Workbook 3 Flashcards
1
Q
What is the relationship between surface area to volume ratio and metabolic rate?
A
The lower the surface area to volume ratio, the smaller the metabolic rate.
2
Q
What adaptations do organisms with a high metabolic rate have for gas exchange?
A
Specialised structures like lungs and gills.
3
Q
Name three examples of adaptations that increase surface area for gas exchange.
A
- Gill filaments and lamellae in fish
- Microvilli
- Lungs with numerous alveoli
4
Q
Fill in the blank: A mouse has a high metabolic rate and does more respiration to produce more _______.
A
[heat]
5
Q
What is the main purpose of having a large surface area to volume ratio in organisms?
A
To increase the surface area for heat loss.
6
Q
True or False: Small organisms have a small surface area to volume ratio.
A
False
7
Q
What is the function of spiracles in insects?
A
They allow air to enter and exit the tracheal system.
8
Q
How does increased lactic acid in cells affect gas exchange in insects?
A
It decreases water potential, causing water to move from tracheoles into the cells by osmosis.
9
Q
What is the role of the countercurrent flow system in fish gills?
A
It allows blood to continually meet water with a higher concentration of oxygen.
10
Q
What is the significance of having thin epithelial cells in gas exchange?
A
They provide a short distance for diffusion.
11
Q
Fill in the blank: Gas exchange in plants occurs mainly through _______.
A
[stomata]
12
Q
What adaptations do xerophytes have to reduce water loss?
A
- Thick waxy cuticle
- Sunken stomata
- Leaf hairs
- Rolled leaves
13
Q
What is the effect of light on stomatal opening in plants?
A
The brighter the light, the wider the stomata open, increasing the rate of transpiration.
14
Q
How do guard cells control the opening and closing of stomata?
A
They change shape to open or close the stomata.
15
Q
What happens to the concentration gradient of carbon dioxide during the day in plants?
A
There is a net uptake of carbon dioxide.
16
Q
What is the role of the trachea in human gas exchange?
A
It conducts air to and from the lungs.
17
Q
Fill in the blank: The volume of air taken in at each breath is known as _______.
A
[tidal volume]
18
Q
What is the importance of maintaining a concentration gradient in gas exchange?
A
It ensures efficient diffusion of gases.
19
Q
True or False: The blood and water flow in the same direction in fish gills.
A
False
20
Q
What is the effect of a thick cuticle on a leaf?
A
It stops uncontrolled evaporation from leaf cells.
21
Q
Why do smaller animals lose heat faster than larger animals?
A
They have a higher surface area to volume ratio.
22
Q
What happens to oxygen uptake as body mass increases?
A
Oxygen uptake (kg-1) decreases.
23
Q
What is the role of capillaries in the lungs?
A
They facilitate gas exchange by being close to alveoli.
24
Q
Fill in the blank: The process of gas exchange in humans involves diffusion across _______ cells.
A
[epithelial]
25
What adaptation allows plants to maintain humidity around stomata?
Leaf hairs.
26
How does the presence of multiple capillaries benefit gas exchange in the lungs?
They provide a large surface area for diffusion.
27
What happens to FEV as age increases for smokers and non-smokers?
FEV decreases with age for both smokers and non-smokers.
## Footnote
Non-smokers do not develop emphysema by age 75, while long-term smoking decreases FEV more significantly.
28
At what age do emphysema symptoms typically develop?
Emphysema symptoms develop at age 55.
29
What is the age range for severe disability due to emphysema to develop?
Severe disability due to emphysema develops between ages 60 and 62.
30
What indicates that differences in results are significant?
Bars or standard deviations do not overlap.
31
What is the effect of a closed window on CO concentrations compared to no smoking?
Significantly higher concentrations of CO with closed windows, as there is no overlap in 2 × SD.
32
True or False: Any increase in CO could be dangerous.
True.
33
What is a potential danger of CO in relation to children?
CO causes less oxygen to be carried, which could be deadly in children.
34
What does the graph indicate about CO levels after 5 minutes with closed windows?
There are significantly higher levels of CO after just 5 minutes.
35
What does a lack of significant difference in CO levels with an open window suggest?
The difference could be due to chance.
36
What is the risk associated with a husband who smokes?
There’s a greater risk of dying from lung cancer, emphysema, or cervical cancer.
37
What is the relationship between the amount a husband smokes and the risk of dying from lung cancer?
The more the husband smokes, the greater the risk of dying from lung cancer or emphysema.
38
What is the significance of a sample size of 540 women in a study?
It is large enough to be representative and provide reliable results.
39
What does the term 'simple diffusion' refer to?
The process by which substances move from an area of higher concentration to an area of lower concentration.
40
What structural features of the alveoli facilitate effective gas exchange?
Thin walls, large surface area, and short diffusion distance.
41
What happens to the diaphragm during inhalation?
The diaphragm contracts and moves down.
42
What is the result of diaphragm contraction on thoracic pressure?
It decreases pressure in the thorax.
43
What is the primary function of amylase in digestion?
To hydrolyse starch into maltose.
44
Fill in the blank: The emulsion test is used to test for _______.
lipid.
45
What is the role of bile in lipid digestion?
Emulsifies lipids to form small droplets, increasing surface area for hydrolysis by lipase.
46
What is the significance of the sodium-potassium pump in nutrient absorption?
It actively transports sodium ions, creating a concentration gradient that facilitates the co-transport of glucose and amino acids.
47
What is the role of villi in the small intestine?
Increase surface area for absorption.
48
What are the main components of a lipid molecule?
Phospholipids, bile salts, fatty acids, and monoglycerides.
49
What is the primary function of endopeptidases?
Hydrolyse internal peptide bonds.
50
What is the result of the Bohr Effect on hemoglobin's affinity for oxygen?
Decreased affinity for oxygen in response to increased CO2 concentration.
51
What is the significance of the binding of the first oxygen molecule to hemoglobin?
It changes the tertiary structure of hemoglobin and uncovers the second binding site.
52
What happens to the pH level when starch is digested?
pH goes down and levels out.
53
What are the components of the digestive system responsible for hydrolysis?
Amylase, maltase, endopeptidase, exopeptidase, and dipeptidase.
54
What type of bond is formed between glucose molecules in starch?
Glycosidic bond.
55
Fill in the blank: Proteins are synthesized by _______.
ribosomes.
56
What is the role of ATP in active transport?
Provides energy for transport against a concentration gradient.
57
What is a biochemical test for reducing sugars?
Add Benedict’s solution and heat; a positive test turns brick red or orange.
58
How many oxygen molecules does each haemoglobin carry?
4
59
What is the total number of oxygen molecules carried by each RBC?
1.12 x 10^9
60
How many RBCs are there in 1µl of blood?
5 million
61
What is the total number of oxygen molecules carried in 1 µl of blood?
5.6 x 10^15
62
How many µl are there in a litre?
1,000,000
63
What is the total number of oxygen molecules carried in the human body?
2.8 x 10^22
64
Fill in the blank: haemoglobin ‘loads oxygen’ should use the words mentioned by the MS: carries oxygen / has a high affinity for oxygen / forms _______.
oxyhaemoglobin
65
Where is the partial pressure of oxygen highest?
in the lungs
66
What is the maximum number of marks for the answer regarding haemoglobin's function?
5 marks
67
What type of structure do haemoglobin polypeptides form?
quaternary structure
68
What causes the atrioventricular (AV) valve to close?
high blood pressure during ventricular contraction
69
What happens to the pressure in the ventricles during ventricular contraction?
It becomes higher than in the atria.
70
What is the primary role of the left ventricle?
Pumps blood to the whole body (except lungs)
71
What is the function of the semi-lunar valve?
Prevents backflow of blood into the ventricles
72
True or False: The blood pressure is higher in the arteries than in the veins.
True
73
What is hydrostatic pressure?
The pressure exerted by a fluid at rest
74
What is the role of the lymphatic system?
Drains excess tissue fluid
75
Fill in the blank: The overall outward pressure of _______ kPa forces small molecules out of the capillary.
3.2
76
What happens to fluid return into the capillary due to pressure changes?
Less return of fluid occurs
77
What is the effect of a larger lumen in blood vessels?
Reduces blood pressure
78
How does high blood pressure affect tissue fluid formation?
Increases tissue fluid formation
79
What is the result of a smaller mammal having a greater surface area to volume ratio?
More heat lost per unit body mass
80
What does cooperative binding in haemoglobin refer to?
The increased affinity of Hb for O2 as oxygen binds
81
What is required for respiration that leads to oxygen release from haemoglobin?
Higher carbon dioxide concentration
82
What is fetal haemoglobin's primary advantage?
Greater affinity for oxygen
83
What is the overall outward pressure in capillaries?
3.2 kPa
84
What do small molecules being forced out of capillaries indicate?
Hydrostatic pressure
85
What causes loss of fluid against the capillary lining?
Friction
86
What is the relationship between high blood pressure and hydrostatic pressure?
High blood pressure = high hydrostatic pressure
87
How does high hydrostatic pressure affect tissue fluid formation?
Increases outward pressure from arterial end, reduces inward pressure at venule end
88
What happens to tissue fluid formation under high blood pressure?
More tissue fluid is formed; less is reabsorbed
89
What is one consequence of the lymph system not being able to drain tissues fast enough?
Accumulation of tissue fluid
90
What happens to water when it leaves the capillary?
Proteins remain, increasing concentration of blood proteins
91
What is a key characteristic of capillaries compared to arterioles?
More capillaries than arterioles
92
What is the cross-sectional area of capillaries compared to arterioles?
Greater than that of arterioles
93
What facilitates fast exchange in capillaries?
Short pathway between blood and outside of capillary
94
What allows for a large surface area of blood in contact with capillary walls?
Numerous capillaries
95
What is the maximum distance for efficient diffusion in capillaries?
Short diffusion distance
96
What is one effect of the contraction of muscle in relation to arterioles?
Narrowing of the arteriole
97
What happens to the lumen of a blood vessel during vasoconstriction?
Narrows
98
What is the significance of having a thin diffusion pathway in capillaries?
Short diffusion distance
99
What is a key feature of the endothelium in blood vessels?
It reduces friction
100
What is the primary function of elastic tissue in arteries?
Maintaining pressure
101
What occurs when elastic tissue in arteries stretches?
It recoils to maintain pressure
102
What is the diameter of blood cells relevant to blood flow?
Width/size must be below a certain diameter to reduce friction
103
What is a characteristic of veins compared to arteries?
Thin wall does not have to withstand high pressure
104
What is the primary role of muscle in the walls of arteries?
Controls blood flow
105
What are the two main components of tissue fluid?
Fluid in tissue fluid and fluid in lymph
106
What is a key difference between lymph and blood plasma?
Lymph has no plasma protein
107
What role do valves in veins play?
Prevent back-flow of blood
108
What causes the pressure in arteries to decrease?
Friction from contact with the wall
109
What drives water to move back into blood by osmosis?
Higher concentration of proteins in blood
110
What happens to hydrostatic pressure at the arteriole end of capillaries?
It is high and forces out small molecules
111
What is the effect of osmotic pressure in blood?
It draws water back into the blood
112
What is the characteristic of capillary walls?
One cell thick
113
What is a significant factor for efficient exchange in capillaries?
Gaps between cells increase permeability
114
What is the primary driver for blood flow in veins?
Contraction of skeletal muscles
115
What characterizes the blood flow in arteries?
Thickest wall to withstand high pressure
116
What is the measurement to determine pressure in blood vessels?
Measurement divided by 8
117
What is the result of high hydrostatic pressure in tissue fluid formation?
Forces/squeezes water and small molecules out
118
What happens to blood pressure after approximately 0.5 mm in capillaries?
Pressure decreases more acutely
