bio 142 chapter 22 notes part 4

Where does external respiration occur?

Occurs between air in alveolus and pulmonary capillaries

Name the components of the respiratory membrane in the order that O₂ will cross during external respiration.  Keep in mind that CO₂ will pass in the opposite order.

Alveolar fluid (with surfactant → Alveolar epithelium→Epithelial basement membrane → interstitial space → Capillary basement membrane ^→ Capillary endothelium

Gasses will diffuse from areas of _____________ partial pressure to ____________ partial pressure. 

higher pressure to lower

In pulmonary capillary beds what will move from the capillaries to the alveoli.

carbon dioxide co2

what moves from he alveoli to the capillaries. 

oxygen o2

Where does internal respiration occur?

 between body tissues and systemic capillaries

1. In systemic capillary beds what will move from the capillaries to the tissues.

oxygen o2

what will move from the tissues to the capillaries. 

co2

 How is O₂ transported through the blood?

 attached to hemoglobin

What chemical components make up a hemoglobin molecule?

2 alpha + 2 beta and 4 heme groups

What do you call a hemoglobin molecule that is fully saturated with O₂?

oxyhemoglobin

What do you call a hemoglobin molecule that is not fully saturated with O₂?

deoxyhemoglobin

blood ARRIVING to alveolar capillaries has what type of PO2

Low po2

blood ARRIVING to alveolar capillaries has what type of PCO2

High compared to air inside alveoli

 Blood arriving to the systemic capillaries has a PO2

HIGH po2

 Blood arriving to the systemic capillaries has a PCO2

LOW PCO2 compared to interstitial fluid

What body conditions result in a decreased affinity between O2 and hemoglobin?

increased co2 levels (Hypercapnia)

decrease PH / Increase H+ (acidity)

Increased temperature

Increased 2,3-BPG

increased co2 levels (Hypercapnia)

Cellular respiration consumes oxygen and produces carbon dioxide as waste.

SO THIS MEANS IN THIS CONDITION

High carbon in tissue so tissue is metabolically hyperactive and desperately needs oxygen to keep going

decrease PH / Increase H+ (acidity)

As CO2 builds up, it reacts to form carbonic acid, (RELEASES HYDROGEN ION)

SO IN THIS CONDITION

heavily working muscles may produce lactic acid via anaerobic respiration.

WHICH MEANS

High acidity indicates the tissue is working past its normal limit.

Increased Temperature

Metabolic reactions produce heat. A muscle group that is actively contracting and burning energy will be noticeably warmer than resting tissue,

high demand for oxygen

Increased 2,3-BPG

metabolic byproduct produced by red blood cells during glycolysis.

SO

levels of 2,3 BPG rise due to chronic low oxygen environment (LIKE HIGH ALTITUDE) OR intense exercise

WHICH forces hemoglobin to unload more O2

1. What body conditions result in an increased affinity between O₂ and hemoglobin?

decreased co2 levels (Hyporcapnia)

increased PH / decreased H+ (alkalinity)

Decreased Temperature

Decreased 2,3-BPG

decreased co2 levels (Hyporcapnia)

Low co2 = means cells are at rest and not generating much metabolic waste.

WHICH MEANS

since tissue does not burn energy no extra oxygen needed

increased PH / decreased H+ (alkalinity)

Lack of co2 and lactic acid means less hydrogen ions present

SO THIS MEANS

higher alkaline pH signals that the tissue is relaxed and operating well within its resting metabolic limits.

Decreased 2,3-BPG

When metabolic rates drop, red blood cells produce less 2,3-BPG

SO

without molecule pushing oxygen off the hemoglobin,

Decreased Temperaturethe hemoglobin hangs onto its oxygen cargo much more tightly.

Decreased Temperature

Resting tissues do not generate excess heat from metabolic reactions

SO

cooler temperature signal to hemoglobin that the surrounding area is quiet and doesn't need oxygen

68. How much O2 is still in venous blood when it returns to the lungs? Why?

75% saturated with oxygen

at rest, your body's cells only require about 25% of the oxygen carried by the blood.

What are the three methods by which CO2 is transported though the blood?

carbonionhembolgobin 20%

bicarbonate 70%

plasma 10%

70. What do you call a hemoglobin molecule that has combined with CO2?

carbaminohemoglobin

CO2 moves into the blood it combines with water in the following reaction:

co2 + h2o → H2CO3 but this causes H+ + HCO-3

what does the h+ combine with and why

H+ combines with hemoglobin to prevent blood from becoming acidic

As the blood arrive as the lungs the equation reverses allowing CO2 to exit the blood

H+ + HCO-3 → H2Co3 → CO2 + h2o

72. What happens to the following with age? cilia

less active

72. What happens to the following with age? mucus

thicker

72. What happens to the following with age?Swallow, cough, gag reflex

slowing down

72. What happens to the following with age?Macrophages

lose efficiency

72. What happens to the following with age? bronchial walls

thinner and collapse

72. What happens to the following with age? dead space

increases

72. What happens to the following with age?g. Alveolar capillaries:

Decreased density and number

What 3 microscopic layers make up the respiratory membrane?

1. Type I Alveolar Cells (squamous epithelium)

2. Fused Basement Membrane

3. Capillary Endothelium

By what specific transport mechanism do o2 and co2 ross the respiratory membrane?

Simple passive diffusion

partial pressure gradients of o2 between the alveoli and deoxygenated blood.

o2 steep gradient of 104mmHG (alveolus) vs 40mmHG (blood)

partial pressure gradients of co2 between the alveoli and deoxygenated blood.

co2 has a gentle gradient 45mmHg (blood) vs 4o mmHg (alvelous)

how does co2 diffuse as fast as oxygen regarding the 5 mmHG difference

co2 is 20x more soluble in liquid and plasma membranes than oxygen,

How do Emphysema structurally disrupt gas exchange?

Destroys alveoli walls, which decreases surface area.

how do Destroys alveoli walls, which decreases surface area.

Causes fluid buildup, which increases membrane thickness.

Define Ventilation-Perfusion Coupling.

physiological matching of airflow (ventilation) to blood flow (perfusion) in the lungs.