Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

IB Bio HL > B3.1 Gas Exchange > Flashcards

B3.1 Gas Exchange Flashcards

(58 cards)

Start Studying
1
Q

how maintaining steep conc. gradient for gas excahnge?

A
  • dense blood vessel network
  • continuous blood flow
  • ventilation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

properties gas exchange surface

A
  • moist surface => dissolve gases
  • large SA
  • permeability
  • thin tissue layer
  • concnetration gradient
  • good blood supply
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Type II pneumocytes

A
  • gas exchange
  • make alveolar fluid surfactant = moist
  • reduces cell tension & prevents collapsing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

bronchioles adaptation

A

*thin muscle layer to alter diamter
* bronchi branches
* increase SA = more gas exchange & even distribution

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

extensive capillary bed

A
  • many
  • shorter oxygen diffusion path
  • more alveoli = larger SA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

thoraic cavity

A

volume within your chest

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

quiet breathing

A

passive breathing done at rest

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

forced breathing

A

active breathing utilising muscles to rapidly expand and contract the thoraic cavity

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

forced vital capacity

A

volume of air you can exhale with maximum effort after inhaling the maximum volume of air

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

residual volume

A

volume remaining in the lungs that cannot be exhaled

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

tidal volume

A

volume of air that moves into and out of your lungs with every normal breath

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

inspiratory reserve

A

extra volume of air that can be inhaled with maximum effort beyond the volume of air inhaled in a normal inspiration

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

expiratory reserve

A

extra volume that can be exhaled with maximum effort beyond the volume exhaled in a normal expiration

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

factors affecting lung capacity

A
  • age
  • respiratory disease
  • body size
  • biological sex
  • level of physical activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

measuring lung capacity

A

spirometer (measures exhale speed & volume)

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

Pressure when inhaling

A
  • inhale
  • thoraic cavity increases
  • particles collide less frequently with walls
  • pressure decreases
  • air flows in
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pressure when exhaling

A
  • exhale
  • thoraic cavity decreases
  • lesss space
  • particles collide more frequently
  • pressure increases
  • forces air out
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Inhalation steps

A
  1. diaphragm contracts & moves down/flattens
  2. external intercostal muscle contracts
    Internal intercostal muscles relax
  3. rib cage goes up & out
  4. increases thoraic cavity
  5. decreased pressure
  6. air moves down pressure gradient => in
    (COMPARE TO ATMOSPHERIC PRESSURE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(forced) Exhale steps

A
  1. diaphragm relaxes & moves up & in
  2. external intercostal muscle relaxes
  3. Internal intercostal muscles contracts
  4. rib cage goes down & in (FORCEFULLY)
  5. decreases thoraic cavity
  6. increased pressure
  7. air moves (QUICKLY) down pressure gradient => out
    (COMPARE TO ATMOSPHERIC PRESSURE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the main tissues found in a leaf?

A

Epidermal tissue, mesophyll tissue, vascular tissue

These tissues play distinct roles in protecting, facilitating photosynthesis, and transporting substances.

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

What is the function of the epidermis in a leaf?

A

Forms the outer boundary of the leaf and protects the inner parts

It consists of a single layer of tightly packed cells.

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

What are stomata?

A

Tiny pores in the lower epidermis of the leaf

They are surrounded by guard cells and facilitate gas exchange.

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

How do guard cells function?

A

Control the opening and closing of stomata

They become turgid to open stomata and flaccid to close them.

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

What is the role of mesophyll tissue?

Study These Flashcards
A

Site of photosynthesis in the leaf

Formed by parenchyma cells containing chloroplasts.

22
What are the two types of mesophyll tissue?
Palisade mesophyll, spongy mesophyll ## Footnote Palisade mesophyll is rich in chloroplasts, while spongy mesophyll has air spaces for gas exchange.
23
What is the primary function of vascular tissue in leaves?
Transport substances between the leaf and the rest of the plant ## Footnote It forms vascular bundles, or veins, in leaves.
24
What does xylem transport?
Water and mineral ions from the roots to the leaves ## Footnote Essential for photosynthesis and plant hydration.
25
What does phloem transport?
Products of photosynthesis from the leaves to other parts of the plant ## Footnote It plays a critical role in nutrient distribution.
26
What is the function of the waxy cuticle?
Prevents gases and water vapor from leaving through the epidermis ## Footnote This ensures gas exchange occurs primarily through stomata.
27
How do air spaces in the leaf contribute to gas exchange?
Maintain a concentration gradient of gases ## Footnote They allow for the movement of gases between the air and spongy mesophyll cells.
28
What is transpiration?
Loss of water vapor from leaves through stomata ## Footnote It is a consequence of gas exchange necessary for photosynthesis.
29
What are the advantages of transpiration for plants?
* Cooling the plant via evaporation * Aiding in the uptake of mineral ions * Providing turgor pressure for support ## Footnote Turgor pressure helps maintain leaf structure and surface area for photosynthesis.
30
How does air movement affect the rate of transpiration?
Increased air movement leads to higher rates of transpiration ## Footnote Wind carries water molecules away from the leaf surface, increasing the concentration gradient.
31
How does temperature influence transpiration rates?
Higher temperatures increase transpiration rates up to a limit ## Footnote Increased kinetic energy of molecules enhances evaporation.
32
What effect does light intensity have on transpiration?
Higher light intensities increase transpiration rates until leveling off ## Footnote Stomata open in light, facilitating gas exchange and water loss.
33
How does humidity affect transpiration rates?
Higher humidity levels reduce the rate of transpiration ## Footnote Saturated air decreases the concentration gradient, leading to less water vapor loss.
34
What is a potometer used for?
Measuring the rate of transpiration in plants ## Footnote It indirectly measures water uptake, which correlates with transpiration.
35
What is the difference between bubble potometers and mass potometers?
* Bubble potometers measure air bubble movement in a water-filled tube * Mass potometers measure change in mass of a water-filled test tube ## Footnote Both methods assess water uptake related to transpiration.
36
37
How many polypeptide subunits does each haemoglobin molecule consist of?
Four polypeptide subunits
38
How many oxygen molecules can one haemoglobin molecule transport?
Four oxygen molecules
39
axis of oxygen dissociation curve
x =The partial pressure of oxygen y= % saturation of O2
40
What is cooperative binding in the context of haemoglobin?
The change in shape that facilitates the binding of additional oxygen molecules after the first one
41
Where is the affinity of haemoglobin for oxygen high?
In areas with high partial pressures of oxygen (alveoli)
42
Where is the affinity of haemoglobin for oxygen low?
In areas with low partial pressures of oxygen (respiring muscle cells
43
What happens to foetal haemoglobin at low pO2?
It can bind to oxygen while the mother's haemoglobin is dissociating with oxygen
44
curve foetal haemoglobin vs adult haemoglobin?
Foetal = shifts left => indicating a higher percentage saturation at any given partial pressure of oxygen => has higher O2 affinity
45
What are allosteric proteins?
Proteins that can exist in multiple conformations
46
What role does carbon dioxide play in relation to haemoglobin?
It is an allosteric inhibitor that lowers the affinity of haemoglobin for oxygen
47
How does carbon dioxide affect foetal haemoglobin compared to adult haemoglobin?
It has less of an allosteric effect, allowing foetal haemoglobin to maintain a higher affinity for oxygen
48
49
What is the Bohr effect?
Changes in the oxygen dissociation curve as a result of carbon dioxide levels
50
O2 affinity vs CO2 conc
CO2 high = lower affinity
51
In which tissues does the Bohr effect primarily occur?
Respiring tissues
52
Why does CO2 lower the pH of the blood?
CO2 combines with water to form carbonic acid => dissociates to protons
53
How do hydrogen ions affect haemoglobin?
They bind to haemoglobin, causing the release of oxygen
54
What does a rightward shift in the dissociation curve indicate?
Lower percentage saturation of haemoglobin at given partial pressure of oxygen
55
alveoli process
* site of gas exchange in lungs (hang off of brinchioles) * dense capillary network * oxygen pressure gradient * oxygen diffuses down gradient out; CO2 diffuses in * pressure in alveoli decreases during expiration * type 2 pneumocytes = surfactant on side for adhering

IB Bio HL (29 decks)

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