Final Exam Study Guide from Studco

Respiration is the exchange of gases between which of the following, blood, cells, and atmosphere?

between atmosphere and blood and between blood and cells

How do the cardiovascular and respiratory system cooperate?

CV transports gases in blood

What three processes are required for respiration and what exchanges happen in each process?

• pulmonary ventilation: breathing; exchange of air between atomsphere and alveoli

• external (pulmonary respiration): exchange of gas between alveoli and blood in pulmonary capillaries

• internal (tissue) respiration: exchange of gas between systemic capillaries and tissue cells

Describe the cartilaginous framework of the nose

• bone and hyaline cartilage is joined by fibrous connective tissue and lined with mucous membrane

What are the three functions of the internal structures of the external nose?

• warm, moisten, and filter incoming air

What are the layers of the tracheal wall from deep to superficial?

mucosa, submucosa, hyaline cartilage, layer of areolar connective tissue

Describe the components of the trachea

• mucosa has epithelial layer of ciliated pseudostratisfied columnar epithelium

• surrounded by incomplete rings of hyaline cartilage which allows for subtle changes during breathing

Describe the branching of the bronchial tree as well as the zone these structures are a part of and the composition of these structures

1. trachea branches into right and left primary bronchus

2. conducting zone:

• main bronchi: pseudostratified ciliated columnar epithelium, goblet cells

• lobar bronchi: pseudostratified ciliated columnar epithelium, goblet cells, plates of cartilage

• segmental bronchi: pseudostratified ciliated columnar epithelium, goblet cells, reduced cartilage

• bronchioles: ciliated simple columnar, more smooth muscle

• terminal bronchioles: ciliated simple cuboidal epithelium, minimal cartilage, increased smooth muscle

3. respiratory zone:

• respiratory bronchioles: simple cuboidal to simple squamous

• alveolar ducts: simple squamous

• alveolar sacs: simple squamous

• nasopharynx: air only; ciliated pseudostratified columnar epithelium

• oropharynx: respiratory and digestive; stratified squamous epithelium

• pulmonary arteries

What is each lobule wrapped in?

connective tissue and contains a lymphatic vessel, arteriole and venule

From the alveolar air space to the blood plasma the respiratory membrane is composed of

• layer of type 1 and 2 alveolar cells and associated alveolar macrophages that constitutes the alveolar wall

• epithelial basement membrane underlying the alveolar wall

• capillary basement membrane often fused to epithelial basement membrane

• capillary endothelium

____ easily diffuses into the blood while __ diffuses into the alveoli

CO2, O2

Describe respiration in steps

1. Ventilation: Air is drawn into the lungs (inhalation) and expelled (exhalation).

2. External respiration: Gas exchange occurs between alveolar air and blood in the capillaries.

3. Transport: Oxygen is carried by blood to tissues, while carbon dioxide is transported back to the lungs.

4. Internal respiration: Gas exchange occurs between blood and body tissues.

What is the rate of airflow and effort needed for breathing influenced by?

• alveolar surface tension

• compliance of lungs and airway resistance

Inhalation muscles and action

• contract diaphragm and external intercostals

• forced: scalenes and SCM

Exhalation muscles and action

• relaxed diaphragm and external intercostals

• forced: internal intercostals and abdominal muscles contract to push air out.

Describe factors affecting pulmonary ventilation

• surface tension: as inward direction force in the alveoli it must be overcome to expand the lungs —> surfactant helps

• elastic recoil: decreases the site of the alveoli during expiration

• compliance: ease with which lungs and thoracic wall can be expanded

• airway resistance: narrowing of airway

Discuss how Dalton’s Law applies to respiration

• each gas exerts its own partial pressure

• this determines how O2 and CO2 move between lungs and blood

Discuss how Henry’s Law applies to respiration

• amount of gas that will dissolve in a liquid has to do with a partial pressure and solubility

External Respiration

• O2 diffuse from alveoli into pulmonary capillaries and CO2 move opposite

• This gas exchange occurs due to differences in partial pressures, following Dalton's Law, allowing O2 to enter the bloodstream and CO2 to be expelled.

Internal Respiration

• O2 diffuse from systemic capillaries to tissues and CO2 moves opposite

• This process involves gas exchange at the cellular level, driven by differences in partial pressures of O2 and CO2, facilitating oxygen delivery to tissues and carbon dioxide removal.

What are factors affecting the rate of gas exchange?

• partial pressure differences of gases

• Surface area available for gas exchange

• diffusion distance

• molecular weight and solubility

O2 where its dissolved and how it is carried

• 1.5% dissolved in plasma

• 98.5% carried by hemoglobin in red blood cells.

CO2 where its dissolved and how it is carried

• 7% dissolved in plasma

• 23% carried by hemoglobin as carbaminohemoglobin

• 70% transported as HCO3

Describe the factors affecting the affinity of hemoglobin for O2

• PO2: partial pressure between Hb and PO2; high PO2 = greater binding with Hb

• pH: high blood ph = more saturated so low blood PCO2

• temp: high temp = less saturated Hb with O2 which causes the release of O2 more readily and less affinity

Describe the control of respiration using receptors, control centre and effectors

• condition: high arterial blood PCO2 and low pH and PO2

• central chemoreceptors in medulla and peripheral in aortic and carotid bodies sense this and send nerve impulses to DRG in medulla oblongata causing inhale and exhale muscles to contract more forcefully and frequently (hyperventilation)

• result: lowered arterial blood PCO2, increase pH and PO2