Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Minne Life Cycles and Adaptations of Marine organisms > Physiology Respiratory System > Flashcards

Physiology Respiratory System Flashcards

(105 cards)

Start Studying
1
Q

What is ventilation in the context of the respiratory system?

A

Ventilation is the renewal of air or water in contact with the body surface devoted to the uptake of gases.

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

What are the two main types of respiratory pathways?

A

The two main types are external respiration and internal respiration.

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

What is external respiration?

A

External respiration is the exchange of gases between the lungs and the internal environment.

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

What is internal respiration?

A

Internal respiration is cellular respiration for the oxidation of glucose using O2 to obtain energy, producing water and CO2 as waste products.

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

What is partial pressure (p)?

A

Partial pressure is the individual pressure exerted by a single gas within a mixture of gases.

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

How does the amount of O2 available to aquatic organisms compare to that available to terrestrial organisms?

A

The amount of O2 available to aquatic organisms is about 30 times lower than that available to terrestrial organisms

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

What law explains the difference in O2 amounts in air and water?

A

Henry’s Law explains the difference, stating that the concentration of a gas is proportional to its partial pressure.

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

What factors affect the absorption coefficient of oxygen in water?

A

Temperature and salinity affect the absorption coefficient; higher temperature and salinity lower the dissolution capability of O2 in water.

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

How is the exchange of O2 and CO2 with the external environment achieved?

A

The exchange is achieved by simple diffusion following the 1st Fick’s law.

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

What does the 1st Fick’s law state about solutes?

A

Solutes move down a concentration gradient, and this process doesn’t require energy as it is passive.

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

What is the equation for the rate of diffusion (Q) according to Fick’s law?
What do the variables in the diffusion rate equation represent?

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

How do small organisms with simple organization achieve respiratory exchange?

A

They have a short distance (Δx) between cells and the external medium, allowing for efficient gas exchange.

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

How have large animals solved the problem of distance in gas exchange?

A
  • they evolved a circulatory system
  • expanded the exchange surfaces (A)
  • increased the partial pressure gradient of O2 (ΔpO2)
  • enhanced O2 solubility with molecules like hemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the five main gas exchange mechanisms in the animal kingdom?

A
  1. Simple diffusion
  2. tidal exchange
  3. cocurrent exchange
  4. countercurrent exchange
  5. crosscurrent exchange.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the simple diffusion mechanism of gas exchange.

A

The external fluid does not circulate while the internal fluid is renewed. The gradient in pO2 is determined by O2 consumption by cells or the presence of a respiratory pigment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In which organisms is simple diffusion present?

A

It is present in unicellular organisms, diblastic animals (e.g., sponges, cnidarians), and some triblastic animals with integumentary respiration (e.g., flatworms, amphibians).

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

Describe the tidal exchange mechanism of gas exchange.

A

Both the external fluid (usually air) and the internal fluid are renewed, with pO2 gradient favored by ventilation and the binding of O2 with hemoglobin. This system is present in mammalian lungs.

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

How does air move in tidal exchange?

A

Air enters alveoli during inhalation, exchanges gas with the respiratory surface, and exits with exhalation. There is a mixing of new and old air in the alveoli.

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

Describe the cocurrent exchange mechanism of gas exchange.

A

The external fluid (usually water) and the internal fluid move in the same direction, with the gradient in pO2 being maximal at the beginning of the exchange. This system is typical of the gills of many invertebrates.

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

Why is cocurrent exchange not very efficient?

A

As O2 concentration in blood increases and O2 concentration in water decreases, the diffusion slows down until it stops completely, making it insufficient for fast-moving or large animals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the countercurrent exchange mechanism of gas exchange.

A

The external fluid and the internal fluid flow in opposite directions, maintaining a low but constant pO2 gradient for continuous O2 exchange. This system is found in the gills of teleost fish and the placenta of non-primate mammals.

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

Why is countercurrent exchange efficient?

A

The constant gradient allows for continuous O2 diffusion, making it efficient throughout the length of the respiratory surface.

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

Describe the crosscurrent exchange mechanism of gas exchange.

A

The external fluid and the internal fluid circulate in the same direction, but the afferent vessel temporarily contacts the interface. This is typical of bird lungs and allows high oxygen extraction efficiency.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does the crosscurrent exchange mechanism work in bird lungs?

A

Capillaries from a main vessel contact the exchange surface perpendicularly, allowing sequential uptake of O2 along the capillaries. The final oxygen level in blood is higher than the exhaled air’s oxygen level.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is a key advantage of air-breathing animals regarding oxygen supply?
Air-breathing animals can use an unlimited oxygen supply which is much greater than the amount available to animals using oxygen dissolved in water.
26
Why is ventilation less energy-intensive for air-breathing animals?
- Air is less dense than water, meaning it takes less effort to move it into and out of the lungs or other respiratory organs. - Therefore, air-breathing animals expend less energy in ventilating their respiratory systems compared to water-breathing animals - which must overcome the higher density of water to obtain oxygen
27
How does gas diffusion in air compare to water?
Gas diffusion is faster in air than in water, allowing quicker diffusion inside alveoli and into the blood.
28
What is a major disadvantage of air-breathing animals related to dehydration?
Air-breathing animals face the risk of dehydration because air is a dry fluid, leading to potential water loss through the respiratory surface.
29
Why is it necessary for the respiratory surface of air-breathing animals to have a water layer?
Oxygen must be hydrated to pass through the respiratory surface, so a thin water layer is necessary for the initial solubilization of O2.
30
What challenge do air-breathing animals face regarding the water layer on the respiratory surface?
Maintaining the water layer is difficult due to the high possibility of water evaporation.
31
Why don't water-breathing animals risk dehydration?
Their respiratory surfaces are surrounded by water, preventing dehydration.
32
How is the respiratory surface in water-breathing animals adapted for gas exchange?
The respiratory surface is already in contact with water, making oxygen passage easier since it's already hydrated.
33
What is a significant disadvantage for water-breathing animals regarding oxygen availability?
The amount of O2 in water is smaller because the solubility of oxygen in water is quite low.
34
How does the density of water affect ventilation in water-breathing animals?
Moving water from the external environment to the exchange surface is difficult and requires greater energy consumption.
35
What is integumentary breathing?
Integumentary breathing is the use of the entire body surface for the exchange of O2 and CO2.
36
Which animals primarily use integumentary respiration?
Many small aquatic invertebrates and some large ones like sea spiders use integumentary respiration.
37
How do amphibians utilize integumentary respiration?
Amphibians exchange up to 20% of O2 and up to 90% of CO2 through their skin.
38
How do annelids like Arenicola marina manage respiration?
They extract O2 from water entering their burrow and renew the water by moving in and out of the tube, using a cross-current mechanism for high efficiency.
39
What percentage of oxygen extracted by annelids is devoted to metabolism?
50-60% of the extracted oxygen is devoted to metabolism.
40
What are the main components of fish gills?
Fish gills consist of 4 gill arches, primary lamellae, and secondary lamellae.
41
What is the function of primary lamellae in fish gills?
Primary lamellae increase the surface area for gas exchange.
42
How does countercurrent exchange in fish gills work?
Blood in the secondary lamellae flows in the opposite direction to water, allowing efficient oxygen uptake.
43
What percentage of oxygen can fish extract from water using their gills?
Fish can extract up to 85% of the oxygen in water.
44
What is the structure of mammalian lungs called?
Mammalian lungs are called parenchymatous lungs.
45
What are alveoli?
Alveoli are chambers within the lungs that are highly vascularized and involved in gas exchange.
46
What connects the alveoli to the external environment in mammalian lungs?
Bronchi and bronchioles
47
What are Type I alveolar cells?
Type I alveolar cells are flat cells that form part of the respiratory exchanger surface.
48
What are Type II alveolar cells?
Type II alveolar cells secrete pulmonary surfactant, which helps solubilize O2 and reduce surface tension.
49
How does ventilation in mammals work according to Boyle's law?
Ventilation involves changes in lung volume and pressure; as volume increases, pressure decreases, drawing air in, and as volume decreases, pressure increases, expelling air.
50
What muscles are involved in inspiration in mammals?
The diaphragm and external intercostal muscles are involved in inspiration.
51
What is the difference between passive and active expiration in mammals?
Passive expiration is due to muscle relaxation, while active expiration involves contraction of abdominal and internal intercostal muscles.
52
How do crocodiles manage to spend hours diving?
Crocodiles maintain air inside their lungs, which represents 85% of their oxygen reserve.
53
What adaptation helps Galapagos marine iguanas dive to feed on algae?
They empty their lungs before diving to reduce body density, making it easier to reach deep-sea waters.
54
Where do turtles store their oxygen reserves for diving?
Turtles store oxygen in their lungs, blood, and muscles, with high concentrations of hemoglobin and myoglobin.
55
What specialized structures do turtles use for gas exchange underwater?
Turtles use a very vascularized epithelium in their pharynx and cloaca, particularly the cloacal bursae, for gas exchange.
56
How do sea snakes exchange gases underwater?
Sea snakes exchange oxygen and CO2 through their skin in addition to using their single lung.
57
What problems do diving mammals face?
Diving mammals face barotrauma, hypoxia, nitrogen narcosis, and decompression sickness.
58
How do cetaceans adapt to high pressure when diving?
Cetaceans allow their lungs to collapse under high pressure, preventing nitrogen and oxygen dissolution in the blood.
59
What is the efficiency of air renewal in cetaceans compared to other mammals?
Cetaceans can renew up to 90% of the air in their lungs with a single breath, compared to 10-20% in other mammals.
60
How do pinnipeds protect their middle ear from pressure damage?
They have cavernous sinuses around the middle ear that fill with blood to buffer the effects of pressure.
61
How do seals avoid hypoxia during long dives?
Seals store oxygen mainly in their muscles through high concentrations of myoglobin, reducing reliance on lung oxygen stores.
62
How do penguins store oxygen for diving?
Penguins store oxygen in their muscles through high concentrations of myoglobin and also in their air sacs.
63
How do penguins avoid decompression sickness when ascending from a dive?
Penguins ascend obliquely to slow their ascent and allow the dissolution of nitrogen and oxygen bubbles.
64
What percentage of oxygen in the mammalian circulatory system is bound to hemoglobin?
97%
65
Why is it important for oxygen to be bound to hemoglobin?
It maintains a low amount of free O2 at the respiratory exchanger surface, ensuring a high gradient for continuous O2 passage from lungs to blood.
66
What percentage of CO2 in the blood is bound to hemoglobin as carbamino hemoglobin?
23%
67
In what form is 70% of CO2 in the blood found?
Bicarbonate anion (HCO3‒)
68
What enzyme catalyzes the conversion of CO2 to bicarbonate anion in erythrocytes?
Carbonic anhydrase
69
How does the body prevent pH from dropping due to CO2 hydration in plasma?
Bicarbonate anions react with H+ ions, reducing their amount.
70
What protein exchanges bicarbonate anions and chloride ions across the erythrocyte membrane?
Antiport protein
71
What is the Haldane effect?
Hemoglobin acts as a buffer, binding H+ ions released during CO2 hydration to prevent pH decrease.
72
What is the main function of respiratory pigments?
To facilitate the solubilization of oxygen in blood.
73
What is the most well-known respiratory pigment in vertebrates?
Hemoglobin
74
How does hemoglobin change conformation upon binding oxygen?
It changes from a "tense" (T-state) to a "relaxed" (R-state) conformation, increasing the availability of binding sites for oxygen.
75
What are the four main classes of respiratory pigments?
Hemoglobins, Chlorocruorins, Haemorythrins, Haemocyanins
76
How does the oxygen binding capacity of myoglobin compare to hemoglobin?
Myoglobin binds one oxygen molecule (monomeric), while hemoglobin binds four oxygen molecules (tetrameric).
77
Why does myoglobin have a different oxygen saturation curve compared to hemoglobin?
Myoglobin has a rapid increase in saturation at low pO2 due to its monomeric structure.
78
What is the function of neuroglobins?
To supply oxygen to neurons and other cells during hypoxic conditions.
79
What is the hypothesized function of cytoglobins?
To maintain oxygen levels within a physiological range, preventing hypertoxic conditions.
80
What is the cooperative effect in oxygen binding to hemoglobin?
The binding of the first oxygen molecule makes it easier for subsequent oxygen molecules to bind.
81
How does the body facilitate CO2 elimination at the alveolar level?
Bicarbonate ions re-enter erythrocytes, are converted back to CO2 by carbonic anhydrase, and then diffuse into alveoli.
82
What causes the oxygen-hemoglobin saturation curve to shift to the right?
Increase in temperature, decrease in pH, and increase in CO2 partial pressure (Bohr effect).
83
How does an increase in temperature affect hemoglobin's affinity for oxygen?
It decreases the affinity, making oxygen binding less likely.
84
What is the Bohr effect?
The shift of the oxygen-hemoglobin saturation curve to the right due to a decrease in pH and an increase in CO2 partial pressure, reducing oxygen affinity.
85
How does pH affect hemoglobin's affinity for oxygen at a pH of 7.6 compared to 7.2?
At pH 7.6, hemoglobin's affinity for oxygen is higher, leading to 85% saturation at 30 mmHg, while at pH 7.2, saturation drops to 60%.
86
What happens to hemoglobin's oxygen affinity at high temperatures in the lungs?
It decreases, impairing oxygen loading.
87
How does the Root effect differ from the Bohr effect?
The Root effect affects hemoglobin affinity at both high and low oxygen partial pressures, while the Bohr effect primarily influences low oxygen partial pressures.
88
What is the role of the swim bladder in fish?
It helps fish maintain buoyancy and counteract hydrostatic pressure.
89
How does the Root effect facilitate oxygen diffusion into the swim bladder?
High H+ ion production in the gas gland lowers pH, decreasing hemoglobin's oxygen affinity and enabling oxygen release and diffusion into the swim bladder.
90
What is the function of 2,3-bisphosphoglycerate (2,3-DPG) in mammals?
It decreases hemoglobin's affinity for oxygen, facilitating oxygen release to tissues, especially under conditions of low CO2 partial pressure.
91
How does increased 2,3-DPG production benefit mammals in low oxygen environments?
It compensates for reduced CO2 partial pressure and prevents high hemoglobin saturation at low pO2, ensuring tissues receive enough oxygen.
92
What is a unique adaptation of the icefish regarding respiratory pigments?
Icefish live without hemoglobin, relying on increased diffusion surface area and larger gill and heart size to compensate for oxygen transport
93
Why is the icefish's adaptation of having a larger heart beneficial?
It increases stroke volume, enabling higher blood pressure and more efficient oxygen transport despite the absence of hemoglobin.
94
How do cetaceans manage respiration during sleep?
They alternate the waking state of their cerebral hemispheres, allowing one hemisphere to be alert for breathing while the other is asleep.
95
What is the function of ventilation in the respiratory system?
Ventilation ensures the renewal of air from the external environment to maintain a high gradient for gas exchange.
96
What regulates and generates respiratory frequency in the respiratory system?
Neuronal pattern generator, located in the medulla, controls respiratory rhythm.
97
How is ventilation controlled in terms of muscle activity?
Respiratory muscles, particularly the diaphragm controlled by the phrenic nerve, initiate inspiration through contraction and relaxation for expiration.
98
What role do chemoreceptors play in the control of ventilation?
Chemoreceptors monitor O2 and CO2 levels, with CO2 being the primary regulator due to its potential to alter pH levels.
99
What are the two types of chemoreceptors found in birds and mammals?
Central chemoreceptors (located in the bulbus) are sensitive to pCO2 changes, while peripheral chemoreceptors (in the aorta and carotid) monitor pCO2, pO2, and pH.
100
How do chemoreceptors respond to increased arterial pCO2?
Chemoreceptors stimulate the medullary respiratory center to increase ventilation and reduce arterial pCO2 levels.
101
What are central chemoreceptors more sensitive to?
Central chemoreceptors are more sensitive to increased H+ ions, indirectly reflecting pCO2 levels.
102
What do peripheral chemoreceptors monitor to prevent blood acidosis?
They monitor both pCO2 and H+ ions in blood to prevent acidosis.
103
How does arterial acidosis affect central respiratory centers?
Arterial acidosis doesn't affect central respiratory centers because H+ ions cannot pass the blood-brain barrier to be detected.
104
Where are peripheral chemoreceptors located in fish, and what do they monitor?
Peripheral chemoreceptors in fish are located downstream from the gills and monitor pO2 levels, increasing ventilation in response to hypoxia.
105
What is the function of mechanoreceptors in fish gills?
Mechanoreceptors modulate ventilation by regulating water flow through the gills, influencing the activation of gill muscles.

Minne Life Cycles and Adaptations of Marine organisms (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions