Biology

Question 1

What are cells?

Answer 1

basic units of structure and organisation in organisms

Question 2

Function of ribosomes?

Answer 2

Protein synthesis (produce proteins)

Question 3

Function of SER?

Answer 3

Involved in detoxification, synthesises fats and steroids

Question 4

Function of RER?

Answer 4

Transports proteins to the Golgi Apparatus

Question 5

Function of mitochondrion?

Answer 5

Performs aerobic respiration in which glucose is broken down to release energy

Question 6

Function of golgi apparatus?

Answer 6

Modifies and repackages substances made by the ER, stores and packages substances in vesicles for secretion out of the cell

Question 7

Order of substance transport in cells?

Answer 7

Ribosomes -> RER -> Golgi apparatus -> Secretory vesicles

Question 8

What is differentiation?

Answer 8

Process by which a cell becomes specialised for a specific function

Question 9

Function of circular biconcave shape (red blood cell)?

Answer 9

Increases surface area to volume ratio for increased rate of oxygen uptake and increased rate of oxygen transport

Question 10

Absence of nucleus in red blood cell?

Answer 10

Allows packing of haemoglobin for increased rate of transport of oxygen

Question 11

Function of flexible cell surface membrane in red blood cell?

Answer 11

Allows cell to alter shape to easily squeeze through narrow capillaries for continuous increased rate of oxygen transport

Question 12

Function of haemoglobin?

Answer 12

Binds to oxygen and transports it around the body

Question 13

Function of mitochondria in muscle cell?

Answer 13

Releases more energy via respiration for contraction of the muscle cell

Question 14

Function of contractile protein fibres in muscle cell?

Answer 14

Contract and relax to bring about movement

Question 15

Function of elongated and cylindrical shape in muscle cell?

Answer 15

Allows for easy arrangement into parallel arrays which increases the strength of the muscles

Question 16

Purpose of many nuclei in muscle cell?

Answer 16

Allows for more synthesis and secretion of skeletal muscle proteins to support increased rate of muscle contraction + cell division for cell replacement

Question 17

Function of long, narrow protrusion in root hair cell?

Answer 17

Increases surface area to volume ratio to increase the rate of absorption of water molecules and mineral ions

Question 18

Purpose of lower water potential in cell sap?

Answer 18

Maintains a steep water potential gradient to allow water molecules to continuously enter the cell by osmosis

Question 19

Purpose of numerous mitochondria in root hair cell?

Answer 19

Release more energy via respiration to increase the rate of active transport for the absorption of mineral ions

Question 20

Function of uniformly thin cell wall

Answer 20

Reduces distance for diffusion to increase the rate of absorption of water molecules and mineral ions

Question 21

Define diffusion

Answer 21

The net movement of particles from a region of higher concentration to a region of lower concentration, down a concentration gradient

Question 22

Define concentration gradient

Answer 22

The difference in concentration between two regions

Question 23

The ____ the concentration gradient is, the ____ the rate of diffusion is

Answer 23

steeper, faster

Question 24

Define osmosis

Answer 24

The movement of water molecules across a partially permeable membrane, from a region of higher water potential to a region of lower water potential

Question 25

Factors affecting the rate of diffusion

Answer 25

Concentration gradient, diffusion distance, surface area to volume ratio

Question 26

Define water potential

Answer 26

The measure of the tendency of water molecules to move from one place to another

Question 27

Higher water potential indicates a more ____ solution

Answer 27

dilute

Question 28

Lower water potential indicates a more _____ solution

Answer 28

concentrated

Question 29

What happens when there is higher water potential in a plant cell?

Answer 29

The cell expands or swells, becomes turgid, cell contents press against the cell wall

Question 30

What happens when there is higher water potential in an animal cell?

Answer 30

The cell expands and bursts

Question 31

What happens when there is lower water potential in a plant cell?

Answer 31

The cell undergoes plasmolysis, becomes limp or flaccid

Question 32

What happens when there is lower water potential in an animal cell?

Answer 32

The cell shrinks and becomes crenated

Question 33

Explain plasmolysis

Answer 33

Process where the cytoplasm shrinks from the cell wall. Cell wall retains its shape

Question 34

What is turgor?

Answer 34

Turgor plays an important role in maintaining the shape of soft tissues in plants

Question 35

Diffusion and osmosis are _____ passive processes in that they do not require _____________

Answer 35

passive, respiratory energy

Question 36

Define active transport

Answer 36

The process in which energy is used to move the particles of a substance against a concentration gradient (From a region of lower concentration to a region of higher concentration)

Question 37

Active transport only occurs in _______________

Answer 37

Respiring living humans