MCAT Respiratory system and the skin

Question 1

Tiny sacs, with walls only a single cell thick, found at the end of the respiratory bronchiole tree.

Answer 1

Alveoli

Question 2

___ are the site of gas exchange in the respiratory system

Answer 2

Alveoli

Question 3

Very small air tubes in the respiratory system. The walls of the __ are made of smooth muscle to help regulate air flows

Answer 3

Bronchioles

Question 4

Receptors in the central nervous system that monitor the pH of cerebrospinal fluid to help regulate ventilation rate.

Answer 4

Central chemoreceptors

Question 5

A layer of connective tissue underneath the epidermis of the skin

Answer 5

Dermis

Question 6

The __ contains blood vessels, lymphatic vessels, nerves, sensory receptors, and glands for the skin

Answer 6

Dermis

Question 7

The primary muscle of inspiration.

Answer 7

Diaphragm

Question 8

The __ is stimulated to contract at regular intervals by the respiratory center in the medulla oblongata (via the phrenic nerve). Although it is made of skeletal muscle ( and can therefore be voluntarily controlled), these stimulation’s occur autonomously

Answer 8

Diaphragm

Question 9

____states that the amount of gas that will dissolve into liquid is dependent on the partial pressure of that gas as well as the solubility of that gas in the liquid

Answer 9

Henry’s Law

Question 10

This is a layer of fat located under the dermis of the skin that helps to insulate the body and protects underlying muscles and other structures

Answer 10

Hypodermis

Question 11

What are the three main functions of the larynx?

Answer 11

1. Its rigidness ensures that the trachea is held open (provides an open airway)
2. The epiglottis folds down to seal the trachea during swalling, directs food to the esophagus
3. This is where the vocal cords are found (voice production

Question 12

___are receptors in the carotid arteries and the aorta that monitor blood pH to help regulate ventilation rate

Answer 12

Peripheral chemoreceptors

Question 13

The membranes that line the surface of the lungs (visceral pleura) and the inside wall of the chest cavity (parietal pleura)

Answer 13

Pleura

Question 14

The pressure in the space between the lung surface and the inner wall of the chest cavity.

Answer 14

Pleural pressure

Question 15

___ is negative with respect to atmospheric pressure; this keeps the lungs stuck to the chest cavity wall

Answer 15

Pleural pressure

Question 16

A collection of fluid in the alveoli of the lungs, particularly dangerous if it impedes gas exchange. Common cause are increased pulmonary blood pressure or infection in the respiratory system

Answer 16

Pulmonary edema

Question 17

A drop in blood pH due to HYPOVENTILATION and a resulting accumulation of CO2

Answer 17

Respiratory acidosis

Question 18

A rise in pH due to HYPERVENTILATION and a resulting decrease in CO2

Answer 18

Respiratory alkalosis

Question 19

An amphipathic molecule secreted by cells in the alveoli (type 2 alveolar cells) that reduces surface tension on the inside of the alveolar walls

Answer 19

Surfactant

Question 20

This prevents the alveoli from collapsing upon exhale and sticking together, thus reducing the effort required for inspiration

Answer 20

Surfactant

Question 21

___ cell secrete surfactant

Answer 21

Type 2 alveolar cells

Question 22

The part of the respiratory system designed only to allow gas to enter and exit the system is called the __

Answer 22

conduction zone

Question 23

Air pathway

Answer 23

Nose -> nasal cavity -> pharynx -> larynx -> trachea -> bronchi -> terminal bronchioles -> respiratory bronchioles -> alveolar ducts -> alveoli

Question 24

Why is there no gas exchange in the conduction zone?

Answer 24

The smooth muscle of the walls of the terminal bronchioles is too thick to allow adequate diffusion of gases

Question 25

From the nose all the way to the bronchioles, the epithelial cells are all___

Answer 25

tall columnar cells

Question 26

The ___, ___, and the ___ are involved in gas exchange

Answer 26

alveoli, alveolar ducts, and the smallest bronchioles

Question 27

___ reduces surface tension on the alveoli and helps them avoid collapsing

Answer 27

Surfactant

Question 28

Each lung is surrounded by two membranes

Answer 28

1. parietal pleura: lines inside of chest cavity

2. visceral pleura: lines the surface of the lungs

Question 29

What 6 steps occur during inspiration?

Answer 29

1. Diaphragm contracts and flattens (moves downward)
2. The volume of chest cavity expands
3. Pleural pressure decreases, becoming more negative
4. Lungs expand outward
5. Pressure in the alveoli become negative
6. Air enters lungs and the alveoli

Question 30

At the beginning of inspiration, the pleural pressure___

Answer 30

decreases, sucking the lungs open

Question 31

___ is the amount of air that moves in and out of the lungs with normal light breathing and is equal to about 10 percent of the total volume of the lungs

Answer 31

Tidal volume (TV)

Question 32

What are the principle chemical stimuli that affect ventilation rate?

Answer 32

Increased pCO2
decreased pH
decreased pO2

Question 33

____ are found in the medullary respiratory control center and monitor pCO2 and pH of the cerebrospinal fluid

Answer 33

Central chemoreceptors

Question 34

___ are located in the aorta and the carotid arteries and monitor the pCO2, pH, and pO2 of the blood

Answer 34

Peripheral chemoreceptors

Question 35

During an allergic attack ___ release histamine which causes bronchoconstriction

Answer 35

Mast cell

Question 36

___ does the opposite of histamine, it increases ventilation by causing airway smooth muscle to relax (bronchodilation)

Answer 36

Epinephrine

Question 37

The epidermis is composed of ___cells

Answer 37

stratified squamous epithelial cells

Question 38

Mitosis of epidermis cells occurs here and the newly divided cells move up towards the surface of the skin

Answer 38

Stratum basale

Question 39

__helps make the skin waterproof

Answer 39

KEratin

Question 40

___are sweat glands

Answer 40

Sudoriferous glands

Question 41

____ are oil glands in the skin

Answer 41

Sebaceous glands

Question 42

Sweat glands are responsive to the hormone__

Answer 42

aldosterone

Question 43

People living in hot climates must sweat alot, how does aldosterone help?

Answer 43

They have high amounts of aldosterone which helps conserve sodium, their sweat doesn’t waste alot of salt