TPR 12 - Respiratory System + Skin

Question 1

Which parts of glucose metabolism produce CO2, and what point in glucose metabolism utilizes oxygen?

Answer 1

Pyruvate dehydrogenase and the Krebs cycle produce CO2 during oxidative respiration, and O2 is reduced to water by the last e- carrier in the e-, cytochrome c oxidase.

Question 2

Ventilation versus respiration.

Answer 2

The simple movement of air into and out of lungs is properly called ventilation.

The actual exchange of gases b/t either lungs and the blood or blood and other tissues in the body.

Question 3

Conduction versus respiratory zone.

Answer 3

The parts of the respiratory sys that participate in actual gas exchange are referred to as the respiratory zone. The parts of the respiratory sys. that participates only in ventilation are referred to the conduction zone.

Question 4

pH regulation via the lungs.

Answer 4

In the blood, CO2 is converted to carbonic acid H2CO3 by RBC enzyme carbonic anhydrase. When CO2 is exhaled by the lungs, the amount of carbonic acid in the blood is decreased, as a result blood pH is increased and becomes more alkaline.

Question 5

Hyperventilation causes the pH of the blood to (increase/decrease), known as ____.

Answer 5

Hyperventilation causes the pH of the body to increase, known as respiratory alkalosis.

Question 6

Hypoventilation causes the pH of the blood to (increase/decrease), known as ___.

Answer 6

Hyperventilation causes the pH of the body to decrease known as respiratory acidosis.

Question 7

How does the lung provide thermoregulation.

Answer 7

Breathing can resultin significant heat loss - heat loss from the resp sys occurs through evaporative water loss, which functions under the same principles as sweating.

Question 8

How does panting increase heat loss.

Answer 8

The nasal passages warm and humidify the air entering the respiratory sys, and the exiting air is cooled and de-humidified. Breathing through the mouth will bypass this mechanism and increase the rate of heat loss.

Question 9

How does the respiratory sys. provide protection from disease and particular matter.

Answer 9

The mucociliary escalator and alveolar macrophages, discussed below, protect us from harmful inhaled particles.

Question 10

The pathway for inhaled air, starting with the nose.

Answer 10

Nose > nasal cavity > pharynx (throat) > larynx > trachea > bronchi > terminal bronchioles (final part of conduction> respiratory bronchioles > alveolar ducts > alveoli.

Question 11

The function of the nose.

Answer 11

The nose is important for warming, humidifying, and filtering inhaled air. Nasal hairs and sticky mucous acts as filters.

Question 12

Pharynx.

Answer 12

Common pathway for food and air. The throat.

Question 13

Three functions of the larynx (voice box)

Answer 13

1) made entirely of catrilage so keeps the airways open
2) contains the epiglottis, which seals the trachea during swallowing to prevent entry of food.
3) Contains the vocal cords for producing sound.

Question 14

The trachea branches into two ___.

Answer 14

Primary bronchi.

Question 15

The smallest and final branches of the conduction zone.

Answer 15

Terminal bronchioles.

Question 16

Aveoli.

Answer 16

TIny sacs witih very thin walls; the wall of these are one cell thick, except where capillaries pass across its outer surface.

Question 17

Difference b/t respiratory bronchiole and terminal bronhiole.

Answer 17

Both tubes are made of smooth muscle, but the respiatory bronchiole has a few alveoli scattered in its walls, so it participates in gas exchange.

Question 18

From the nose down to the bronchioles, the epithelial cells are ____. Do these participate in gas exchange? What is their function?

Answer 18

Tall columnar shaped cells. These cells don’t participate in gas exchange because they are too thick. Some of these cells are specialized to secrete a layer of thick mucus and are called globlet cells. The columnar epithelial cells of the upper resp tract have cilia on their surfaces which constantly sweep the laywer of mucus toward the pharynx, where mucus containing pathogens or inhaled particles can be swalloewed or coughed out, known as the mucociliary escalator.

Question 19

Mucociliary escalator.

Answer 19

The columnar epithelial cells of the upper resp tract have cilia on their surfaces which constantly sweep the laywer of mucus toward the pharynx, where mucus containing pathogens or inhaled particles can be swalloewed or coughed out, known as the mucociliary escalator.

Question 20

Types of cells the respiratory zones (alveoli, alveolar ducts, smallest bronchioles/respiratory bronchioles).

Answer 20

O2 and CO2 must be able to diffuse across the layer of epithelial cells in order to pass freely b/t bloodstream and the air in the lungs. Tall columnar cells with cilia would be too thick for rapid diffusion. Gas exchageing surfaces are lined with a single layer of thin, delicate SQUAMOUS (FLAT) epithelial cells.

Question 21

Surfactant.

Answer 21

A soapy substance that is a complex mixture of phospholipids, proteins, and ions secreted by cells in the alveolar wall. This reduces the surface tension of water layer in the alveoli to prevent collasp of it.

Question 22

Expiration versus inspiration.

Answer 22

Inspiration is the drawing of air into lungs. This is an ACTIVE process driven by the contraction of the diaphragm. Expiration is movement of air out of the lungs; passive expiration is driven by the elastic recoil of the lungs and doesn’t require active muscle contraction.

Question 23

The lungs aren’t directly connected to the chest wall. Each lung is surrounded by two membranes:

Answer 23

The PARIETAL PLEURA, which lines the inside of the chest cavity, and the VISCERAL PLEURA, which lines the surface of the lungs.

Question 24

Between the two pleura surrounding the lungs is a narrow space called the ___.

Answer 24

Pleural space.

Question 25

The pressure in the pleural space (the pleural pressure) is (negative/positive).

Answer 25

NEGATIVE.

Question 26

What happens if the pleural space is punctured, opening it to the external atmospher, what will occur?

Answer 26

The pleural space is always negative pressure, or the lung would collapse. If the pleural pressureis negative, and an opening to the atmosphere is made, then air will rush into the pleural space and the lung will collapse.

Question 27

What happens to the diaphragm during contraction and which muscles are involved.

Answer 27

When resting, the diaphragm is shaped like a dome. When it contracts, the diaphragm flattens and draws the cheset cavity downward, force it and the lungs to expand. The external intercostal muscles between the ribs also contract during inspiration, pulling the ribs upward and further expanding the chest cavity.

Question 28

During heavy exercise, contraction of ___ helps the expiration process by pressing upward on the diaphragm, further shrinking the size of the lungs and forcing more air out.

Answer 28

Contraction of the abdominal muscles.

Question 29

During inspiration, the following steps occur.

Answer 29

1) The diaphragm contracts and flattens out
2) The volume of the chest cavity expands
3) The pleural pressure decreases, become more negative
4) the lungs expand outward
5) The pressure in the alveoli becomes negative
6) Air enters the lungs and the alveoli.

Question 30

During expiration, the following steps occur.

Answer 30

1) The diaphragm relaxes and becomes a dome
2) The volume of the chest cavity decreases
3) The pleural pressure increases
4) The lungs shrink
5) the pressure in the alveoli becomes positive
6) Air enters leaves the lungs and alveoli

Question 31

When does alveolar pressure equal atmospheric pressure?

Answer 31

At the end of resting expiration, air tends to neither enter nor leave the lungs, until another inspiration begins. Just after inspiration, before expiration begins, there’s an instant of zero pressure.

Question 32

Spirometry.

Answer 32

The measurement of volume of air entering or exiting the lungs at the various stages of ventilation.

Question 33

Tidal volume.

Answer 33

The TV is the amount of air that moves in and out of the lungs with normal light breathing.

Question 34

Expiratory reserve volume.

Answer 34

The volume of air that can be expired after a passive resting expiration.

Question 35

Inspiratory reserve volume.

Answer 35

The volume of air that can be inspired after a relaxed inspiration.

Question 36

The functional reserve capcity.

Answer 36

The volume of air left in the lungs after a resting expriation.

Question 37

Inspiratoy capcity.

Answer 37

The maximal volume of air which can be inhaled after a resting expiration.

Question 38

Residual volume.

Answer 38

The amount of air that remains i the lungs after the strongest possible expiration.

Question 39

Vital capacity.

Answer 39

The maximum amount of air that can be forced out of the lungs after first taking the deepest possible breath.

Question 40

The total lung capcaity.

Answer 40

The vital capacity plus the residual volume.

Question 41

How can pulmonary edema form from left atrial increases in pressure?

Answer 41

If the pressure in the left atrium increases above a certain level, the pressure will increase in pulmonary capillaries, and fluid (especially blood plasma) will be forced out of the capillaries and into the surrounding lung tissue.

Question 42

How is CO2 carried in the blood?

Answer 42

Most is transported as HCO3- + H+; some is bound nonspecifically to Hgb, and a little can dissolve in plasma.

Question 43

Henry’s law.

Answer 43

According to Henry’s Law, the amount of gas that will dissolve into liquid is dependent on the partial pressure of that gas as well as the solubility of the gas in the liquid.

[O2] = PO2* SO2
O2 = the concentration of dissolved oxygen.
PO2 = partial pressure of O2 in the air above the fluid
SO2 = solublity of O2 in the fluid

Question 44

As pressure increases, gases become (more/less) soluable.

Answer 44

As pressure increases, gases become more soluable in liquid. Under great depths, gases dissolves into the blood and extracellular fluids more readily bc of the high pressure of the surrounding water.

Question 45

For diffusion to occur from air to the blood, gases must first pass by: __, __, and ___. These together form the respiratory epithelium.

Answer 45

Alveolar epithelium, interstistial liquid/space, and capillary endothelium.

Question 46

Although the partial pressure of O2 and N in the atmosphere are relatively constant, the partial pressure of water vapor can vary considerably. If water vapor in the atmosphere increases, what happens to O2 and N?

Answer 46

Total atm pressure is defined as the force exerted agianst a surface due to th eweight of the air above the surface. Thus, it is determined primarily by gravitational forces and changes very little. Partial pressure is defined as the portion of total pressure due to a particular gas; thus is the PH2O incresea, the total pressure still remains the same and thus O2 and N partial pressure will decrease.

Question 47

Although breathing can be voluntarily controlled for short periods of time, it is normally an involuntary process directed by the ____.

Answer 47

Respiratory control center.

Question 48

Name the two types of chemoreceptors that affects ventilation rate.

Answer 48

Peripheral - located in the aorta and carotid arteries and monitor the PCO2, pH, and PO2 of the blood.

Central - found in the medullary respiratory control center, and monitor PCO2 and pH of the CSF.

Question 49

What would cause the body to increase respiratory rate?

Answer 49

1) increase in PCO2, sensed by peripheral chemoreceptors and medulla
2) decrease in pH; increase in PCO2 causes decrease in pH via carbonic anhydrse; the decreased in pH is sensed by chemoreceptors.
3) decrease in PO2

Question 50

Epidermis, dermis and subcutaneous tissue/hypodermis.

Answer 50

The outermost layer of skin is called the epidermis. It lies upon the deeper dermis, which rests on subcutaneous tissues or hypodermis, a protective, insulating layer of fat.

Question 51

The epidermis is composed of layers of ___.

Answer 51

Stratified squamous cells.

Question 52

Stratum basale.

Answer 52

The cells are constantly sloughed off and then replenished by mitosis of cells at the deepest parts of the epidermis.

Question 53

How do cells become keratinized? What is the significance of this?

Answer 53

Well the strategy epidermis cells of the epidermis die, they become filled with a thick coating of tough, hydrophobic protein keratin.

Question 54

Function of melanin.

Answer 54

Epitehrlial cells contain melanin, produced by malenocytes. This is a brown pigment that absorbs UV light of the sun to prevent damage to underlying tissues.

Question 55

What is found in the dermis layer of the skin?

Answer 55

The dermis contains blood vessels, sensory receptors of touch, pressure, pain and temperature. Sweat glands, sebeaous glands, and hair follicles are found here.

Question 56

Does the epidermis contain blood vessels?

Answer 56

No.

Question 57

People who live in hot climates have high levels of aldoesterone. Why?

Answer 57

People living in hot conditions sweat a lot. In order to conseve sodium, they have a high level of aldoesterone, and thus their sweat does not waste salt (and conserve water).

Question 58

Homeotherms.

Answer 58

Homeotherms, like humans, have relatively cosntant body temperature.

Question 59

Four ways to cope with cold weather.

Answer 59

1) Contraction of skeltal muscles (shivering)
2) The skin insulates us so that we conserve heat generated by metabolism
3) Heat loss conduction is minimized by constriction of blood vessels in the dermis. Vasoconstrictino also happens when the SNS is activated. (Muscles, brain and heart vessels dilate) others constrict.
4) clothing, blankets helps us conserve heat.

Question 60

Two ways to cope with hot weather.

Answer 60

1) sweating allows heat loss via evaporation
2) dilation of blood vesels in the dermis results in heat loss by conduction or convection, which air blows past the skin.