Important- focus

Question 1

In a vascular bundle what does the xylem look like

Answer 1

the larger cells

Question 2

How does ADH affect low water levels in the body?

along with the help of renin from kidney cells

Answer 2

when there is low water levels in the body- ADH is secreted from the hypotalamus, and makes the kidney neprhons more permable/ increases the presence of aquaphorins. It also stimulates the thirst centre, so more water is reabsorbed, and more water is consumed. more sodium is also readbsorbed.

Question 3

how does ADH affect high water levels in the body

Answer 3

ADH suppresess the thirst centre, and supresses sodium reabsorbtion, which decreases water consumption and reabsorbtion

Question 4

what is the diffrence between type 1 and 2 diabetes

Answer 4

in type 1 diabetes, the pancreas does not make insulin because the body destroys the beta cells which make insulin

where in type 2 diabetes the body makes less insulin and the body eventually becomes resistant

both types of diabetes affect insulin production and action in the body

Question 5

What happens as a result of diabetes?

Answer 5

too much glucose and sugar are in the bloodstream

Question 6

what can type 1 diabetes lead to the development of?

Answer 6

hyperglycaemia or hypoglycaemia

Question 7

what is hyperglycaemia?

Answer 7

the state of having high blood glucose levels

Question 8

what is hypoglycaemia

Answer 8

occurs when blood sugar levels drop- can occur if too much insulin is injected or not enough glucose is consumed

Question 9

What are the symptoms of hyperglycaemia

Answer 9

increased thirst
frequent need to urinate
tiredness
blurred vision
unintentional weight loss
dry skin and mouth
rapid breating
neasia, vomiting
rapid pulse
confusion

Question 10

what are the symptoms of hypoglycaemia

Answer 10

sweating
pale
irratibility
hunger
lack of coordination
sleepiness

Question 11

What is hyperthyroidism

Answer 11

Condition caused by an overactive thyroid gland, resulting in increased amounts of thyroid hormone secretion, causing a wide range of symptoms.

the thyroid secrets T4 and T3 which travel to cells all around the body to regulate many metabolic processes. when too much of these hormones are released, the speed of the bodys metabolism increases and can lead to health issues.

Question 12

what are linked genes?

Answer 12

genes that are closer together on a chromosome, so they are more likely to be inherited together, and to not be seperated during crossing over

Question 13

what is the ratio for linked genes?

Answer 13

46% 4% 4% 46%

Question 14

what is the ratio for unlinked genes?

Answer 14

9:3:3:1

Question 15

what is a dihybrid cross?

Answer 15

a cross between 2 pairs of alleles

Question 16

what is a companion cell and what does it do?

Answer 16

next to seive cells- contain many mitochondria to supply the phloem with energy to transport sugars

Question 17

what does a seive cell do in the phloem?

Answer 17

help channel and transport sugars ans sap

Question 18

why is the xylem dead?

Answer 18

because they lack organelles

Question 19

where is the G1 checkpoint located and what does it do?

Answer 19

located after the G1 stage- vertifies if the cell has grown to the correct size

has synthesised enough for protiens for DNA replication

if the cell is damadged

if there is enough ogygen and nutrients

Question 20

where is the g2 checkpoint and what does it do

Answer 20

located after the g2 phase

vertifies if the DNA has replicated correctly in the S phase

the cell has enough recources for mitosis

Question 21

where is the M checkpoint and what does it do?

Answer 21

located after metaphase
vertifies if the formation of spindle fibers is correct

if the chromosomes are correctly lined up