Physiology

Question 1

levels of organisation in the body

Answer 1

cells, tissue, organ, organ system, body

Question 2

how many pairs of chromosomes in a normal cell and what is the last pair

Answer 2

23 pairs last pair is sex chromosomes either xx or xy

Question 3

what is karyographs

Answer 3

seeing chromosomes for gender or if they are missing any or have too many.

it is done by amniocentesis(needle of amniotic fluid) then centrifuged and micro scoped

Question 4

what trisinamy 21 and features

Answer 4

extra chromosome (downsyndrome) of 21st chromosome

single horizontal palm crease
flattened facial features
macroglossia( big tongue)
hole in septum of heart

Question 5

features of trisynamy 13

Answer 5

cleft pallet
missing eye
incomplete brain development

Question 6

different and their jobs

Answer 6

nucleus- holds DNA
SER- lipid production
RER- protien production
Ribosomes- Protien synthesis
Golgi- packages proteins and lysosomes
vecicles- transport vessels
Mitochondria- respiration
plasma membrane- partially permiable

Question 7

features of plasma membrane

Answer 7

phospholipid bilayer
cholestrol thats glue
protien channels
receptors for cell signalling
transmembrane protiens

Question 8

what is simple diffusion

Answer 8

diffusion from high to low across semi permiable membrane

Question 9

facilitated diffussion

Answer 9

diffusion from high to low across a membrane aided by a carrier

Question 10

what is osmosis

Answer 10

movmenet of water scross a semi permeable membrane from high to low water potentisal

Question 11

what is isotonic hyper and hypotonic

Answer 11

isotonic same concentration

hypertonic-greater concentration dehydration- cells are hypertonic of water so the water moves out

hypotonic- lesser concentration
water intoxication cells are hypotonic of water so water moves in

Question 12

what is homeostasis

Answer 12

bodies ability to remain relitvley stable

Question 13

what is negative feedback and examples

Answer 13

when body moves out of normal range response is stopped to bring it back to normal eg blood glucose and heart rate

Question 14

requirments for negative feedback

Answer 14

stimulus> sensor to detect stimulus> control centre to decide what to do> effector(response)

Question 15

sodium homepstasis

Answer 15

aldosterone is released when sodium falls bellow normal value hypotraenimea which promotes reabsorbtion to kidneys

hypertraenemia- aldosterone stops

Question 16

potassium homeostasis

Answer 16

aldosterone is released when potassium levels are too high hyperkaelimia and the kidneys eliminate it

hypokaelemia- aldosterone is inhibited

Question 17

what is positive feedback- example

Answer 17

deviation from norm is amplified eg oxytocin in childbirth

Question 18

parts of the kidney system

Answer 18

kidney- produces urine
ureter- carries urine away
urinary bladder- holds urine
urethra- allows urine to leave bladder

Question 19

kidney anatomy

Answer 19

hillium- indentation in kidney for renal nerves and veins

kidney pelvis- urines way out

cortex- outer part
medulla inner part

nephron- site of filtration

Question 19

composition of urine

Answer 19

95% water 5% toxins and nitrogenous waste like urea

Question 19

kidneys function

Answer 19

excretion, filter blood, remove excess water ions and urea, involved in blood homeostasis

produce epo which synthesises erythrocytes

produce renin which increases blood pressure, allows vasoconstriction

Question 20

nephron anatomy

Answer 20

glomeroulus>pct>loop of henle>Dct

Question 21

stages of urine formation

Answer 21

glomerular filteration- small molecules like water are filtered

tubular reabsorbtion- water is retained in pct lh and dct

secretion- ammonium excess water and ions can be actively secreted into urine.