The Excretory system Flashcards
Information included in this deck: - 3.6 The Excretory System (textbook) - 3.6 The excretory system (slides, extra resource) -
1
Q
All the biochemical reactions carried out by a living thing are called _____
A
Metabolism
2
Q
How quickly metabolism occurs is called _____
A
Metabolic rate
3
Q
Each biochemical reaction that is part of a cell’s metabolism is called ____
A
A metabolic reaction
4
Q
The vital process of life made possible by metabolic reactions are called _____ ____.
e.g. aerobic ____ and _____
A
Metabolic processes
aerobic respiration and photosynthesis
5
Q
What are the harmful substances produced by metabolic reactions in cells that need to be removed?
A
Metabolic wastes.
6
Q
What is the removal of the wastes of metabolism called?
A
Excretion.
7
Q
Name some of the wastes that are excreted.
A
Carbon dioxide and nitrogen containing waste; for example urea.
8
Q
Is faeces a metabolic waste? If so or if not, why?
A
Faeces is not a metabolic waste because it is not produced by metabolic reactions - it is mostly indigestible food material
9
Q
The term excretion also refers to the removal of excess what?
A
Water and salts absorbed from the alimentary canal into the bloodstream, as well as removal of the breakdown products of hormones and drugs
10
Q
The excretory system is responsible for the removal of most ______ like ____
A
Nitrogen-containing waste lie urea
11
Q
The excretory system is located in the region of the body below the ____ called the ____
A
diaphragm called the abdominal cavity
12
Q
Through which artery does the blood flow into the kidney?
A
The renal artery
13
Q
Which vein does the blood that has passed through the kidney flow out of?
A
The renal vein
14
Q
Name the major organs of the urinary system
A
Kidney
Ureter
Bladder
Urethra
15
Q
Kidney
A
Produces urine to remove nitrogen-containing waste - maintains the balance of water and salts in the blood
16
Q
Ureter
A
Transports urine from the kidney to the bladder
17
Q
Bladder
A
Stores urine
18
Q
Urethra
A
Transports urine out of the bladder during urination
19
Q
Kidney tissue is packed with tiny ___ tubules that are a type of tube-like ___ tissue.
A
Renal tubules, epithelial
20
Q
Renal tubules have ___ associated with them and are held in place by _____
A
Blood vessels, connective tissue
21
Q
There are two distinct regions of the kidney tissue.
The outer region is called the ____.
The inner region is called the ____.
A
Cortex
Medulla
22
Q
What the is the structure called between the medulla and the top of the ureter?
A
The pelvis
23
Q
What is the structure that permits nitrogen-containing waste to be removed by the kidneys
A
A nephron
24
Q
Each nephron consists of a ____ tubule and a cluster of _____ located in the cortex called _____.
A
Renal tubule, capillaries, glomerulus
25
Where is the glomerulus loacted?
In the cup-like structure of the nephron called Bowman's capsule
26
Blood is transported into a kidney passes from a branch of the _____ under ____ pressure to the ___ where it undergoes a process called _____
Renal artery, glomerulus, filtration
27
Filtration causes __ and other small materials too __ the blood and enter the ____
Provide examples
Water, leave, Bowman's capsule.
e.g. glucose, amino acids, salts and nitrogen-containing waste urea.
28
The larger components ___ and ___ are not filtered and remain in the blood.
Blood cells and plasma proteins
29
What is the fluid that passes into the bowman's capsule?
Glomerular filtrate
30
The filtered blood moves through ___ that surround the ____, ____ and ____
Capillaries, proximal tubule, the loop of henle and the distal tubule
31
What is the process of some filtered materials being returned to the bloodstream called?
Provide examples?
Reabsorption
e.g. reabsorption of water, glucose and amino acids at the proximal tubule
32
Nitrogen-containing waste is or isn't reabsorbed?
It is not reabsorbed.
33
Blood then passes where for transport out of the kidney?
To a branch of the renal vein.
34
Define the structure and function of the Glomerulus
Structure: A cluster of semi-permeable capillaries
Function: Blood pressure high enough for filtration. Blood cells and large blood proteins are not filtered.
35
Define the structure and function of the Bowman's capsule
Structure: Cup-shaped and hollow
Function: Surrounds the glomerulus to collect water and other substances that leave the blood by filtration
36
Define the structure and function of the proximal tubule
Structure: Tube-like, walls lined with micro-villi, walls very thin and moist, Surrounds capillaries
Function: Allows glomerular filtrate to flow within it, Large surface area for reabsorption, Distance for reabsorption of water by osmosis and other substances by active transport is reduced, Transport reabsorbed substances from the proximal tubule to a branch of the renal vein
37
What is the importance of filtration
Filtration provides a way to remove nitrogen-containing waste and other small substances from the blood stream e.g. the breakdown of the products of hormones and drugs
38
What is the importance of reabsorption
it is selective, so specific substances in the glomerular filtrate can be returned to the blood stream but not others e.g. substances the body needs like water and glucose
39
Together filtration and selective reabsorption do what?
allow unwanted substances to leave the body in urine
40
In order for the body to function normally what has to be kept relatively constant?
the temperature and content of its 'body fluids' - that is the tissue fluid in which the cells in the tissue sit and the blood
41
What is maintaining a stable internal environment called?
homeostasis
42
What is an example of homeostasis and what does it involve?
osmoregulation - it involves maintaining the correct balance of water and salts in the blood
43
What is the main site of osmoregulation?
the collecting duct of the nephron
44
What is the osmoregulation at the colleting duct controlled by?
large chemical messenger proteins transported by blood called hormones
45
Name a hormone that plays an important role in osmoregulation
antidiuretic hormone (ADH)
46
Where is antidiuretic hormone (ADH) released from?
an organ of the endocrine system called the pituitary gland
47
More antidiuretic hormone (ADH) makes the collecting duct what?
more permeable to water - meaning it allows water in the glomerular filtrate to move through the collecting duct wall into the medulla by osmosis
48
What does it mean when less ADH is released?
the collecting duct walls become less preamble to water
49
What happens when the water content of the blood starts to become low or it contains to much salt
more antidiuretic hormone (ADH) is released from the pituitary gland - which permits more water to leave the collecting ducts and enter the medulla from where it moves into the bloodstream
50
what is the result of more ADH getting released?
the water and salts content of the blood is returned to the correct balance and a small volume of quite concentrated urine is produced
51
what happens when the water content of the blood starts to become to high or it contains to little salts
less ADH is released which causes less water to leave the collecting ducts and move into the medulla
52
what is the result of less ADH getting released?
a large volume of dilute urine is produced and the water and salt contents of the blood is returned to the correct balance
53
What are the substances that promote urine called?
Diuretics
54
What are two common examples of diuretics
caffeine (coffee, tea, some soft drinks) and alcohol (beer, wine and spirits)
55
Consumption of caffeine or alcohol will lead to what?
the production of a large volume of dilute urine
56
Why does drinking alcohol increase urine production?
because its presences in the blood stream causes the pituitary gland to stop releasing ADH which results in less water leaving the collecting duct by osmosis.
57
What does less water leaving the collecting duct mean?
More water drains into the pelvis and down the ureters to the bladder promoting release of a large volume of urine
58
What does continued consumption of alcohol lead to?
More trips to the toile to urinate and dehydration which could may cause symptoms of a hangover
59
Caffeine is though to what?
block the action of angiotensin which is a hormone in the blood that constricts structures that stem from branch arteries called arterioles
60
what is the result of caffeine blocking angiotensin?
slightly wider arterioles, greater blood flow into the glomerulus and a higher rate of filtration and therefore a higher volume of glomerular filtrate. this may lead to more water passing down the collecting ducts and therefore more urine
61
Are most people able to survive with only one of their kidneys functioning?
Yes.
62
Near or complete breakdown of function of both kidneys results in what?
sever kidney disease and death if not treated
63
What is the way to treat kidney disease?
by some form of kidney replacement therapy
64
What is one kidney replacement therapy?
dialysis
65
What is dialysis do? and how is it performed etc.
in dialysis, the function of the kidney is performed artificially by a kidney dialysis machine. Blood from a vein in the arm is pumped through tubing in the dialysis machine that sits in a fluid. The walls of the tubing have lots of tiny pores in them which mimics filtration - water and small substances including nitrogen-containing wastes are filtered out of the blood into the dialysis fluid, but blood cells or large blood proteins remain in the blood. the concentration of glucose and salts the body needs in dialysis fluid monitored to ensure it stays higher than in the blood - thus loss of these substances from the blood by diffusion is prevented.
66
What is an alternative to dialysis?
a complex surgical replacement procedure called a kidney transplant. this involves removing a diseased kidney from the patient and transferring to them a healthy and functional kidney. the patient is the recipient and the person providing the kidney is the donor.
67
a live donor is what?
a relative that donates one of their kidneys
68
a diseased donor is what?
a healthy person who has died (via car accident etc.)
69
Describe metabolic processes and waste
- processes in the body produce waste products
- excretion removes theses wastes e.g. carbon dioxide and urea
- excretion also includes excess materials e.g. water and salts
70
```
Name the organs of excretion
1.
2.
3.
4.
```
1. skin - excretion of excess water, salts and small amounts of urea as sweat
2. kidney - filtration of the blood to remove urea. Excess water and salts
3. Lungs - excretion of carbon dioxide (CO2), with some loss of water
4. Bladder - storage of urine before it is expelled to the outside
71
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
Describe the vena cava;
the vena cava returns blood to the heart
72
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the kidney;
the kidney produces urine (Blood filtration, the removal of waste products, and the regulation of blood volume)
73
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the renal vein;
returns the blood from the kidney to the venous circulation
74
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the bladder;
stores the urine before it passes out of the body. it can expand to hold about 80% of the daily urine output
75
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the dorsal aorta;
supplies oxygenated blood to the body's tissues and organs
76
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the renal artery;
carries blood from the aorta to the kidney
77
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the ureter;
carries urine to the bladder
78
The urinary system consists of the kidneys and bladder and their associated blood vessels and ducts.
describe the urethra;
conducts urine from the bladder to the outside. the urethra is regulated by a voluntary sphincter muscle
79
Describe the internal kidney structure
The functional unit of the kidney is the nephron
Each kidney contains more than 1 million nephrons
They are selective filter elements
80
Describe the bowman's capsule
Bowman's capsule located in the cortex of the kidney
It encloses a capillary network called the glomerulus
This is where filtration occurs
81
name the elements of the nephron structure
- proximal convoluted tubule
- distal convoluted tubule
- descending limb of the loop of henle
- the collecting duct
- the loop of henle
- blood vessels (the vasa recta)
- ascending limb of the loop of henle
- Venule
- Bownman's capsule
- glomerulus
- efferent arteriole (leaves glomerulus)
- Afferent arteriole (enters glomerulus)
82
Describe the flow of ion and minerals
substances introduced into the nephron will either be reabsorbed or filtered into the collecting duct
the process may be either via passive or active transport
83
Describe the control of urine output
- the primary role of the kidney is to regulate blood volume and composition (including the removal of nitrogenous waste)
- this is achieved through varying the volume and composition of the urine. The hormone antidiuretic hormone (ADH) is involved in that process.
