Chapter 31: Excretion Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Describe plant excretion.

A

Give off little waste
Store some and lose most waste when dead structures fall off
Lose waste gases through stomata and lenticels

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

What are the three layers of skin?

A

Epidermis
Dermis
Adipose tissue/subcutaneous tissue

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

There are 3 layers within the epidermis what are they?

A

Cornfield layer
Granular layer
Malpighian layer

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

Describe the cornfield layer.

A

Keratin build up causes the cell to become hardened
Lack of blood capillaries
This causes the Cells to die and flake off

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

Describe the granular layer.

A

Cells push through this layer and make protein called keratin

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

Describe the malpighian layer.

A

New cells are made here by mitosis.

Specialized cells make melanin which gives the skin colour and protects against us rays

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

Describe the dermis.

A

Made of connective tissue with the protein collagen for strength.
Contains sweat glands, hair follicles, blood vessels, nerve receptors, sebaceous glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are sebaceous glands?

A

They produce oil called sebum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is adipose tissue?

A

Fat acts as a food store

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens to skin in cold conditions?

A

Erector muscle contracts to form goose bumps
Causes hair to stand up in a reaction called pilorection
A layer of warm air is trapped between the hairs.
Blood vessels contract which reduces heat loss - vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What muscle forms goose bump?

A

Erector muscle

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

What process causes hairs to stand up?

A

Pilorection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What process causes blood vessels to contract?

A

Vasoconstriction

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

What happens to skin in warm conditions?

A

Sweat produced by sweat glands - evaporation of water lowers body temp
Blood vessels dilate - increase heat loss through skin

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

What are 5 other functions of skin?

A
Protection 
Vitamin production 
Food store
Sense organ 
Excretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Give 4 examples of how skin protects us.

A

Epidermis - water loss and entry of pathogens
Dermis - protects internal organs
Melanin - from uv rays
Sebum - prevents skin from drying up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What vitamin is made in skin?

A

Vitamin d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is excretion?

A

Removal of waste products of metabolism from the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is egestion?

A

Removal of undigested unabsorbed material from the digestive system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 4 roles of the excretory system in homeostasis?

A
  1. Regulates body temp
  2. Osmoregulation
  3. Controls concentration of fluids
  4. Removes waste
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the three organs of excretion and the waste products they make?

A

Lungs - water and carbon dioxide
Skin - water and salt
Kidneys - water salt and urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is urea made from and where?

A

Liver - deamination of amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is Uric acid made from and where?

A

Liver - breakdown of nucleic acid

24
Q

Where does water and co2 come from?

A

Cellular respiration

25
Q

What does the renal artery do?

A

Brings bloods with wastes from all over the body to the kidneys

26
Q

What are the 3 main processes of the kidneys?

A

Filtration - filters blood, outer cortex
Reabsorption - useful substances reabsorbed, modulla + cortex
Secretion - substances are secreted from the blood into the cortex of the kidneys, substances such as potassium (k) and hydrogen ions

27
Q

What is urine made from?

A

96% water

  1. 5% nitrogenous wastes
  2. 5% salts
28
Q

What does the renal vein do?

A

Brings purified blood back to the body

29
Q

What does the renal pelvis do?

A

Gathers Urine from medulla

Sends urine down ureter

30
Q

What is the function of the bladder?

A

Involuntary muscular organ that forces urine out into the urethra
Has two sphincter muscles that contract to allow urine to pass out

31
Q

What are the 4 functions of the kidneys?

A

Excretion - remove waste
Osmoregulation - vary water content of urine
Salt concentration - vary amount of salt relished in the urine
Ph control - produces urine that is either basic or acid to maintain body ph at 7.4 (hydrogen ion)

32
Q

What is the nephron?

A

The functional unit of the kidney - makes urine

33
Q

How many nephrons are in a kidney?

A

1 million +

34
Q

Describe the blood supply of the nephron.

A

Aorta - renal artery - renal arterioles - afferent arterioles - glomerulus - efferent arterioles - capillaries (becomes deoxygenated here) - renal venule - renal veins - vena cava

35
Q

What are the 3 processes involved in the nephron?

A

Same as kidneys
Filtration
Reabsorption
Secretion

36
Q

What does filtration mean?

A

Water and small molecules pass from blood to nephron

37
Q

What is reabsorption?

A

Molecules passes from the nephron back into the blood

38
Q

What is active transport?

A

Means that energy is used to move molecules from place of low concentration to high concentration

39
Q

What part of the nephron does filtration occur?

A

Glomerulus filters molecules out of plasma into the bowmans capsule

40
Q

What materials are filtered into the bowmans capsule?

A

Glucose, amino acids, vitamins, hormones, urea, salt, water

41
Q

What materials cannot be filtered into the bowmans capsule?

A

Red blood cells, white blood cells, platelets, antibodies, clotting proteins, some hormones

42
Q

Where does blood enter the nephron?

A

Afferent arterioles

43
Q

What is the substance in the bowmans capsule known as?

A

Glomerular filtrate

44
Q

What are the 3 ways the glomerulus helps filtration?

A
  1. Pressure is greater: efferent arterioles is narrower meaning that blood must be put under more pressure to enter it
  2. Large surface area in capillaries
  3. Walls of capillaries are more porous than normal
45
Q

How much of the glomerular filtrate is reabsorbed?

A

99%

46
Q

Explain what happens in the proximal convoluted tubule.

A

Proximal convoluted tubule is one cell thick, many infoldings (microvilli) and mitochondria
Water is reabsorbed here by osmosis
Salt, glucose, vitamins, amino acid are reabsorbed by diffusion

47
Q

What structures reabsorb water?

A

Proximal convoluted tubule
Descending loop of henle
Distal convoluted tubule
Collecting duct

48
Q

Apart from water what does the distal convoluted tubule controls?

A

Salt, ph

49
Q

What does the ascending loop of henle control?

A

Moves salt into medulla using diffusion, uses active transport at the top of medulla

50
Q

Where is most water reabsorbed?

A

Proximal convoluted tubule

51
Q

What is secretion?

A

Movement of material from blood to nephron

52
Q

What is secreted in the distal convoluted tubule?

A

Potassium and hydrogen ions

53
Q

What is the difference between glomerular filtrate and urine?

A

Urine does not have glucose, amino acids but glomerular filtrate does

54
Q

What happens when there is a lack of water in plasma?

A

Brian detects it
Pituitary gland releases adh
Adh travels to kidney
Adh causes the distal tubule to become more permeable to water
More water is reabsorbed from nephron into plasma
Lowers the volume of urine produced

55
Q

What happens when there is too much water in plasma?

A

Brain detects it
Pituitary gland releases adh
Walls of distal tubule become more impermeable to water
Water not reabsorbed from nephron into plasma
Increases the volume of urine produced

56
Q

How does blood become too concentrated?

A

Drink too little water
Consume too much salt
Lose too much water as sweat

57
Q

How does blood become too dilute?

A

Consume too much water

Eat too little salt