B1-Cell biology

Question 1

Mitochondria function?

Answer 1

Carry out aerobic respiration to release energy to use.

Question 2

Nucleus function?

Answer 2

Controlls cell activity and contains DNA

Question 3

Cytoplasm function?

Answer 3

Provides a gel-like medium where many chemical reactions occur, holds organelle in place, contains dissolved nutrients and salts

Question 4

Cell membrane function?

Answer 4

Selectively permeable structure. Controls what goes in and out of the cell

Question 5

Ribosome function?

Answer 5

Carry out protein synthesis

Question 6

Cell wall function?

Answer 6

Made of cellulose, used for strength and support of the plant

Question 7

Capsule function?

Answer 7

Protects prokaryotic cells when they’re engulfed by other organisms, help retain moisture, help the cell stick to surfaces and nutrients

Question 8

Plasma membrane function?

Answer 8

Same as cell mebrane

Question 9

Pili function?

Answer 9

Small, hair-like structures on the surface of the cell that attach to other surfaces

Question 10

Vacuole function?

Answer 10

Filled with cell sap to keep the cell turgid

Question 11

Flagella function?

Answer 11

Tail like structure that assists in cellular locomotion

Question 12

Plasmid function?

Answer 12

Single extra loop of naked DNA carrying some advantageous, non-essential genes

Question 13

What is the nuleoid?

Answer 13

An area of the cytoplasm that contains the essential genetic material for the cell (the naked DNA)

Question 14

Equation for magnification?

Answer 14

M=I/A (must be same units)

Question 15

What are the parts of a light microscope?

Answer 15

Eyepiece lens
Arm
Stage
Objective lens
Diaphragm
Coarse adjustment knob
Fine adjustment knob
Clips
Revolving nose

Question 16

Definition of diffusion?

Answer 16

The net movement of particles down a concentration gradient, from an area of high to low concentration, until equilibrium is reached.

Question 17

Definition of osmosis?

Answer 17

The net movement of wate molecules down a concentration gradient, from an area of high concentration, to low concentration across a semi-permeable cell membrane until equilibrium is reached.

Question 18

Active transport definition?

Answer 18

The net movement of particles against a concentration gradient, requiring energy from osmosis.

Question 19

Hypertonic cell meaning?

Answer 19

There is a higher water inside the cell than in the solution, so the water will move out (osmosis), causing the cell to shrivel

Question 20

Hypotonic cell meaning?

Answer 20

There is a higher water concentration outside the cell than inside, so water moves into the cell (osmosis) and cause it to swell

Question 21

Isotonic cell meaning?

Answer 21

The water concentration in the cell and outside is the same

Question 22

What are the pros and cons of a light microscope?

Answer 22

+Portable
+Easy to use
+Cheap
+You can see living specimens
-Low resolution
-Not good enough to study sub-cellular structures

Question 23

What are the pros and cons of an electron microscope?

Answer 23

+Powerful
+High resolution
+Can see individual organelle
+High magnification
+3D image available
-Small FOV
-Expensive
-Hard to use

Question 24

When using a light microscope, what magnification should you start with and why?

Answer 24

The lowest magnification, as it has the largest FOV so that you can locate and frame the specimen properly for closer inspection

Question 25

How is a sperm cell specialised?

Answer 25

Streamlined head and long tail to aid swimming, many mitochondria to supply lots of energy, the acrosome has digestive enzymes which break down the outer layers of membrane of the egg cell.

Question 26

How are root hair cells specialised?

Answer 26

Large surface area for a faster rate of osmosis, lots of mitochondria to provide energy from respiration for active transport of mineral ions