TAYLOR EXAM 3

What is the core function of the respiratory system?

To deliver oxygen to the body and remove carbon dioxide.

What are the four processes of respiration?

Pulmonary ventilation, external respiration, gas transport, and internal respiration.

What is pulmonary ventilation?

The movement of air into and out of the lungs.

What is external respiration?

Gas exchange between the alveoli and the blood.

What is gas transport?

The movement of oxygen and carbon dioxide through the blood between the lungs and body tissues.

What is internal respiration?

Gas exchange between the blood and body tissues

How do respiratory gases move through the body?

Down concentration gradients: O₂ moves air → blood → tissues, while CO₂ moves tissues → blood → air.

What are the two major zones of the respiratory system?

The conducting zone and the respiratory zone.

What is the respiratory zone?

The region containing alveoli and supporting tissues where gas exchange occurs.

What is the conducting zone?

Rigid, cartilaginous airways that conduct air to and from the lungs.

Why is cartilage important in the conducting zone?

it prevents airway collapse from pressure, body position changes, or external compression.

Why must the airways remain open?

To maintain uninterrupted airflow and breathing during different activities and positions.

What bones form the roof of the nasal cavity?

The sphenoid and ethmoid bones.

What bones form the floor of the nasal cavity?

The maxilla and palatine bones.

What are vibrissae?

Nasal hairs that trap debris near the entrance of the nasal cavity.

What are the three nasal conchae?

Superior, middle, and inferior conchae.

What is the function of the nasal conchae?

They increase surface area and create turbulent airflow to warm, moisten, and filter air.

Where is olfactory mucosa located, and what does it do?

it is located on the superior conchae and contains receptors for smell.

What is the function of respiratory mucosa?

It lines most of the nasal cavity and helps trigger protective reflexes such as sneezing.

Where are the paranasal sinuses located?

Within the frontal, ethmoid, sphenoid, and maxillary bones surrounding the nasal cavity.

What is the primary function of the paranasal sinuses?

To lighten the skull

Why is skull lightening important?

It helps reduce injury risk in infants and reduces neck strain in adults

What other functions do the paranasal sinuses have

They help warm and moisten inhaled air.

What causes a sinus headache when drainage is blocked?

Negative pressure caused by air being absorbed after sinus drainage is blocked

What type of water should be used in a neti pot?

Distilled water; tap water should never be used.

Why is proper sinus drainage important?

It helps prevent negative pressure, headaches, buildup of debris, and infections

What are the vocal cords?

Structures in the larynx consisting of true and false vocal cords, separated by the glottis.

What is the glottis?

The opening between the vocal cords; it opens during breathing and closes during swallowing and protective reflexes

What determines vocal pitch?

Vocal cord thickness, length, and tension. Thinner, shorter cords produce higher pitches; thicker, longer cords produce lower pitches

How does testosterone affect the voice during puberty?

It lengthens the vocal cords, causing the voice to deepen.

What determines vocal volume?

The amount of airflow passing through the vocal cords

What shapes speech sounds?

Articulation by the tongue, lips, and mouth, along with resonance from the oral cavity, nasal cavity, and sinuses

How does whispering occur?

Through articulation without vocal cord vibration

How can laryngitis affect speech?

Swollen or impaired vocal cords can cause loss of volume and a monotone voice

What is the Valsalva maneuver?

Closing the glottis while contracting abdominal muscles to increase internal abdominal pressure.

What is the Valsalva maneuver used for?

Defecation, core stabilization during heavy lifting, and temporarily altering blood pressure

How does the Valsalva maneuver help during heavy lifting?

It increases core rigidity, helping stabilize the spine and protect the back

How do infants use the Valsalva maneuver?

They instinctively use it during bowel movements to increase abdominal pressure

What effect can the Valsalva maneuver have on blood pressure?

It can temporarily raise and then lower blood pressure

What shape are the cartilage rings of the trachea?

C-shaped, incomplete rings

What closes the posterior gap in the tracheal cartilage rings?

The trachealis muscle

Why is the trachealis muscle important during swallowing?

It allows the esophagus to expand as large amounts of food pass through

How does the trachealis muscle help coughing?

ts contraction narrows the trachea and increases the force of expelled air

What is a tracheotomy?

an emergency procedure that creates an opening through the trachea to bypass an upper airway obstruction

Where is a tracheotomy performed?

Between the cartilage rings of the trachea

What nearby structure may be injured during a tracheotomy?

The thyroid gland, which can cause bleeding

What is the carina?

the point where the trachea divides into the primary bronchi; it is highly sensitive and triggers coughing

Why is the carina important?

sensitivity triggers a cough reflex to prevent foreign material from entering deeper lung tissue

What are the major branches of the bronchial tree?

Primary bronchi → secondary bronchi → tertiary bronchi → bronchioles → terminal bronchioles.

Why does the right lung have more secondary bronchi than the left?

The right lung has 3 lobes, while the left has 2 because of the heart's position

What happens to cartilage as airways branch smaller?

Cartilage decreases while smooth muscle increases

Why are bronchioles especially affected during asthma?

They lack cartilage and contain smooth muscle that can completely constrict during inflammation

How does the airway lining change as airways become smaller?

It transitions from pseudostratified columnar epithelium to cuboidal epithelium

What is the difference between bronchial and pulmonary circulation?

Bronchial circulation supplies lung tissues, while pulmonary circulation is responsible for gas exchange

Approximately how many alveoli are in the lungs?

about 300 million

Why are alveoli important for gas exchange?

They provide a large surface area—about 40 m²—for oxygen and carbon dioxide exchange.

What are Type I alveolar cells?

Thin cells that form the main diffusion surface for gas exchange

What are Type II alveolar cells?

Cells that produce surfactant to reduce surface tension and prevent alveolar collapse.

What is the air-blood barrier?

A very thin, one-cell-thick interface between alveoli and capillaries that allows efficient gas diffusion

What is the function of elastic fibers in alveoli?

They allow the alveoli to expand and recoil during breathing

What are alveolar pores used for

Equalizing pressure between neighboring alveoli

What do alveolar macrophages do?

Remove foreign particles and help keep the alveoli clean

What does surfactant do?

Reduces surface tension and prevents alveoli from collapsing during exhalation

Why can premature infants develop respiratory distress?

Their immature Type II cells may not produce enough surfactant, causing alveolar collapse.

What are the two layers of the pleura?

The parietal pleura and the visceral pleura

where is the parietal pleura located and what's its function?

parietal pleura lines the chest cavity

where is the visceral pleura located and what's its function?

the visceral pleura covers the lungs.

What is found between the two pleural layers?

A thin layer of pleural fluid.

What is the function of pleural fluid?

It reduces friction as the lungs move during breathing.

What is pleurisy?

inflammation of the pleural membrane

Why is pleurisy painful?

inflammation causes the pleural layers to swell and rub against each other, creating painful friction during breathing.

What can cause pleurisy?

Respiratory infections and other inflammatory conditions affecting the pleura

What are the major functions of cholesterol?

It is used to make plasma membranes, bile salts, and steroid hormones.

What is HDL?

High-density lipoprotein; it removes excess cholesterol from tissues and transports it to the liver. It is often called "good cholesterol."

What is LDL?

Low-density lipoprotein; it delivers cholesterol to body tissues and is associated with increased cardiovascular risk. "BAD cholesterol"

What is VLDL?

Very-low-density lipoprotein; it transports triglycerides for use as energy.

Why is the HDL-to-LDL ratio important?

better indicator of cardiovascular risk than total cholesterol alone.

Higher HDL is generally associated with?

lower heart attack risk.

What lifestyle factors can increase LDL?

Stress, cigarette smoking, and coffee consumption.

What can increase HDL?

Aerobic exercise and estrogen.

How does estrogen affect cardiovascular risk?

It raises HDL, giving premenopausal women some cardiovascular protection.

What happens to cardiovascular risk after menopause?

Lower estrogen levels reduce the HDL advantage, increasing cardiovascular risk.

How does body fat distribution relate to cholesterol?

Apple-shaped = higher cholesterol and LDL

pear-shaped = lower levels of cholesterol and LDL

Post-menopause where does women body fat shift?

toward the midsection

Why must excess amino acids be converted before being used for energy?

Amino acids cannot be stored directly in the body.

what happens to excess amino acids/proteins

get converted to energy

What are the three steps of amino acid metabolism for energy?

Transamination, oxidative deamination, and keto acid modification.

What occurs during transamination?

The amino group is transferred to a keto acid.

What occurs during oxidative deamination?

The amino group is removed as ammonia, which combines with CO₂ to form urea for excretion.

What happens during keto acid modification?

Keto acids are converted into intermediates that can enter the Krebs cycle.

what is Krebs cycle

second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions

When does increased amino acid breakdown occur?

During excessive protein intake, starvation, inadequate calorie intake, or poorly controlled diabetes.

What is nutrient interconversion?

The ability of the body to convert carbohydrates, fats, and proteins into different metabolic products.

In poorly managed diabetes mellitus what happens specifically with protein breakdown for energy?

when managed poorly the body will start to "eat itself"

How does Total Nutrient Supply exist

exists as interconnected pools with extensive sharing/conversion

Carbohydrates and fats have __ interconversion pathways and intermediates

numerous

Proteins have ____ interconversion pathways and intermediates

fewer

Which nutrients can be directly stored?

Carbohydrates as glycogen and fats as adipose tissue.

Can amino acids be stored directly?

No. Excess amino acids must first be converted into other compounds.

Most energy expenditure sustains basic life functions rathen than physical work?