become chromosomes when cell is dividing

Question 11

Rough endoplasmic reticulum (RER) appearance

Answer 11

• network of flattened spaces lined with membrane
• appears rough due to attached ribosomes
• outer surface of RER is continuous with the nuclear membrane

Question 12

RER function

Answer 12

Transports proteins to golgi apparatus for secretion out of cell

Question 13

Ribosomes (attached)

Answer 13

Attached to RER
Synthesises proteins that are transported out of cell

Question 14

Ribosomes (free)

Answer 14

Free in cytoplasm
Synthesises proteins used in cell

Question 15

Smooth endoplasmic reticulum (SER) appearance

Answer 15

No attached ribosomes
More tubular than RER
Connected to RER

Question 16

Smooth endoplasmic reticulum (SER) function

Answer 16

Synthesises substances: data and steroids
Concerts harmful substances to harmless ones (detoxification)

Question 17

Golgi Body / Golgi apparatus appearance

Answer 17

Stack of flattened spaces surrounded by membranes

Question 18

Golgi body / Golgi apparatus function

Answer 18

Stores and chemically modified substances made by ribosomes
Stores and packages these substances in vesicles for secretion out of cell

Question 19

Vesicle appearance

Answer 19

Tiny spherical spaces enclosed by membrane

Question 20

Vesicle function

Answer 20

Fuses with one side of Golgi body and pinches off the opposite side

Question 21

Vesicle process

Answer 21

1. Vesicles with substances from RER pinches off from RER
2. Vesicles fuse with Golgi body
3. Substances released into Golgi apparatus are modified and packaged
4. Secretory vesicles with substances pinch off Golgi body and move towards cell surface membrane
5. Secretory vesicles fuse with cell surface membrane and release substances into exterior of the cell

Question 22

Mitochondria

Answer 22

Site of aerobic respiration: food substances are broken down to release energy (oxidise glucose to release energy for cell activities like growth and respiration)

Question 23

Chloroplasts

Answer 23

Oval structures
Contain chlorophyll which absorbs light energy to carry out photosynthesis

Question 24

Vacuoles

Answer 24

Fluid-filled space enclosed by a ppm (tonoplast in plants)
Stores substances within a cell
Plant: large central vacuole containing cell sap
Animal: many small vacuoles containing water and food substances (exist temporarily)