Excretion Flashcards
What is homeostasis?
Keeping the conditions in the internal environment of the body relatively constant.
What is osmoregulation?
Maintenance of water and salt contents of the internal environment.
What is internal environment?
The inside of the body
What is tissue fluid?
Watery solution of salt, glucose and other solutes
How is the tissue fluid formed?
It is formed by the leakage from blood capillaries
Why is homeostasis important?
It is important because cells with only function properly if they are bathed in a tissue fluid which provide them with their optimum conditions.
Why is removing excretory products important?
Because they are toxic to cells.
What are some examples of nitrogenous waste?
Urea and ammonia
Select substances that can be stored.
(Carbohydrates, Fats, Proteins)
Carbohydrates, Fats
How much urine does an adult human produce?
1.5 dm^3
What does volume of urine produce in a day depend on?
It depends on amount of water drunk and volume loses in other form such as sweat.
What happened to protein as they cannot be stored?
They are converted into carbohydrate and main nitrogen containing waste product urea by the liver.
Is urea metabolic waste?
Yes
Why does urea passes into the blood?
They passed into the blood to be filtered out by the kidneys during the formation of urea.
Why faeces are not the metabolic waste?
Because they contain a few products of metabolisms, and only the remains of undigested food along with bacteria and dead cell
Does kidney carry out both homeostatic and excretion?
Yes
Oxygenated blood enter kidney through —–.
Renal artery
The blood entering the kidney is high pressure.
True
Deoxygenated blood leaves the kidneys through —–.
renal vein
Urine leaves the kidneys through —–.
ureters
What does the wall of urethra contain?
Sphincter muscles
Where does urine store?
Bladder
What does sphincter muscle have?
The upper sphincter muscle is involuntary so, it can’t be controlled.
The lower sphincter muscle is voluntary so, it can be controlled.
What does cortex contain?
Cortex contain many blood vessels branches from the renal artery and nephrons.
Which carry the urine from kidneys to the bladder?
The pelvis is connected with the ureter, carrying the urine to the bladder.
Where in the nephron is blood filtered?
Blood filtered and enter the capsule passing cells of capillary wall, basement membrane and cells of Bowman’s capsule.
What separated the blood in the glomerulus and bowman’s capsule?
Capillary walls and wall of capsule where there is basement membrane which is fine molecular filter between them.
What is glomerular filtrate?
The fluid that entered the capsule space is called glomerular filtrate.
What is ultrafiltration?
The process where the filter separate different sized molecules under pressure is called ultrafiltration.
How much glomerular filtrate does kidney produce per minute and per day and how much is secreted from body every day?
Kidney produces 0.125 dm^3 of glomerular filtrate and 180 dm^3 per day but only 1.5 dm^3 of urine is secreted from body per day.
What are the names of blood in and blood out of the glomerulus?
Blood in - Afferent
Blood out - Efferent
What substances are filter and not filtered during ultrafiltration or urine?
Substances that are filtered - glucose, urea, water and ions
Substances that are unfiltered - Protein, blood cells
What happened to flow rate, glucose, protein, urea and Na+ at blood plasma, glomerular filtrate, end of first coiled tube and collecting duct?
In the blood plasma
protein - contain
glucose - contain
urea - contain
Na+ - contain
In the glomerular filtrate
flow rate - 100%
protein - not contain
glucose - contain
urea - contain
Na + - contain
In the first coiled tube
flow rate - 20%
protein - not contain
glucose - not contain
urea - contain x 3
Na+ - contain
In the collecting duct
flow rate - 1%
Protein - not contain
glucose - not contain
urea - contain x 60
Na+ - contain x 2
Why the urea become more as it pass rest of the nephron?
As more water reabsorbed as it passes through the nephron, the urine become more concentrated with urea.
What is selective reabsorption?
Selective reabsorption is the process of reabsorbing different amounts of various substances.
What is the function of loop of Henlé?
It concentrates the fluid in the tubule by reabsorbing more water into the blood.
Which kind of loop of Henlé do desert animals, animals which have easy access to water and humans contain?
Desert animals have long loops of Henlé, animals which have easy access to water has short loops of Henlé and humans contain mixture of long and short loops.
What can long loop of Henlé make?
Long loop of Henlé can make more concentrated urine, conserving water in the bodies.
When you drink a lot of water, how will it affect urine content?
- Blood concentration decreased
- Which is detected by the hypothalamus
- Stimulate the pituitary produce less ADH
- Less ADH causes collecting duct to become less permeable to water
- Less water is reabsorbed
- More urine is excreted (urine concentration decrease)
In a hot summer day, you have sweat a lot, how will it affect urine?
- The blood concentration increase
- Which is detected by hypothalamus
- Stimulate pituitary produce more ADH
- More ADH result collecting duct to become more permeable to water
- More water is reabsorbed
- Less urine is excreted (Urine concentration increase)
Difference between cold blood and warm blood?
Cold blood animals body temperature changed depending on the environment unlike the warm blood animals which have constant pressure have ability to travel anywhere.
What is other names of warm and cold blooded animals?
Homeothermic - warm blooded (endotherms)
Poikilothermic - cold blooded
What do both warm and cold blood animals do to adapt the environment?
Depending on the environment, their behavior change.
What is the main difference between cold and warm blooded animals?
warm blood animals can keep their body temperature using physiological change.
What monitor the change in body temperature in mammals?
Thermoregulatory center in the hypothalamus
What are the functions of human skin?
- Forming tough outer layer which resist mechanical damage
- Forming impermeable membrane preventing water loss
- Acting as sensor for touch and temperature change
- Controlling the heat loss through body surface
- Acting as barrier for pathogen to enter
What is epidermis consist of?
Epidermis consist of dead cells which stops water loss and protect body against invasion of microorganism.
What does hypodermis contain?
Hypodermis contain fat tissues which insulate the body against heat loss and store of energy.
What does dermis layer contain?
Dermis layer contain many sensory receptors, sweat glands, small blood vessels and hair follicles.
What does sweat glands do in hot condition?
In hot conditions
- More sweat is produced
- Sweat only have cooling effects it evaporates using heat energy from body.
What does hair erecter muscle do in cold condition?
In cold conditions
- Hair erecter muscles contract
- Causing hairs to pulled upright
- Trapping a layer of air (poor conductor of heat) next to the skin
- Less heat is lost
But in warm conditions there will be thinner layers of trapped air meaning more heat will be lost.
What happens to blood vessels at hot and cold conditions?
In hot condition vasodilation occurs
- arterioles leading to capillary loop dilate
- increasing the blood flow to the skin’s surface
- As more blood flow through these loops, more heat is radiated
- Cooling the body down
In cold conditions vasoconstrictions occurs
- arterioles leading to capillaries loops constrict
- decreasing the blood flow to the skin’s surface
- As less blood flow through these loops, less heat is radiated
- Reducing heat loss through surface of the body
What does hormone adrenaline stimulate in cold condition?
They stimulate the increase in metabolism, generating heat.
What is shivering?
Shivering occurs where the muscles contract and relax rapidly.
What are some change in body that take place to keep temperature?
- Sweating
- vasodilation
- vasoconstriction,
- hair erections
- shivering
- changes in metabolisms and some behavioral change
keep the body temperature.
Can amino acids be stored?
No
Which break down the amino acids?
Liver
