Respiratory, Digestive, and Immune System Anatomy & Physiology Review

List the types of T cells.

Helper (CD4/TH), cytotoxic (CD8/TC), regulatory (TR), and memory (TM).

List the factors that influence ventilation.

Airway resistance, alveolar surface tension, and lung compliance.

Define intrapulmonary pressure.

Pressure within the alveoli.

How is the volume of the pleural cavity increased?

The diaphragm contracts and flattens, and external intercostal muscles lift the ribs, enlarging the thoracic cavity.

What does the Haldane effect explain?

Removing oxygen from hemoglobin increases its ability to bind carbon dioxide and carbon dioxide-generated hydrogen ions at the tissues.

What is the function of the bronchopulmonary segment?

A section of lung supplied by its own tertiary bronchus. Its airways deliver air to alveoli for gas exchange.

Which leukocyte secretes heparin?

Basophils.

Define antigen.

A substance that mobilizes the immune system and provokes an immune response.

What force drives the exchange of oxygen and carbon dioxide?

Diffusion which is powered by Partial pressure gradients.

What is the function of surfactant?

Reduces alveolar surface tension, preventing collapse and making the lungs easier to inflate.

Why does air rush into your lungs when you inhale?

Muscle contraction increases intrapulmonary volume, lowering pressure so air flows into the lungs.

List the things that can weaken the bond between hemoglobin and oxygen.

Increased temperature, increased PCO2, increased hydrogen ion concentration, and increased BPG.

Explain how MHC class I proteins are made.

A base protein combines with a fragment of a self protein or a foreign product made inside the cell, such as a viral protein.

What is found posterior to the epiglottis?

The laryngopharynx.

Which layer of the nasal mucosa contains extensive venous networks?

The lamina propria.

How can a CD4 cell be activated?

Its antigen receptor binds an antigen-MHC class II complex on an antigen-presenting cell. Costimulation from other surface receptors or cytokines is required for full activation.

How many secondary bronchi branch from the left bronchus?

Two, corresponding to the left lung's two lobes.

What is the function of type II cells in the alveolus?

Secrete surfactant.

Which kind of epithelium is found in the walls of the alveoli?

Simple squamous epithelium, formed mainly by type I alveolar cells.

Where do T cells mature?

In the thymus.

What creates the greatest resistance to airflow in the lungs?

When airway diameter decreases, which is common in medium-sized bronchioles ( Lobular Bronchioles)

T cells cannot become fully activated without what?

Costimulation.

What is the primary generator of respiratory rhythm?

The ventral respiratory group (VRG).

Secondary bronchi are also referred to as what?

Lobar bronchi.

What will cause lungs to collapse?

Any condition that equalizes intrapulmonary and intrapleural pressures.

What effect will a high PCO2 have on the lungs?

In poorly ventilated areas, airways dilate and pulmonary capillaries constrict. CO2 retention also increases breathing rate and depth.

What does Boyle's law explain?

Gas pressure varies inversely with volume: increasing volume decreases pressure, and decreasing volume increases pressure.

List the things believed to affect breathing during exercise.

Conscious anticipation of exercise, simultaneous cortical motor activation of skeletal muscles, and excitatory impulses from proprioceptors to respiratory centers.

What things combine to make carbon dioxide when blood reaches the lungs?

Hydrogen ions and bicarbonate ions combine to form carbonic acid, which becomes carbon dioxide and water.

What is the name of the lung surface that contacts the thorax?

Costal surface.

Explain how negative selection of T lymphocytes works and what it produces.

Cells that attack self MHC proteins are deleted or become unresponsive through anergy. Weakly interacting cells mature, producing T cells with immunocompetence and self-tolerance.

Where is the cardiac notch located?

In the left lung, where it accommodates the heart.

What is the term for normal breathing in and out?

Eupnea (ventalation)

Which structures branch from respiratory bronchioles?

Alveolar ducts.

Which cells have MHC class II proteins?

mature B cells, CD4 cells, and antigen-presenting cells.

Which cells secrete pepsinogen?

Chief cells.

What is inhibited when acidic chyme reaches the duodenum?

Vagal nuclei and local reflexes are inhibited. Sympathetic fibers also activate, constricting the pyloric sphincter.

Which chemicals initiate ion pumping from parietal cells into the stomach lumen?

Gastrin, acetylcholine, and histamine stimulate HCl secretion. Gastrin and acetylcholine increase calcium permeability; histamine acts through cyclic AMP.

Where are G cells located?

In the stomach's antrum. Also among cells in fundic glands.

What do terminal branches of neurons synapse with in multiunit smooth muscle?

Individual smooth muscle cells, creating motor units.

What is the term for swellings on autonomic fibers containing neurotransmitter vesicles?

Varicosities.

Which cells secrete serotonin in the stomach?

Enteroendocrine cells, labeled G cells

In which intestinal layer would you find blood vessels?

Submucosa contains the larger blood vessels. Capillaries are also found in the mucosa's lamina propria.

What is the term for folds in the mucosa of the small intestine?

Circular folds, also called plicae circulares, formed by the mucosa and submucosa.

During the gastric phase, what inhibits gastrin release?

High stomach acidity.

During fat absorption, where are triglycerides combined with phospholipids and cholesterol?

In the Golgi apparatus, forming chylomicrons.

What stimulates the gastric phase of secretion?

Stomach distension, peptides, and high pH.

What is it called when an antibody blocks a specific site on a virus?

Neutralization.

Which antibody accounts for 80% of antibodies circulating in blood plasma?

IgG.

List the specific roles of helper or CD4 cells.

Stimulate proliferation and cloning of antigen-bound T and B cells, stimulate activated B cells to divide and produce antibodies, interact directly with B cells to stimulate them, and mobilize cytotoxic CD8 cells.