BIOL 2252: Respiratory System & Immune System UNIT 3

What structure divides the nasal cavity into right and left parts?

nasal septum

What is the largest cartilage in the larynx?

thyroid cartilage

What function besides lubrication does pleural fluid serve?

holds the visceral and parietal pleural membranes together

Which region is lined with pseudostratified ciliated columnar epithelium?

nasopharynx

What is the correct airflow order from bronchi to alveoli?

terminal bronchiole → respiratory bronchiole → alveolar duct → alveolus

According to Boyle's law, as volume increases, pressure…

decreases

During expiration, alveolar pressure is…

greater than barometric pressure

What happens to airflow during an asthma attack?

decreases

What happens to lungs during pneumothorax?

collapse

What is the function of surfactant?

decreases surface tension of alveolar fluid

If lung compliance increases, lung expansion is…

easier

Which lung capacity is the largest?

vital capacity

Which volume represents air available for gas exchange each minute?

alveolar ventilation

Which respiratory volume remains in lungs after forced expiration?

residual volume

What is the name of the muscle primarily responsible for breathing?

diaphragm

What structure prevents food from entering the trachea?

epiglottis

What is the function of the nasal conchae?

create turbulence in inhaled air

What tissue type lines alveoli for gas exchange?

simple squamous epithelium

What respiratory cells secrete surfactant?

type II alveolar cells (septal cells)

What is the function of alveolar macrophages?

remove debris and pathogens in alveoli

What part of the brain controls breathing rate?

medulla oblongata

Where is the respiratory control center located?

pons and medulla

What causes increased breathing rate during exercise?

increased CO₂ and hydrogen ion levels

What is the term for oxygen binding to hemoglobin?

oxygen loading

What enzyme facilitates CO₂ conversion in red blood cells?

carbonic anhydrase

Which direction does oxygen diffuse during gas exchange in lungs?

from alveoli to capillaries

Which immune system component is present at birth and nonspecific?

innate immunity

Which immune cell kills virus-infected and cancerous cells?

NK cells

What are the two main types of lymphocytes?

B cells and T cells

What protein messengers regulate immune activity?

cytokines

What is the function of interferons?

prevent viral replication in nearby cells

What organ is a primary lymphoid organ?

thymus

What is opsonization?

coating a pathogen to enhance phagocytosis

Which immune cell presents antigens to T cells?

dendritic cell

Which cell performs phagocytosis and is derived from monocytes?

macrophage

Which innate immune cells secrete histamine?

basophils and mast cells

Which line of defense involves skin and mucosal barriers?

first line of defense

Which line of defense involves fever and inflammation?

second line of defense

What is the term for programmed cell death initiated by NK cells?

apoptosis

What complement effect forms membrane pores in pathogens?

cytolysis

Which immune response is specific and slower to develop?

adaptive immunity

What is the role of helper T cells?

activate B cells and other immune cells

What do cytotoxic T cells do?

destroy infected or abnormal cells

What is the purpose of MHC molecules?

display antigens for recognition by T cells

What are antibodies produced by?

B cells (plasma cells)

Which antibody is the most abundant in blood?

IgG

Which antibody is found in secretions like saliva and tears?

IgA

What is the function of lymph nodes?

filter lymph and house immune cells

Which organ filters blood and recycles old red blood cells?

spleen

What is the function of the tonsils?

monitor pathogens entering through the mouth and nose

What is the effect of fever on pathogens?

inhibits growth and accelerates tissue repair

The majority of carbon dioxide is transported in plasma as:

bicarbonate ion

Which of the following statements about CO₂ is INCORRECT?

There is more CO₂ dissolved in the blood plasma than is carried in the RBCs.

The chemoreceptors in the aorta are most sensitive to changes in blood:

O₂ concentration

During normal breathing, what is the stimulus for increasing breathing rate and depth?

increased carbon dioxide levels in the blood

Why are the effects of CO₂ and H⁺ on breathing similar?

CO₂ combines with water to form H₂CO₃ which releases H⁺

The amount of oxygen released from hemoglobin increases:

all of the above:

during hypercapnia

when CO2 concentration increases

if pyrogens are released

if blood becomes more acidic

The dorsal and ventral respiratory groups are located in the:

medulla oblongata

The partial pressure of carbon dioxide at point D:

40 mmHg

The partial pressure of oxygen at point B:

104 mmHg

The partial pressure of carbon dioxide as blood comes in at point C:

45 mmHg

Cutting the phrenic nerve will result in:

Paralysis of the diaphragm

Which brain cell respiratory center is thought to generate the respiratory rhythm?

ventral respiratory group

The primary force responsible for air moving into the lungs during inhalation is:

atmospheric pressure

Even after the most forceful exhalation, a certain volume of air remains in the lungs. This volume is called the:

residual volume

The basic rhythm of breathing is controlled by which portion of the brain:

ventral respiratory group of the  medullary rhythmicity center

Within the blood, oxygen is primarily transported _________________ while the bulk of carbon dioxide is transported ____________________.

as oxyhemoglobin; as bicarbonate ions

Whether oxygen diffuses from the alveoli into the blood or not is dependent upon:

the partial pressure of oxygen in the lungs and in the blood

What is the first structure in the respiratory sequence?

pharynx

Which structures play the greatest role in warming and moistening air?

conchae

Which part of the respiratory tree has the greatest relative percentage of smooth muscle fibers?

bronchioles

What are the most powerful stimuli for breathing?

low pH; high CO₂

Which principle normally prevents the alveoli from collapsing during expiration?

secretion of surfactant

Alveolar cells that perform the function of phagocytosis are the

alveolar macrophages

As far as airflow is concerned, the rate of air flowing into the lungs is _______ related to the pressure gradient and _______ related to resistance.

directly; inversely

Why are the lungs able to stay inflated?

intrapleural pressure is exactly equal to intrapulmonary pressure.

As air travels through the respiratory tract, it travels from the pharynx to the _____ to the trachea?

Larnyx

Air that is inhaled has to go through a process called conditioning. Select the answer that is NOT part of the process that air goes through as it is inhaled.

The air is cooled.

• The air is humidified.

• The air is cleansed.

• The air is moistened.

• The air becomes turbulent.

The common name for the _______ is the voice box.

Larynx

What causes air to flow out of the body during expiration?

intrapulmonary pressure is greater than atmospheric pressure.

The pressure of a gas, according to Boyle's law, ______ if the volume of its container increases.

decreases

Oxygen can be carried bound to hemoglobin (in erythrocytes) or dissolved in plasma, approximately what percent of the oxygen in blood is transported by hemoglobin?

98%

The alveolar wall is made up of simple squamous cells referred to as

alveolar type I cell.

What keeps your trachea from collapsing?

The C-shaped cartilaginous rings

In regards to Gas volumes, the amount of air someone can forcibly inhale after a normal inspiration is

inspiratory reserve volume

Which one of the following region or regions of the respiratory tract is lined with pseudostratified ciliated columnar epithelium?

Nasopharynx

The conducting portion (zone) of the respiratory system consists of all of those

ЕХСЕРТ?

Alveoli

The respiratory membrane is where gas exchange occurs, which of the following IS NOT part of the respiratory membrane?

Plasma membrane of Type Il cell

• Capillary endothelium

• Plasma membrane of Type I cell

• Fused basement membrane

In the lungs, pulmonary gas exchange of oxygen is best described by which of the following statements?

Oxygen diffuses from the alveolus to the blood because the alveolus has a higher partial pressure of oxygen

The left lung and right lung differ from each other, what is NOT TRUE about the LEFT LUNG?

It has an esophageal depression.

• It has a cardiac notch.

• It has 2 lobes and 1 fissure.

• It has a cardiac impression.

• It is slightly smaller than the right lung.

The normal rate of breathing at rest is about _____ times per minute

12

The serous fluid of the lungs serves to?

lubricate and reduce friction between pleural membranes around the lung