Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > mammalian gas exchange. > Flashcards

mammalian gas exchange. Flashcards

(46 cards)

Start Studying
1
Q

Define tissue? (4)

A
  1. Group of similar cells.
  2. Consisting of one or more than one type.
  3. With any extracellular material they secrete.
  4. Which are specialised to carry out a specific function.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Give 4 examples of tissues. (4)

A
  1. Squamous epithelium.
  2. Ciliated epithelium.
  3. Xylem tissue.
  4. Phloem tissue.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define organ? (3)

A
  1. Group of tissues.
  2. Consisting of one or more than one type.
  3. Which are specialised to carry out specific functions.
    e.g., lungs, leaves, heart.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define system? (2)

A
  1. Collection of organs.
  2. With a specific function.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give two examples of systems? (2)

A
  1. Circulatory system: heart, blood vessels, and blood.
  2. Gas exchange system: lungs, trachea, bronchi, bronchioles, larynx, mouth, and diaphragm.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Function of gas exchange system? (2)

A
  1. Diffusion of respiratory gases: CO2 out and O2 into the bloodstream.
  2. Close relationship with circulatory system to carry exchanged gases to and from lungs.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Rate of diffusion determined by? (1)

A
  1. SA:VOL of the organism -> Increased SA:VOL = Increased rate of diffusion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Diffusion alone is not enough for multicellular organisms. Why? (4)

A
  1. Diffusion alone too slow in multicellular organisms -> Some cells deep within the body -> large diffusion distance between cells + outside environment.
  2. Reduced SA:VOL -> Difficult to exchange enough gases to meet demands and remove waste at suitable rate.
  3. Higher metabolic rate -> Use O2 and produce CO2 at a higher rate.
  4. Hence need specialised exchange system: Alveoli in lungs with huge SA.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does the alveoli having a large SA help with the gas exchange system? (4)

A
  1. Increased SA -> SA of alveoli is huge -> 300-500 million alveoli per adult lung -> total SA = 50-75 m^2
  2. Alveoli can expand during inhalation.
  3. Further increases SA.
  4. more molecules of O2 and CO2 can diffuse per unit time.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does the alveoli being THIN help with the gas exchange system? (6)

A
  1. Each alveoli made from single layer of thin, flat cells -> alveolar epithelium.
  2. Reduces diffusion distance to 0.6-0.7 micrometer.
  3. Increases rate of diffusion.
  4. Capillary walls also only made of one cell.
  5. Hence total diffusion distance between RBC in plasma to air in alveoli is extremely small.
  6. Increases diffusion rate.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the alveoli having a good blood supply help with the gas exchange system? (3)

A
  1. Large capillary network surrounding the alveoli - 280 million capillaries supply the millions of alveoli in each lung.
  2. Maintains concentration gradient.
  3. Enabling O2 and CO2 to be exchanged in opposite directions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does a steep diffusion gradient help the gas exchange system? (2)

A
  1. Pulmonary circulation rapidly delivers oxygenated blood + removes deoxygenated blood.
  2. Pulmonary ventilation replaces CO2 rich air with O2 rich air to maintain diffusion gradient through a ventilation mechanism.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Difference between respiratory bronchiole and terminal bronchiole? (4)

A

Respiratory bronchiole:
- Involved in gas exchange.
- Walls contain some alveoli, allowing for gas exchange.
- Less smooth muscle than terminal bronchiole, due to alveolar openings.
- Starts gas exchange due to alveoli presence.

Terminal bronchiole:
- Involved in air transport.
- No alveoli, completely lined with ciliated epithelium.
- More smooth muscle, helping regulate airflow.
- No gas exchange, only moves air.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of alveolar duct? (2)

A
  1. Continuation of the respiratory bronchiole.
  2. Serving as a passage to air reaching the alveoli.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Function of alveolar pores? (5)

A
  1. Allows air to move in between adjacent alveoli.
  2. Equalises air pressure.
  3. If bronchiole becomes blocked, alveolar pores provide alternate pathway for air to reach the lungs.
  4. Allows surfactant to move evenly across adjacent alveoli.
  5. Improves lung efficiency + compliance.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is surfactant? (7)

A
  1. Fluid (specialised phospholipid) secreted by septal cells in the alveolar wall.
  2. Fluid found in the liquid layer lining the alveolus.
  3. Reduces surface tension of water.
  4. Making it easier to inflate lungs.
  5. Prevents alveoli sticking together during exhalation.
  6. Contains anti-bacterial chemicals.
  7. Enables CO2 to dissolve into surfactant -> diffuse across alveolar wall but does not increase rate of diffusion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Outline how you go from trachea to alveoli.

A

Trachea (wind pipe) -> Bronchi (each one a bronchus) -> Bronchioles -> Alveoli.

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

Function of the pleural membrane? (3)

A
  1. Reduces friction -> contains pleural liquid -> lubricant -> allowing lungs to glide smoothly against chest wall during inhalation and exhalation.
  2. Prevents lungs collapsing -> maintains a sealed environment -> keeps lung surface attached to the chest wall.
  3. Connection with diaphragm ensures lungs expand + contract effectively during inhalation and exhalation.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Trachea - Specialisation and function? (4)

Study These Flashcards
A
  1. Carries air from the oral cavity to bronchi.
  2. It is held open by c-shaped rings of cartilage.
  3. Under the cartilage layer, there are smooth muscle, elastic fibres, glandular tissue, connective tissue, and blood vessels.
  4. Trachea lined with ciliated epithelial cells + goblet cells.
20
Q

Rings of cartilage -Specialisation and function? (3)

Study These Flashcards
A
  1. Found in the walls of trachea and bronchi.
  2. Provides support.
  3. Strong but flexible to prevent trachea and bronchi collapsing during inhalation + pressure drops.
21
Q

Bronchi - singular (BRONCHUS) - Specialisation and function? (3)

Study These Flashcards
A
  1. Base of the trachea.
  2. Each bronchus carries air into and out of the respective lung.
  3. Contains rings of cartillage for support + prevention of collapse during inhalation + pressure drops.
  4. Contains elastic fibres.
  5. Contains smooth muscle.
22
Q

Bronchioles - Specialisation and function? (4)

Study These Flashcards
A
  1. Subdivisons of bronchi.
  2. Walls of LARGER bronchioles contain smooth muscle, elastic fibres, goblet cells + ciliated epithelium.
  3. Walls of SMALLEST bronchioles contrain elastic fibres and epithelium (but NO CILIA).
23
Q

Alveoli - Specialisation and function? (6)

Study These Flashcards
A
  1. Blind ending sacs at the end of each bronchiole.
  2. Site of gas exchange.
  3. Diameter of 200-300 micrometers.
  4. Walls consist of single layer of squamous epithelial cells + elastic fibres containing elastin -> For stretch during inhalation and recoil during exhalation.
  5. Walls also contain collagen + stretch receptors -> Sensory input enable to control of ventilation mechanism.
  6. Liquid layer lining the alveolus contains surfactant.
24
Q

Goblet cells - Specialisation and function? (2)

Study These Flashcards
A
  1. Secrete mucus.
  2. Mucus traps microorganisms + dust + pollen.
25
What is mucus? (1)
1. Specialised glycoprotein -> Mucin + glycocalyx.
26
Cilia - Specialisation and function? (4)
1. Hair-LIKE extentions to the individual cells. 2. Beat and waft mucus in rhythmic motion. 3. Move mucus upwards towards throat + away from the lungs. 4. Move mucus + trapped pathogens up to the mouth to be swallowed -> HCI kills pathogens in the stomach or to be coughed up -> removed from body as sputum.
27
Elastic fibres - Specialisation and function? (4)
1. Found in walls of trachea, bronchi, bronchioles, and alveoli. 2. Inhalation -> elastic fibres in alveoli stretch to enable alveoli to inflate (NOT CONTRACT) -> Elastic fibres prevent the alveoli from bursting on over-inflation. 3. Exhalation -> Elastic fibres recoil to deflate alveoli. 4. Elastic fibres allow the lung TISSUE to expand and recoil.
28
Smooth muscle - Specialisation and function? (4)
1. Founds in walls of trachea, bronchi, and bronchioles. 2. Enables diameter to be controlled. 3. During exercise, smooth muscle relaxes -> lumen widens. 4. This reduces resistance to air flow -> easier to inhale and exhale.
29
Pulmonary ventilation? (5)
1. Consists of inspiration and expiration. 2. Maintains diffusion gradient. 3. Controlled by movement of diaphragm, internal + external interconstal muscles and ribcage. 4. Movement of fresh air into lungs and removal of stale air out of lungs. 5. Measured over a period of 1 minute.
30
Principle of pulmonary ventilation? (1)
1. Muscle contraction -> thorax moves -> changes in volume of thorax + lungs -> changes in pressure of lungs -> inspiration and exhalation.
31
Process of inspiration? (11)
1. External intercostal muscles contract. 2. Internal intercostal muscles relax. 3. Upwards and outwards movement of ribcage. 4. Diaphragm muscles contract. 5. Diaphragm flattens. 6. Volume of thorax increases. 7. Volume of lungs increases. 8. Pressure in lungs decreases. 9. Pressure in lungs is lower than the pressure outside of lungs. 10. Air rushes into lungs. 11. Active process - energy needed.
32
Process of expiration?
1. External intercostal muscles relax. 2. Internal intercostal muscles contract. 3. Ribcage movements downwards and inwards. 4. Diaphragm muscles relax. 5. Diaphragm dome-shaped. 6. Volume of thorax decreases. 7. Volume of lungs decreases. 8. Pressure in lungs increases. 9. Pressure in lungs is higher than the pressure outside of the lungs. 10. Air rushes out of lungs. 11. Passive process but forced exhalation is an active process -> Involves contraction of internal intercostal muscles.
33
Factors affecting lung capacity? (7)
1. Body size. 2. Gender. 3. Physical activity level. 4. General health. Approximately 6m^3 in adults. During normal breathing, much of this capacity is not used.
34
Tidal volume? (1)
1. Volume of air that moves in (hence out) in each normal breath - 0.5dm^3
35
Vital capacity? (1)
1. Maximum volume of air that can be inhaled or exhaled -> deepest forced exhalation after deepest forced inhalation -> 3-5dm^3
36
Residual volume? (1)
1. Volume of air that remains in the lungs after a forced exhalation -> Important as it prevents the lungs collapsing + alveoli from sticking together.
37
Breathing rate? (1)
1. Number of breaths taken in a given time period (usually one minute).
38
Equation for pulmonary ventilation? (1)
Tidal volume (dm^3) x breathing rate (min)
39
How is pulmonary ventilation assessed? (2)
1. Forced expiratory volume in one second (FEV1) = volume of air forcibly exhalaed in firs second of forced exhalation. 2. Peak expiratory flow rate (PEFR) = maximum rate of forced exhalation through mouth.
40
FEV1? (1)
1. Forced expiratory volume in one second (FEV1) = volume of air forcibly exhalaed in firs second of forced exhalation.
41
PEFR?
2. Peak expiratory flow rate (PEFR) = maximum rate of forced exhalation through mouth.
42
Normal values of PEFR? (5)
1. PEFR measurements used to diagnose pulmonary disorders -> asthma, chronic obstructive pulmonary disease. 2. Healthy adult male PEFR= 570-640 dm^3 min^-1 3. Healthy adult female PEFR = 420-460 dm^3 min^-1 4. PEFR increases with age for young child -> maximum value at age 30-35y. 5. PEFR decreases from age of 35 as a person ages to 85y.
43
Typical asthma values for males and females during episode reaction to allergen?
1. Males = 400 dm^3 min^-1 2. Females = 200 dm^3 min^-1
44
When does respiratory arrest occur?
1. When a person stops breathing.
45
Causes of respiratory arrest?
1. Obstruction blocking trachea or bronchi. 2. Drug overdose -> depresses nervous system and breathing system -> system stops. 3. Asthma attack. 4. Severe pneumonia. 5. Severe shock. 6. Heart attack.
46

Biology (7 decks)

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