chapter 1 - cell structure and transport

Question 1

what kind of cell is eukaryotic?

Answer 1

animal and plant cells

Question 2

what kind of cell is prokaryotic?

Answer 2

bacteria cells

Question 3

what is found in the nucleus of animal and plant cells?

Answer 3

DNA

Question 4

function of cell membrane?

Answer 4

to control movement of substances in and out of the cell

Question 5

function of mitochondria?

Answer 5

the site of respiration to transfer energy to the cell

Question 6

function of chloroplasts?

Answer 6

contain chlorophyll to absorb light energy for photosynthesis

Question 7

function of cell wall?

Answer 7

strengthens and supports the cell

Question 8

structure of main genetic material in prokaryotic cell?

Answer 8

a single loop of DNA

Question 9

electron microscopes VS light microscopes?

Answer 9

electron microscopes:

• use beams of electrons instead of light
• cannot be used to view living samples
• are much more expensive
• have a much higher magnification and resolution

Question 10

function of red blood cell?

Answer 10

to carry oxygen around the body

Question 11

adaptations of red blood cell?

Answer 11

• no nucleus to make extra space for haemoglobin
• contains a red pigment called haemoglobin
• they have a bi-concave disc shape

Question 12

function of nerve cell?

Answer 12

to carry electrical impulses around the body

Question 13

function of sperm cell?

Answer 13

to fertilise an ovum (egg)

Question 14

adaptations of sperm cell?

Answer 14

• a tail to help them swim

- lots of mitochondria to release energy for swimming

Question 15

function of palisade cell?

Answer 15

to carry out photosynthesis in a leaf

Question 16

adaptations of palisade cell?

Answer 16

• have lots of chloroplasts for photosynthesis

- are located at the top surface of the leaf to absorb maximum light energy

Question 17

function of root hair cell?

Answer 17

to absorb minerals and water from the soil

Question 18

adaptations of root hair cell?

Answer 18

• large surface area to increase the rate of diffusion and osmosis
• lots of mitochondria to release energy for active transport

Question 19

what is diffusion?

Answer 19

the net movement of particles from an area of high concentration to an area of low concentration down a concentration gradient
> a passive process, doesn’t require energy from respiration

Question 20

factors that affect the rate of diffusion?

Answer 20

• concentration gradient
• temperature
• membrane surface area

Question 21

how are villi adapted for exchanging substances?

Answer 21

• a long, thin shape - increases surface area
• a one-cell-thick membrane - short diffusion pathway
• a good blood supply - maintains a steep concentration gradient

Question 22

how are lungs adapted for efficient gas exchange?

Answer 22

• alveoli - large surface area
• moist membranes - increases rate of diffusion
• one-cell-thick membranes - short diffusion pathway
• good blood supply - maintains a steep concentration gradient

Question 23

how are fish gills adapted for efficient gas exchange?

Answer 23

• large surface area for gases to diffuse across
• thin layer of cells - short diffusion pathway
• good blood supply - maintains a steep concentration gradient

Question 24

what is osmosis?

Answer 24

the diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane

Question 25

example of osmosis in a plant?

Answer 25

water moves from the soil into the root hair cell

Question 26

what is active transport?

Answer 26

the movement of particles against a concentration gradient - from a dilute solution to a more concentrated solution - using energy from respiration

Question 27

why is active transport needed in plant roots?

Answer 27

the concentration of mineral ions in the soil is lower than inside the root hair cells - the mineral ions must move against the concentration gradient to enter the root hair cells

Question 28

purpose of active transport in the small intestine?

Answer 28

sugars can be absorbed when the concentration of sugar in the small intestine in lower than the concentration of sugar in the blood

Question 29

where is diffusion important?

Answer 29

• lungs: need to get oxygen into blood
• kidneys: waste urea dissolves into blood
• small intestine: need to get to nutrients
• roots: minerals into plant

Question 30

what is concentration?

Answer 30

number of particles in a set volume

Question 31

what is the concentration gradient?

Answer 31

difference in concentration

Question 32

characteristics of eukaryotic?

Answer 32

• cell membrane
• cytoplasm
• genetic material (DNA) -> in nucleus

Question 33

characteristics of prokaryotic?

Answer 33

• smaller than eukaryotic
• genetic material isnt in nucleus
• DNA is a single loop
• (one or more rings of DNA is called plasmids)

Question 34

the equation linking magnification, image and actual size?

Answer 34

M = I/A 
magnification = image / actual size

Question 35

define resolution?

Answer 35

the shortest distance between two objects that can be seen clearly

Question 36

what is hypertonic?

Answer 36

more concentrated solution than in cells

Question 37

what is isotonic?

Answer 37

same concentration with solution and cells

Question 38

what is hypotonic?

Answer 38

more dilute than solution in cells