Unit 8 In Details Flashcards
(107 cards)
1
Q
What is the formula for calculating surface area?
A
LENGTH X WIDTH
This formula applies to flat surfaces.
2
Q
What is the formula for calculating the volume of a block?
A
LENGTH X WIDTH X HEIGHT
This is the standard formula for finding the volume of rectangular prisms.
3
Q
How do you express the surface area to volume ratio in the form n:1?
A
Divide both sides of the ratio by the volume.
4
Q
What is the surface area to volume ratio of a mouse represented by a 1 cm x 1 cm x 1 cm block?
A
6:1
5
Q
What is the surface area to volume ratio of a hippo represented by a 2 cm x 4 cm x 4 cm block?
A
2:1
6
Q
Why do multicellular organisms have a smaller surface area to volume ratio compared to single-celled organisms?
A
They have larger volumes, making it difficult to exchange substances efficiently.
7
Q
Fill in the blank: The total surface area of a block is the sum of the areas of its _______ surfaces.
A
all
8
Q
True or False: Single-celled organisms can directly diffuse gases and dissolved substances into and out of the cell.
A
True
9
Q
What is the significance of the surface area to volume ratio in organisms?
A
It affects how easily substances can be exchanged with the environment.
10
Q
What does diffusion involve in the context of organisms exchanging substances?
A
Movement of molecules from areas of higher concentration to lower concentration.
11
Q
What waste product do animals produce from proteins?
A
Urea
12
Q
In animals, how do cells take up water?
A
By osmosis
13
Q
What is necessary for aerobic respiration in cells?
A
Oxygen
14
Q
What does the exchange of materials in animals depend on?
A
Surface area to volume ratio
15
Q
What needs to be exchanged for removal from the body by the kidneys?
A
Substances diffusing from cells to blood plasma
16
Q
Fill in the blank: A ratio shows how big one value is compared to _______.
A
another
17
Q
What is a key factor that affects how easily an organism can exchange substances with its environment?
A
Surface area to volume ratio
18
Q
What are the alveoli?
A
Exchange surfaces found in the lungs of mammals, adapted for efficient gas exchange of oxygen and carbon dioxide.
19
Q
What is the rate of diffusion affected by?
A
Three factors:
* Distance
* Concentration difference (gradient)
* Surface area
20
Q
How does distance affect the rate of diffusion?
A
Substances diffuse more quickly when they don’t have as far to move.
21
Q
What happens to the rate of diffusion with a concentration gradient?
A
Substances diffuse faster if there’s a big difference in concentration between the two areas.
22
Q
How does surface area influence the rate of diffusion?
A
The more surface there is available for molecules to move across, the faster they can diffuse.
23
Q
What is the primary function of the lungs?
A
To transfer oxygen (O₂) to the blood and remove waste carbon dioxide (CO₂) from it.
24
Q
Where does gas exchange occur in mammals?
A
In the alveoli.
25
What is the state of blood arriving at the alveoli?
It contains lots of CO₂ and not much O₂, maximizing the concentration gradient for diffusion.
26
Describe the direction of diffusion for O₂ and CO₂ in the alveoli.
O₂ diffuses from the alveoli into the blood, and CO₂ diffuses from the blood into the alveoli.
27
List three adaptations of the alveoli for gas exchange.
* A moist lining for dissolving gases
* A good blood supply to maintain concentration gradients
* Very thin walls to minimize gas movement distance
28
What does Fick's Law describe?
The rate of diffusion in relation to surface area, concentration difference, and thickness of the membrane.
29
What does the equation for Fick's Law involve?
30
True or False: The alveoli have a low surface area.
False.
31
What would happen without gas exchange surfaces like the alveoli?
Multicellular organisms wouldn't be able to absorb oxygen quickly.
32
What is blood classified as?
A tissue
## Footnote
Blood acts as a huge transport system in the body.
33
What is the primary function of red blood cells?
To carry oxygen from the lungs to all the cells in the body
34
What shape do red blood cells have?
Biconcave disc shape
35
Why do red blood cells lack a nucleus?
To allow more room to carry oxygen
36
What pigment do red blood cells contain?
Haemoglobin
37
What does haemoglobin bind to in the lungs?
Oxygen to become oxyhaemoglobin
38
What happens to oxyhaemoglobin in body tissues?
It splits into haemoglobin and oxygen to release oxygen to the cells
39
Do white blood cells have a nucleus?
Yes
40
What are platelets?
Small fragments of cells with no nucleus
41
What is the role of phagocytes?
To engulf unwelcome microorganisms through phagocytosis
42
What do lymphocytes produce?
Antibodies against microorganisms and some produce antitoxins
43
What indicates a possible infection in a blood test?
A high white blood cell count
44
What is the function of platelets?
To help blood clot at a wound
45
What can lack of platelets cause?
Excessive bleeding and bruising
46
What is plasma?
A pale straw-coloured liquid that carries everything in blood
47
What does plasma carry? (name at least three)
* Red and white blood cells
* Platelets
* Nutrients like glucose and amino acids
* Hormones
* Proteins
* Carbon dioxide
* Urea
* Antibodies and antitoxins
48
What happens to red blood cell production at high altitudes?
People produce more red blood cells to compensate for less oxygen
49
What can blood tests diagnose?
Various disorders, not just those of the blood
50
Fill in the blank: The job of red blood cells is to carry _______ from the lungs.
Oxygen
51
True or False: White blood cells are responsible for oxygen transport.
False
52
Outline three ways in which red blood cells are adapted to carry oxygen.
* Biconcave shape for large surface area
* Lack of nucleus for more space
* Presence of haemoglobin
53
What is the advantage of capillary walls being only one cell thick?
Increases the rate of diffusion by decreasing the distance over which it occurs.
## Footnote
This allows for efficient exchange of substances between blood and tissues.
54
How are veins adapted to carry blood back to the heart?
Veins have:
* Valves to help keep blood flowing
* Larger lumen than arteries
* Thinner walls due to lower blood pressure
* Capillaries joining to form veins
## Footnote
These adaptations help accommodate the lower pressure and ensure unidirectional blood flow.
55
What is the approximate length of blood vessels in the human body?
About 60,000 miles.
## Footnote
This extensive network facilitates efficient circulation.
56
What type of blood vessels are involved in the exchange of materials at the tissues?
Capillaries.
## Footnote
Capillaries allow for the diffusion of food and oxygen while removing waste like CO2.
57
What is the lumen of a blood vessel?
The central cavity through which blood flows.
## Footnote
The lumen size varies among different types of blood vessels.
58
True or False: Arteries carry blood away from the heart.
True.
## Footnote
Arteries transport oxygenated blood (except for pulmonary arteries) under high pressure.
59
Fill in the blank: Capillaries are really ______, too small to see.
tiny.
## Footnote
Their small size allows them to penetrate tissues effectively.
60
What structural features do arteries have?
Arteries have:
* Thick walls
* Elastic fibers
* Smooth muscle
## Footnote
These features allow arteries to withstand and regulate high pressure from the heart.
61
What do capillaries supply to cells?
Food and oxygen.
## Footnote
They also remove waste products like CO2.
62
What is the role of valves in veins?
To help keep blood flowing in one direction.
## Footnote
Valves are crucial in preventing backflow due to lower pressure in veins.
63
What happens to arteries as they branch?
They branch into capillaries.
## Footnote
This branching is essential for reaching all tissues in the body.
64
How do the walls of veins compare to those of arteries?
Vein walls are thinner than artery walls.
## Footnote
This difference is due to the lower pressure of blood in veins.
65
What facilitates the stretch and recoil of arteries?
Elastic fibers.
## Footnote
These fibers enable arteries to handle the pressure of blood pumped from the heart.
66
What type of blood vessel has permeable walls?
Capillaries.
## Footnote
This permeability allows substances to diffuse in and out effectively.
67
What is the significance of the large lumen in veins?
It helps accommodate larger volumes of blood.
## Footnote
Larger lumen size is important for the return of blood to the heart.
68
Fill in the blank: The heart pumps blood out at ______ pressure.
high.
## Footnote
This high pressure is necessary for efficient circulation through arteries.
69
What is the primary function of the heart?
The heart pumps blood around the body.
70
What type of circulatory system do mammals have?
Mammals have a double circulatory system.
71
How many chambers does the mammalian heart have?
The mammalian heart has four chambers.
72
What is the first circuit of blood flow in mammals?
Deoxygenated blood is pumped to the lungs to take in oxygen.
73
What happens to oxygenated blood after it returns to the heart?
It is pumped around the body to deliver oxygen to the cells.
74
What type of circulatory system do fish have?
Fish have a single circulatory system.
75
What is the pathway of deoxygenated blood in fish?
Deoxygenated blood travels from the body to the heart, then to the gills for oxygen.
76
Which chamber of the heart receives deoxygenated blood from the body?
The right atrium.
77
What chamber pumps deoxygenated blood to the lungs?
The right ventricle.
78
Which chamber receives oxygenated blood from the lungs?
The left atrium.
79
What chamber pumps oxygenated blood around the body?
The left ventricle.
80
Why does the left ventricle have a thicker wall than the right ventricle?
It needs more muscle to pump blood around the whole body at high pressure.
81
What is the function of valves in the heart?
Valves prevent the backflow of blood in the heart.
82
What is cardiac output?
The total volume of blood pumped by a ventricle every minute.
83
How can you calculate cardiac output?
Cardiac output = heart rate X stroke volume.
84
What does stroke volume represent?
The volume of blood pumped by one ventricle each time it contracts.
85
If you know the cardiac output and heart rate, how can you find the stroke volume?
Rearrange the formula: stroke volume = cardiac output / heart rate.
86
Fill in the blank: A fish's heart only has _______ chambers.
two
87
What is the average heart rate if the stroke volume is 72 cm³ and cardiac output is 5420 cm³/min?
75 bpm
88
Fill in the blank: Blue represents _______ blood and red represents _______ blood.
deoxygenated; oxygenated
89
What should you learn regarding the heart for the exam?
The diagram of the heart and all its labels.
90
Calculate the stroke volume for a heart rate of 67 bpm and a cardiac output of 4221 cm³/min.
Stroke volume = cardiac output / heart rate = 4221 cm³/min / 67 bpm.
91
What caused the student to get cramp in his leg after five minutes of intense sprinting?
Lactic acid buildup from anaerobic respiration
## Footnote
Anaerobic respiration occurs when the body cannot supply enough oxygen during vigorous exercise, leading to cramp and pain.
92
What type of respiration occurs when oxygen is not available?
Anaerobic respiration
## Footnote
Anaerobic respiration transfers much less energy than aerobic respiration.
93
What is the word equation for anaerobic respiration in animals?
Glucose → Lactic acid + Energy
## Footnote
This process is less efficient compared to aerobic respiration.
94
What is produced during anaerobic respiration in plants?
Ethanol (alcohol) and Carbon dioxide
## Footnote
The anaerobic respiration in plants has different products compared to animals.
95
How does anaerobic respiration differ from aerobic respiration?
Anaerobic respiration occurs without oxygen and transfers less energy
## Footnote
Aerobic respiration requires oxygen and is more efficient.
96
What happens to glucose during anaerobic respiration?
It is partially broken down
## Footnote
This results in the production of lactic acid in animals or ethanol and carbon dioxide in plants.
97
What is the word equation for aerobic respiration?
Glucose + Oxygen → Carbon dioxide + Water + Energy
## Footnote
This equation shows the complete breakdown of glucose with oxygen.
98
What does aerobic respiration require?
Plenty of oxygen
## Footnote
Aerobic respiration is more efficient in energy transfer compared to anaerobic respiration.
99
What type of reaction is respiration classified as?
Exothermic reaction
## Footnote
Energy is released during the process of respiration.
100
What is respiration NOT synonymous with?
Breathing in and breathing out
## Footnote
Respiration refers specifically to the biochemical process of energy release from organic compounds.
101
What is the primary energy source for cellular processes?
Food
## Footnote
Energy from food is released by respiration in living organisms.
102
Fill in the blank: Anaerobic respiration is defined as respiration that occurs __________.
without oxygen
103
What is the primary function of respiration in living organisms?
To release energy from organic compounds
## Footnote
This process is crucial for maintaining cellular functions and metabolism.
104
True or False: Anaerobic respiration is more efficient than aerobic respiration.
False
## Footnote
Anaerobic respiration transfers much less energy than aerobic respiration.
105
What are the two types of respiration mentioned?
Aerobic and Anaerobic
## Footnote
Both types of respiration are essential for energy production in different conditions.
106
PRACTICAL
Investigating Respiration
You Can Measure the Rate of Respiration Using a Respirometer
In aerobic respiration, organisms use up oxygen from the air. By measuring the amount of oxygen consumed by organisms in a given time, you can calculate their rate of respiration. Here's an experiment which uses woodlice, a water bath and a piece of equipment called a respirometer. It allows you to measure the effect of temperature on the rate of respiration of the woodlice. (You could use germinating peas or beans instead of woodlice. Germinating seeds respire to provide energy for growth.)
1) Firstly, some soda lime granules are added to two test tubes. Soda lime absorbs the CO2 produced by the respiring woodlice in the experiment.
2) A ball of cotton wool is placed above the soda lime in each tube. Woodlice are placed on top of the cotton wool in one tube. Glass beads with the same mass as the woodlice are used in the control tube.
3) The respirometer is then set up as shown in the diagram.
4) The syringe is used to set the fluid in the manometer to a known level.
5) The apparatus is then left for a set period of time in a water bath set to 15 °C.
6) During this time, there'll be a decrease in the volume of the air in the test tube containing the woodlice. This is because the woodlice uses up oxygen in the tube as they respire. (The CO2 they produce is absorbed by the soda lime so it doesn't affect the experiment.)
7) The decrease in volume reduces the pressure in the tube, causing the coloured liquid in the manometer to move towards the test tube containing the woodlice.
8) The distance moved by the liquid in a given time is measured the value can then be used to calculate the volume of oxygen taken in by the woodlice per minute. This gives you the rate of respiration in e.g. cm3 min -1.
9) Repeat steps 1-8 with the water bath set at different temperatures, e.g. 20 °C and 25 °C. This will allow you to see how changing the temperature affects the rate of respiration.
Any live animals you use in this experiment should be treated ethically. E.g. it's important not to leave the woodlice in the respirometer for too long, or they may run out of oxygen and die.
107
Cardiac output def
Cardiac output (CO) is the amount of blood pumped by the heart minute
