Jan 2023 2Br

Question 1

How to find magnification

Answer 1

Convert into mm
Times with actual length

Question 2

why reducing leaf temperature reduces transpiration rate

Answer 2

• lower temp lower KE
  -water molecules moves less
• less diffusion

Question 3

Describe how water is transported from the soil to the leaves in plants.

Answer 3

• water enter thru root hair cells by osmosis
• dilute conc against more conc
  -water moves up to xylem
• transpiration pull
• due to water loss from stomata

Question 4

Why protein is present in urine

Answer 4

• ultrafiltration
• from glomerulus to into bowman’s capsule (high pressure)
• Protein passes through nephron

Question 5

Why glucose is present in urine

Answer 5

• Selective reabsorption
• in convoluted tube
• too much glucose in blood
• glucose not reabsorb in blood

Question 6

Why conc of water is high in urine

Answer 6

• reabsorption of water
• Less water reabsorb
• in the collecting duct

Question 7

Test for glucose

Answer 7

• Add benedict
• and heat

Question 8

Describe how the scientists could determine the number of each plant species
per m2
in each field.

Answer 8

• place quadrat
• randomly / random coordinate
• count number of each species in quadrat
• divide amount by area of quadrats

Question 9

Genome meaning

Answer 9

• All of DNA in an organism

Question 10

Roles of RNA in protein synthesis

Answer 10

• Transcription produces mRNA
• mRNA copies code of DNA strand
• moves out nucles and into cytoplasm
• bind with ribosomes
• tRNA brings amino acids to ribosome
• anticodon binds with codon
• translation produce polypeptide

Question 11

Transcription

Answer 11

• Two strands DNA unzip revealing amino acid
• RNA moves along and does complementary base pairing
• this creates mRNA
• mRNA leaves nucleus
• mRNA binds with ribosome in cytoplasm

Question 12

Translation

Answer 12

• mRNA binds with ribosome in cytoplasm
• tRNA’s anticodon does complementary base pairing with mRNA’s codon
• amino acids on
  neighbouring tRNA joins tgt
• forming chain of amino acids
• this is polypeptide

Question 13

Function of uterus

Answer 13

• implantation of embryo
• placenta grow
• provide nutriton

Question 14

FSH function

Answer 14

• cause egg to mature in follicle
  -Stimulates oestrogen

Question 15

LH function

Answer 15

• stimulate release of an egg at day 14

Question 16

Oestrogen function

Answer 16

• lining of eturus grow
• stimulates release of LH

Question 17

Progesterone

Answer 17

-maintains lining of uterus during second half of cycle
- progesterone falls = lining breaks down
- inhibits release of LH and FSH

Question 18

small fragments of plants which are regrown into whole
plants (micropropagation)

Answer 18

Explants

Question 19

source of energy in agar micropropagation

Answer 19

Glucose

Question 20

micropropagation produce large quantities of genetically identical plants called

Answer 20

Clone

Question 21

One advantage is that micropropagation is quicker than

Answer 21

Sexual

Question 22

micropropagation is that plants can be produced …………………………………………………….. the year.

Answer 22

Throughout the year