Anatomy lab practical: respiratory system

What is the upper division of the respiratory tract?

structures found in the head and neck

What is the upper division of the respiratory tract?

larynx and the structures below

Three functions of the nasal cavity

Filters, warms, and moistens incoming air, resonating chamber for voice, smell

Included structures of the nasal cavity

external nares (nostrils), conchaes, sinuses

Pharynx function

Connects nasal and oral cavities to larynx and esophagus

3 regions of pharynx

nasopharynx, oropharynx, laryngopharynx

Nasopharynx is only involved in ____

respiration

Oropharynx is the middle region from ___ to ___

soft palette, epiglottis

Functions of oropharynx and laryngopharynx

Respiratory and digestive functions

Laryngopharynx is the most inferior region, from ___ to ___

epiglottis, larynx

Functions of larynx

prevents food/fluid from entering the lungs, permits the passage of air and produces sound

What structures in the larynx made of

cartilaginous and membranous structures

Thyroid cartilage (hyaline) function

Forms the framework of the larynx, Contains the laryngeal prominence (Adam’s apple)

cricoid cartilage (hyaline)

attaches the larynx to the trachea

arytenoid cartilage (hyaline) function

anchors the vocal folds

epiglottis (elastic) function

closes the opening of the trachea during swallowing

vocal folds (true vocal cords) function and structure

vibrate with expired air to produce sounds, made of elastic fibers covered with mucous membrane

vestibular folds (false vocal cords) function and structure

protect the vocal folds, made of elastic fibers covered with mucous membrane

Glottis function

Slit-like passageway between the folds

Trachea function

connects larynx to bronchi

Trachea walls are reinforced with _____. This _____ during swallowing, and helps maintain an ____.

C-rings of hyaline cartilage, allows expansion, open airway

What tissue is the trachea lined with?

Pseudostratified ciliated columnar epithelium

What cells produce mucus for the trachea lining?

goblet cells

Function of cilia on the trachea

Moves mucus away from lungs and to throat

What are bronchi?

A series of branching respiratory tubes

What is the full airflow pathway from trachea to gas exchange?

Trachea → (left/right) Primary bronchi → Secondary bronchi → Tertiary bronchi → Terminal bronchioles → Respiratory bronchioles → Alveolar ducts → Alveolar sacs

What are alveolar sacs?

Clusters of alveoli

What are alveoli?

balloon-like pockets at the end of alveolar ducts

What forms the respiratory membrane(blood air barrier)?

Alveolar and capillary walls with their fused basement membranes

Alveoli are sites of ____, which occurs by ____.

gas exchange, simple diffusion

What are alveoli densely covered with?

pulmonary capillaries

What are alveoli composed of?

A single layer of simple squamous epithelium overlying a basal lamina

Lungs are made mostly of ___. Some ____ allows for expansion and contraction.

Respiratory passageways, Elastic CT

Lungs fill the entire ___, except for the ___.

thoracic cavity, mediastinum

What is the cardiac notch?

concavity of left lung that provides space for the heart

Each lung is divided by ____ into multiple lobes.

fissures

How many lungs for the left lobe have? The right?

2 and 3

What is the pleurae?

Double-layered serous membranes surrounding each lung

Parietal pleura- ___ layer, attach to ___ and the ____

outer, thoracic walls, diaphragm

Visceral pleura- ____ layer, covering the ____ of the lung

inner, external surface

During inspiration…

• inspiratory muscles ___

• thoracic cavity ___ in size

• intrapulmonary volume ___

• intrapulmonary pressure ___

• air flows to the area of ____ pressure (into the ____)

contract, increases, increases, decreases, lowest, lungs

During inspiration…

• inspiratory muscles ___

• thoracic cavity ___ in size

• intrapulmonary volume ___

• intrapulmonary pressure ___

• air flows to the area of ____ pressure (out of the ____)

relax, decreases, decreases, increases, lowest, lungs

Should you breathe in through the spirometer?

No

Can dry spirometers measure the volume of air inspired?

No

Can wet spirometers measure inspired air?

ONLY some

What does a spirometer record?

The volume of air expired

What are bronchial sounds produced by?

air rushing through the large respiratory passageways (trachea and bronchi)

What are vesicular sounds produced by?

Air filling the alveolar sacs, sounds like rusting leaves

What can respiratory sounds be ausculated by?

stethoscope

Respiratory diseases produce abnormal sounds. Provide examples.

Diseased tissue, mucus or pus

What are obstructive respiratory diseases caused by? provide examples

Increased resistance in airways. there is normal vital capacity, but decreased rate of air flow due to bronchoconstriction. Asthma, chronic bronchitis

What are restrictive respiratory diseases caused by? provide examples

Lung capacity declines, vital capacity decreases. Polio, tuberculosis

What is forced vital capacity (FVC)?

Volume of air exhaled after a maximal inhale followed by a forceful, rapid exhale

In what condition is FVC reduced?

Restrictive pulmonary diseases

What is forced expiratory volume (FEVₜ)?

The percentage of vital capacity that is exhaled during specific time intervals

What is FEV₁?

Volume of air exhaled in the first second of forced exhalation

What % of FVC is normally exhaled in the first second?

75–85%

In what condition is FEV reduced?

Obstructive pulmonary diseases

What controls respiratory rhythm and rate?

Neural centers in the medulla and pons

What can suppress respiratory centers?

Sleeping pills overdose or high alcohol intake

What is the normal respiratory rate?

12–18 respirations per minute

What physical factors affect respiration?

Talking, yawning, coughing, exercise

What chemical factors affect respiration?

O₂ levels, CO₂ levels, and pH

How is blood pH regulated in respiration?

Carbonic acid–bicarbonate buffer system

What is normal arterial blood pH?

7.4 ± 0.02

What diffuses the blood from tissues to start the buffer system?

CO₂

What reaction forms carbonic acid? Which enzyme is this facilitated by?

CO₂ + H₂O → H₂CO₃ , carbonic anhydrase

What does carbonic acid break into?

H₂CO₃ - → H⁺ + HCO₃⁻ (bicarbonate)

How is the H⁺ from the bicarbonate buffer system neutralized?

it attaches onto hemoglobin

What happens to bicarbonate (HCO₃⁻) after it is formed?

It moves into plasma down its concentration gradient

How is negative charge balanced when HCO₃⁻ leaves the RBC?

Cl- is drawn from plasma INTO RBC (chloride shift)

What happens when blood pH decreases?

H⁺ binds HCO₃⁻ (bicarbonate ion) → H₂CO₃ (carbonic acid). This removes free H+

What happens when blood pH increases (↓ H⁺)?

H₂CO₃ (carbonic acid) → H⁺ + HCO₃⁻ (bicarbonate ions). This releases free H+

During hyperventilation:

CO₂ ______

Carbonic acid (H₂CO₃) ______

H⁺ ______

pH ______ → respiratory ______

decreases, decreases, decreases, increases, alkalosis

During hypoventilation:

CO₂ ______

Carbonic acid (H₂CO₃) ______

H⁺ ______

pH ______ → respiratory ______

increases, increases, increases, decreases, acidosis