Physiology of the Circulatory System

The video explains blood pressure, focusing on systemic vascular resistance (SVR) and its role in the blood pressure equation. It covers how SVR is influenced by factors like vessel diameter, length, and blood viscosity. The sympathetic nervous system's impact on blood pressure through adrenaline is discussed, along with the renin-angiotensin system's role in long-term regulation. The video highlights the importance of understanding these concepts for managing cardiovascular health.

What is the primary function of blood pressure in the circulatory system?

• To transport oxygen to the lungs

• To exert force on blood vessel walls

• To digest food in the stomach

• To regulate body temperature

How does the diameter of arterioles affect blood flow?

• Diameter has no effect on resistance

• Smaller diameter increases resistance

• Smaller diameter decreases resistance

• Larger diameter increases resistance

What is the role of arterioles in systemic vascular resistance?

• They increase resistance by dilating

• They have no role in resistance

• They regulate resistance through muscle contraction

• They decrease resistance by constricting

What happens to your skin when the sympathetic nervous system is activated during stress?

• It becomes red and warm

• It turns pale due to constricted blood vessels

• It becomes itchy and dry

• It sweats excessively

How does the sympathetic nervous system affect the heart during a fight or flight response?

• It slows down the heart rate

• It decreases blood pressure

• It reduces cardiac output

• It increases heart rate and strength

Why does the heart need to pump harder in individuals with obesity?

• To increase body temperature

• To decrease blood viscosity

• To reduce blood vessel length

• To maintain blood pressure across longer vessels

What is the relationship between blood vessel length and blood pressure?

• Longer vessels decrease resistance

• Shorter vessels increase resistance

• Length has no effect on resistance

• Longer vessels increase resistance

What is the effect of increased blood viscosity on systemic vascular resistance?

• It decreases resistance

• It stabilizes resistance

• It has no effect on resistance

• It increases resistance

Which hormone is released by the kidneys to regulate blood pressure?

• Thyroxine

• Adrenaline

• Renin

• Insulin

What is the effect of polycythemia on blood viscosity?

• It stabilizes viscosity

• It has no effect on viscosity

• It increases viscosity

• It decreases viscosity