Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

biology > excretion > Flashcards

excretion Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

define excretion

A

the process by which metabolic waste products and toxic substances are removed from the body of an organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

define anabolism, catabolism, and metabolism

A

anabolism:
* metabolic reactions where simple molecules are built up into complex molecules with a net intake of energy

catabolism
* metabolic reactions where complex molecules are broken down to simpler molecules with a net release of energy

metabolism
* sum total of all chemical reactions occuring in the cells of an organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

state at least 2 examples of anabolism and catabolism

A

anabolism:
* photosynthesis
* conversion of excess glucose to glycogen for storage

catabolism
* hydrolysis
* tissue respiration
* deamination of excess amino acids into urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why must metabolic waste products be removed?

A

these products are unwanted products from metabolic reactions and are harmful if allowed to accumulate in the body, therefore must be removed of desposited as harmless insoluble substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define egestion

A

removal of waste substances, mainly undigested matter, from the alimentary canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

contrast excretion and egestion

A

Egestion: removal of waste substances, mainly undigested matter, which have never been absorbed into cells and hence are not produced as a result of metabolic reactions within cells

Excretion: removal of waste substances that are produced by metabolic reactions that occur within cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

contrast excretion in unicellular and multicellular organisms

A
  • Unicellular: excrete metabolic waste products into surrounding water by diffusion
  • Multicellular: require special excretory organs to remove metabolic waste products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

identify 3 excretory organs in humans, and their respective excretory products

A
  1. Lungs: carbon dioxide, water vapour
  2. Kidneys: nitrogenous waste, excess mineral salts, excess water
  3. Skin: excess mineral salts, excess water, small amount of nitrogenous waste
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

state the 3 functions of healthy kidneys

A
  1. Removal of toxic metabolic waste
  2. Osmoregulation to maintain water potential of blood plasma
  3. Maintain pH and composition of blood plasma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

identify the 7 parts of the urinary system and state their functions

A
  • Hilum (not really a part): depression where renal artery, renal vein and nerves are connected to kidney
  • Kidney: remove urea and excess water from the blood as urine and maintains chemical concentrations in the blood
  • Ureter: tube that brings urine from each kidney to urinary bladder
  • Urinary bladder: elastic muscular bag that stores urine
  • Sphincter muscle: controls urine flow into the urethra and out of the body
  • Urethra: duct through which urine passes from urinary bladder to outside of body
  • Liver: produces urea through deamination of amino acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

contrast renal vein and renal arteries

A

Renal artery vs Renal vein

structural (callback to transport in humans)
* thicker more muscular and elastic walls
* valves absent vs valves present

blood composition
* higher concentration of oxygen vs lower ..
* higher concetration of urea vs lower ..
* lower concentration of carbon dioxide vs higher ..
* higher water potential vs lower ..

direction of blood flow
* from heart to kidney vs away from kidney to heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

state how to differentiate the cortex and medulla

A
  • Cortex: outer darker red region
  • Medulla: inner, thicker, paler red region
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

fill in the blanks

A

answer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

state the 4 parts of nephron in order and state the processes involved, and which useful substances are reabsorbed

A

1- proximal convoluted tubule
* active transport & diffusion –> ALL glucose, ALL amino acids, MOST mineral salts
* osmosis –> MOST of water

2- loop of Henle
* osmosis –> SOME water

3- distal convoluted tubule
* active transport & diffusion –> SOME mineral salts

4- collecting duct
* osmosis –> SOME water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

state the substances excreted into urine

A
  • EXCESS water
  • EXCESS mineral salts
  • nitrogenous waste products (e.g. urea, uric acid, creatinine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

state and describe the process that happens in the glomerulus

A

Ultrafiltration
* removes small molecules from the blood
* most of the blood plasma is forced out of glomerular blood capillaries into Bowman’s capsule to form the glomerular filtrate

17
Q

explain how the glomerulus is adapted to allow ultrafiltration

A
  1. afferent arteriole has a larger diameter than efferent arteriole, which creates a high hydrostatic pressure for ultrafiltration to occur
  2. basement membrane around glomerular blood capillaries has very small pores so that it is partially permeable and allows only water and very small molecules to pass through
18
Q

what is filtered off during ultrafiltration?
state 4 substances not filtered off

A

Filtered
1. water
2. mineral salts
3. glucose
4. amino acids
5. nitrogenous waste products

Not filtered
1. Blood cells
2. Platelets
3. Proteins (too large)
4. Fats (too large)

19
Q

how does selective reabsorption occur (briefly)

A

useful substances are selectively reabsorbed from the filtrate formed by ultrafiltration through the walls of the tubule into surrounding blood capillaries

20
Q

state at least 3 of 5 causes for kidney failure

A
  1. high blood pressure
  2. diabetes
  3. alcohol abuse
  4. damage to kindey(s) due to accident
  5. complications from major surgeries
21
Q

state at least 2 of 3 ways to treat kidney failure

A
  1. kidney transplant
  2. hemodialysis
  3. peritoneal dialysis
22
Q

state what occurs during hemodialysis

A
  1. blood is channeled from a vein of the patient’s arm to the dialyser of a dialysis machine
  2. blood flows into the tubing of dialyser, which is bathed in a specially controlled dialysis fluid .
  3. small molecules such as urea and other metabolic waste products diffuses out of tubing into dialysis fluid through the partially permeable walls of the tubing
  4. blood cells, platelets, and large molecules remain in the tubing
  5. filtered blood is then returned to the vein of the patients’s arm
23
Q

state features of the dialysis machine and how it aids it in its function

A
  1. tubing is long, narrow and coiled: increase SA:V for more efficient exchange of substances between blood and dialysis fluid
  2. dialysis fluid contains no metabolic waste products: SETS UP a steep concentration gradient for more efficient diffusion of metabolic waste products out of tubing into dialysis fluid
  3. dialysis fluid has same concentration of essential nutrients as healthy blood: ensures that there is no diffusion of essential nutrients out of blood into dialysis fluid, and essential nutrients can also diffuse from dialysis fluid into tubing should a patient’s blood lack these.
  4. direction of blood flow in tubing is opposite to flow of dialysis fluid: MAINTAINS a steep concentration gradient between patient’s blood and dialysis fluid for removal of metabolic waste products

“no metabolic waste products” should be replaced with no urea if question is specific
point 3 should not be written if question asks for removal of substances

24
Q

state features of dialysis fluid

A
  1. maintained at body temperature (to prevent blood from gaining or losing heat)
  2. sterile (free from pathogens + contaminants)
  3. contains glucose/amino acids at same conc. as healthy blood
  4. does not contain any urea

biology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions