Avian Cardiovascular and Respiratory System

What is the avian heart composed of?

Four chambers.

What is unique about the avian heart compared to mammals?

Larger relative to body size.

What is the function of the right ventricle in birds?

Pressurizes the pulmonary circulation.

What is the function of the left ventricle in birds?

Pressurizes the systemic circulation.

What are the main arteries supplying blood to the flight muscles?

Subclavian arteries.

What is the role of the vascular system in birds?

Delivers oxygen and nutrients to tissues.

What is a key adaptation of the avian vascular system?

Higher capillary density in flight muscles.

What are common sites for blood sampling in birds?

Jugular, brachial, and occipital veins.

What is the upper respiratory tract composed of?

Nasal cavity, sinuses, and upper larynx (glottis).

What is the function of the choana in birds?

Connects nasal cavity to oropharynx.

What is the syrinx in birds?

Lower larynx responsible for vocalization.

What is the trachea in birds?

A tube connecting the glottis to the syrinx.

What are the main components of the lower respiratory tract?

Lungs, air sacs, and bronchi.

What is the function of air sacs in birds?

Ventilates lungs unidirectionally.

What is unique about avian lungs?

Rigid and firmly attached to ribs and vertebrae.

What is the major advantage of the avian respiratory system?

Efficient gas exchange.

What are the major structures in the cranial coelomic cavity?

Heart, lungs, and air sacs.

How do avian adaptations predispose to respiratory diseases?

Susceptibility to airborne toxins.

What is a common cardiovascular disease in birds?

Atherosclerosis.

What is the significance of the renal portal system in birds?

Enhances nutrient absorption and detoxification.

What is the role of the avian heart in thermoregulation?

Helps conserve or remove body heat.

How does the avian respiratory system aid in thermoregulation?

Helps dissipate heat during flight.

What is the function of pneumatic bones in birds?

Lightens the skeleton and connects to air sacs.

What is unique about avian blood cells?

Nucleated red blood cells.

How does the avian cardiovascular system support high-altitude flight?

Increased capillary density and cardiac output.