Functions of the Blood Vessels

These flashcards cover key concepts related to the functions of the blood vessels, focusing on mechanisms of blood pressure regulation, capillary exchange processes, and relevant physiological responses.

What are baroreceptors?

Baroreceptors are sensors that detect changes in blood pressure.

What is the role of the medulla oblongata in blood pressure regulation?

The medulla oblongata processes information from baroreceptors and regulates blood pressure changes.

How does parasympathetic stimulation affect heart rate?

Parasympathetic stimulation decreases heart rate.

What happens during carotid sinus syncope?

Carotid sinus syncope occurs when baroreceptors misinterpret pressure increases, leading to a drop in blood pressure and fainting.

What hormones are involved in long-term blood pressure regulation?

The renin-angiotensin-aldosterone mechanism and antidiuretic hormone (ADH) are key hormones in long-term blood pressure regulation.

Why is hypertension referred to as 'essential'?

'Essential' hypertension historically implied high blood pressure was necessary for forcing blood through narrowed arteries, but this is a misconception.

What is the baroreceptor reflex?

The baroreceptor reflex is a rapid response mechanism that alters heart rate and vascular resistance in response to changes in blood pressure.

What main factors determine blood pressure?

Blood pressure is determined by cardiac output and systemic vascular resistance.

How do capillaries function as exchange vessels?

Capillaries exchange nutrients and waste between blood and tissues due to their thin walls and extensive surface area.

What three characteristics enhance capillary exchange?

Thin walls, large numbers, and slow blood flow through capillaries.

What is filtration in the context of capillary exchange?

Filtration is the process where pressure forces fluid and small substances out of capillaries into interstitial fluid.

What is the primary process of diffusion in capillaries?

Diffusion allows substances to move from higher to lower concentrations across the capillary walls.

What is oncotic pressure?

Oncotic pressure is the pressure exerted by plasma proteins in the capillaries that draws water back into them.

What causes edema in patients?

Edema can occur when filtration exceeds reabsorption, leading to excess fluid in interstitial spaces.

How does epinephrine affect blood pressure?

Epinephrine increases cardiac output and causes vasoconstriction, raising blood pressure.

What happens to blood flow during exercise?

During exercise, blood flow to skeletal muscles increases significantly to meet higher oxygen and nutrient demands.

What is the function of atrial natriuretic peptide (ANP)?

ANP lowers blood pressure by causing vasodilation and reducing blood volume.

What are the effects of sympathetic nervous system activation?

Activation of the sympathetic nervous system increases heart rate and blood pressure.

What is the role of the renal system in blood pressure regulation?

The renal system regulates blood volume and pressure through sodium and water balance.

What is the consequence of impaired lymphatic drainage?

Impaired lymphatic drainage can lead to fluid accumulation and edema.

How does stress impact blood pressure?

Stress can activate the sympathetic nervous system, increasing heart rate and blood pressure.

What is the difference between filtration and reabsorption in capillaries?

Filtration pushes substances out of capillaries, while reabsorption draws substances back in, mainly influenced by oncotic pressure.

What happens to capillary flow during vasodilation?

Vasodilation decreases resistance, allowing greater blood flow through capillaries.

How is cardiac output calculated?

Cardiac output is calculated by multiplying the stroke volume by the heart rate.

What is the significance of the blood pressure formula?

Blood pressure is calculated as the product of cardiac output and systemic vascular resistance.

What physiological process underlies the renin-angiotensin-aldosterone system?

It regulates blood pressure by controlling blood volume through fluid retention and vasoconstriction.