BIOL113 L33

What are the functions of circulatory systems?

Mass transport of dissolved substances (O2, CO2, nutrients, hormones), transport of cells involved in defence and immunity, transport and dissipation of heat, transmission of force.

What are the two main types of circulatory systems?

Open circulatory systems and closed circulatory systems.

What is the main difference between open and closed circulatory systems?

Open circulatory systems have the circulatory fluid (hemolymph) directly bathing the organs, while closed circulatory systems have the blood confined to vessels.

What are aortic arches?

They are the main arteries in open circulatory systems that deliver blood to the body.

What are the advantages of closed circulatory systems over open circulatory systems?

Efficient delivery of oxygen and nutrients to tissues, better control of blood flow, and higher blood pressure.

What is a closed circulatory system?

A circulatory system where blood is contained within vessels and does not directly contact the body tissues.

What are the disadvantages of a closed circulatory system?

Higher energy expenditure and complexity compared to open circulatory systems.

What type of circulatory system do organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells likely to have?

a closed circulatory system

What is the function of arteries in the circulatory system?

Carry blood away from the heart, either oxygenated (systemic circuit) or deoxygenated (pulmonary circuit).

What are the characteristics of arterioles?

Arterioles are the finest branches of the arterial system, connecting arteries to capillaries. One of their key characteristics is the presence of smooth muscle in their walls. This smooth muscle allows arterioles to regulate blood flow to specific tissues and organs by constricting or dilating in response to local signals.

What are the characteristics of arteries ?

Arteries carry blood away from the heart – oxygenated (systemic circuit) or deoxygenated (pulmonary circuit) blood. They are thick-walled and elastic and smooth out pressure pulses of the beating heart.

what are characteristics of veins?

Veins carry blood towards the heart – oxygenated (pulmonary circuit) or deoxygenated (systemic circuit) blood. They are thin-walled – contain most of the blood. Veins in extremities contain valves to maintain direction of flow.

Describe the structure and function of capillaries in the circulatory system.

Capillaries are the finest vessels with thin permeable walls, serving as the site of gas and nutrient exchange with the tissues.

What is the role of venules in the circulatory system?

Venules are the smallest branches of veins that collect blood from capillaries.

In which of the following organisms does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body? annelids, fishes, frogs or insects

frogs

In vertebrates, why does a four-chambered heart deliver oxygen to the tissues more efficiently than a three-chambered heart?

Because a four-chambered heart can pump blood under high pressure

What is the correct sequence of blood flow in birds and mammals?
left ventricle → aorta → lungs → systemic circulation
vena cava → right atrium → right ventricle → pulmonary vein
pulmonary vein → left atrium → left ventricle → pulmonary circuit
vena cava → right atrium → right ventricle → pulmonary artery

vena cava - right atrium - right ventricle - pulmonary artery

What is the function of circulatory systems in animals?

Transport gases, nutrients, waste, hormones, and other substances around the body.

What is the major function of circulatory systems in most animals?

Oxygen transport.

What are the solutions for efficient oxygen transport in animals?

Separation of blood and body fluids, dedicated oxygen carriers (e.g. hemoglobin), separation of oxygenated and deoxygenated blood, double circuit to increase blood pressure through tissues.

What are the advantages of open circulatory systems?

Require much less energy to build and maintain.

What are the disadvantages of open circulatory systems?

Less efficient at delivering oxygen.