Cardiovascular & Respiratory Systems

Homeotherms

organisms that maintain a relatively constant body temperature regardless of their surroundings

Pulmonary circulation

Circuit that delivers oxygenated blood from the right ventricle, to the pulmonary arteries, to the lungs, to the left atrium (Right heart - lungs - left heart)

Systemic circulation

Circuit that delivers oxygenated blood from the left ventricle, to the aorta, to the body, to the right atrium (Left heart - body - right heart)

Cardiovascular system

Carries oxygen (lungs), nutrients (bloodstream from intestine), and hormones to cells and in exchange remove CO2 and metabolic wastes from cells; maintains body temperature

Red blood cells

What cell in chicken blood is 1?

White blood cells

What cell in chicken blood is 2?

Thrombocytes

What cell in chicken blood is 3?

Right ventricle

Pumps blood to the lungs

Left ventricle

Pumps blood to the rest of the body

Venous system

carries deoxygenated blood from from the body to the heart

Arterial system

carries oxygenated blood from the heart to the body

Heart size

Increases with latitude and altitude; smaller birds have larger hearts

Plasma

light yellowish fluid containing water (~85%), dissolved minerals, electrolytes, lots of proteins (~11%), other nutrients, hormones, and waste products

Red blood cells (Erythrocytes)

large,elongated flat cells with oval nucleus; cannot change shape (cannot pass through capillaries)

Nucleated RBCs

Chicken RBCs

Not nucleated RBCs

Human RBCs

White blood cells (Leucocytes)

important in protecting birds from infectious agents (viruses and bacteria); include basophils, eosinophils, heterophils

Thrombocytes

nucleated; significant for blood clotting in chickens (human equivalent = platelets)

Heterophils

Poultry equivalent of neutrophils

Functions of blood

Moves O2 to body cells & removes CO2 from them, absorbs nutrients from the alimentary tract & transports them to tissues and cells, removes waste products of cellular metabolism; transports hormones produced by the endocrine glands to various sections of the body; helps regulate the water content of body tissues

Nares

usually located at the base of the beak; act as the passageway for air to be breathed in and out

Larynx

The entrance of the trachea; does not have vocal chords

Glottis

Opening of the larynx

Trachea

Formed by a series of ring-shaped cartilages (closed-in)

Syrinx (voice box)

Trachea bifurcates (divides) into bronchi after entering the thoracic cavity; produces sound for vocalization

Parabronchi

Tiny, inelastic lungs filled with tubular air capillaries; Movement of air is unidirectional through parabronchi, compared to dead-end structure of mammalian alveoli

Lungs

Only minimally expand and contract during inspiration and expiration; birds lack a diaphragm; act as organs in which gas exchange in the blood takes place

Air sacs

Recieving air during inspiration, acting as a cooling system since birds dont have sweat glands, for buoyancy, and defecation/egg-laying muscle assistance

Cervical

Air sacs in the neck region of poultry; help ventilate the neck and upper body, assist airflow, and act as air reservoirs during breathing; contain 2

Interclavicular

Air sac around the clavicle; help ventilate the humerus and wing bones and act as a central air distribution sac; contain 1

Anterior thoracic

Air sacs on the front of the thorax; help move air out of lungs, maintains continuous airflow throughout lungs, and reduces body density slightly; contain 2

Posterior thoracic

Air sacs on the rear thorax; primary air intake sacs and help drive unidirectional airflow through lungs; contain 2

Abdominal

Air sacs on the abdomen; largest air sac for expelling air from lungs; contain 2

Oxygen exchange

occurs on inspiration and expiration; 2-cycle pump; TWO inhalation /exhalation cycles required to move each breath totally through respiratory system; posterior air sacs to lungs to anterior air sacs