practicals

Question 1

describe the test for starch

Answer 1

-add a few drops of iodine to the substance
-if it contains starch it will change from orange to blue-black

Question 2

describe the test for lipids

Answer 2

-add ethanol to the substance
-leave it for one minute
-it will turn from colourless to cloudy

Question 3

describe the test for proteins

Answer 3

-add copper sulfate solution
-changes from pale blue to purple

Question 4

what is the test for glucose?

Answer 4

-add a few drops of Benedicts solution
-colour change from blue to orange-red

Question 5

what are the two types of sampling? describe them

Answer 5

-non-random sampling - samples are taken at predetermined points
-random sampling - samples are taken at random

Question 6

what breaks down starch

Answer 6

amylase breaks down starch into glucose

Question 7

what breaks down protein

Answer 7

protease breaks down proteins into amino acids

Question 8

what breaks down fats?

Answer 8

lipase breaks down fats into fatty acids and glycerol

Question 9

describe two ways to take the rate of photosynthesis

Answer 9

-count the number of oxygen bubbles
-measure the time taken to produce a fixed amount of gas

Question 10

how can you identify which bacteria you have in a culture

Answer 10

-overall size and shape
-the texture of its edges and surfaces
-elevation above the agar
-transparency and colout

Question 11

how do you measure the zone of inhibition

Answer 11

the area that is clear of any bacterial growth around a point

Question 12

what is the acronym for mitosis?

Answer 12

IPMAT

Question 13

describe interphase

Answer 13

the DNA in the cell doubles

Question 14

describe prophase

Answer 14

the DNA forms x-shaped chromosomes

Question 15

describe metaphase

Answer 15

the chromosomes line up at the centre of the cell and cell fibres pull them apart. the two arms of each chromosome go to opposite ends of the cell

Question 16

describe anaphase

Answer 16

membranes form around each of the sets of chromosomes. these become the nuclei of the two new cells

Question 17

what is telophase

Answer 17

the cytoplasm divides

Question 18

describe the stages of interphase

Answer 18

-gap phase
-synthesis
-gap phase 1
-mitosis

Question 19

describe gap phase 1

Answer 19

cell grows and new cell structures and proteins are made

Question 20

describe synthesis in the cell cycle

Answer 20

the cell replicates its DNA

Question 21

describe gap phase 2

Answer 21

cell keeps growing and proteins needed for cell division are made

Question 22

what is the outer layer of the kidney called?

Answer 22

the cortex

Question 23

what is the inner layer of the kidney called?

Answer 23

the medulla

Question 24

what is the function of the ureter and where it is located?

Answer 24

-carries urine from the kidneys to the bladder
-in the kidney, it is in the middle

Question 25

where are the nephrons located?

Answer 25

they start in the cortex, loop down into the medulla and back to the cortex

Question 26

describe the bowman’s capsule

Answer 26

surrounds a ball of capillaries called the capillary knot

Question 27

describe ultrafiltration

Answer 27

-high pressure is created in the capillary knot by the diameter of the capillary leaving the knot being narrower than the capillary entering
-ultrafiltration - small molecules pass out of the capillary and into the bowman’s capsule (waste products)
-proteins and blood cells are too big to leave the capillaries to go into the tubule