Cell structure, Variety of Life, Levels of organisation.

Question 1

Define nutrition

Answer 1

ability to absorb nutrients for energy and cell growth and repair

Question 2

what is respiration

Answer 2

ability to produce energy from food molecules such as glucose

Question 3

what is excretion

Answer 3

removal of metabolic waste from the body

Question 4

what is sensitivity

Answer 4

the ability to detect change and respond to environment

Question 5

what is movement

Answer 5

ability to change location of part of the body

Question 6

what is homeostasis

Answer 6

ability to maintain a stable internal environment

Question 7

what is reproduction

Answer 7

ability to produce offspring

Question 8

what is growth

Answer 8

a permanent increase in size due to increase in cell number

Question 9

define prokaryotic

Answer 9

organisms that do not contain membrane bound organelles e.g. bacteria

Question 10

define eukaryotic

Answer 10

organisms containing membrane bound organelles e.g. animals, plants and fungi

Question 11

what is the role of the nucleus

Answer 11

controls cell activity and contains genetic material

Question 12

what is the role of the cell membrane

Answer 12

forms the outer surface of the cell and controls movement in and out of the cell

Question 13

what is the role of the cytoplasm

Answer 13

gel like substance that is the site of chemical reactions

Question 14

what is the role of ribosomes

Answer 14

site of protein synthesis

Question 15

what is the role of mitochondria

Answer 15

site of aerobic respiration

Question 15

what is the role of chloroplasts

Answer 15

site of photosynthesis

Question 16

what is the role of the cell wall

Answer 16

rigid structure that supports and strengthens the cell

Question 17

what is the role of the vacuole

Answer 17

large organelle that supports cell rigidity and structure

Question 18

what is a tissue

Answer 18

group of similar cells that work together to carry out a function

Question 19

what is an organ

Answer 19

a group of tissues that work together to carry out a function, they work together to form organ systems

Question 20

describe the structure of fungi

Answer 20

single celled, chitin cell wall, feed by saprotrophic nutrition, and store carbs as glycogen

Question 21

how do plants store carbs

Answer 21

sucrose or starch

Question 22

what is saprotrophic nutrition

Answer 22

secretion of extracellular enzymes into the area outside their body to dissolve food so they can absorb their nutrients

Question 23

describe the structure of protoctists

Answer 23

single celled organisms, some contain chloroplasts

Question 24

describe the structure of bacteria

Answer 24

single celled, no nucleus, circular chromosomes, feed of other organisms

Question 25

describe the structure of viruses

Answer 25

non living, smaller than bacteria, reproduce when on host cell, protein coat rapped around some genetic material, infect other organisms

Question 26

what is a catalyst

Answer 26

a substance that increases the rate of reaction without being used up

Question 27

describe the lock and key theory

Answer 27

active site and substrate join to form enzyme substrate complex, the products are then released, enzyme active site is very specific

Question 28

explain the effects of temperature and PH on an enzyme

Answer 28

if temperature is too high, then enzyme denatures and active site no longer able to join with substrate. if PH is too high or too low then enzyme denatures.

Question 29

how to measure the rate of reaction using the enzyme catalase on the breakdown of hydrogen peroxide into water and oxygen

Answer 29

use pipette to add a set amount of hydrogen peroxide to a boiling tube, set the temp. to 10 degrees, add catalase to the hydrogen peroxide and quickly attach the bung, record amount of oxygen produces in a minute, and repeat 3x, record for 20, 30, 40 degrees

Question 30

how to measure how fast the substrate disappears using the enzyme amylase to breakdown starch to maltose

Answer 30

use iodine solution, if starch is present, the solution will turn from brown orange to black

Question 31

what is diffusion and what substances are too big to pass across the cell membrane

Answer 31

the net movement of particles from an area of high concentration to an area of low concentration, large molecules such as starch and protein are unable to pass the membrane

Question 32

what is osmosis

Answer 32

the net movement of water molecules across a partially permeable membrane from an area of higher water concentration to region of lower water concentration. substances such as sucrose are unable to pass.

Question 33

how can you investigate diffusion in non-living systems

Answer 33

make agar jelly with phenolphthalein and dilute sodium hydroxide put some dilute hcl in a beaker, cut out a few cubes of the agar jelly and put them in the beaker with the acid, eventually the cubes will go colourless as the acid diffuses into the jelly and neutralises the sodium hydroxide.

Question 34

what happens to potato cylinders if - they draw in water - they draw out water

Answer 34

in-get longer out-shrunk

Question 35

what is active transport

Answer 35

the active movement of particles against the concentration gradient from an area of low concentration to an area of high concentration using energy from respiration