Overview of Sensory Receptors and Blood Circulation

Free nerve endings

Simplest sensory receptors

Adaptation

The decrease in sensation during a long stimulus

Somatic senses

Touch, pressure, pain, and itch

Special senses

Vision, hearing, taste, smell and equilibrium

Classification of receptors

Chemoreceptors, mechanoreceptors (pressure), photoreceptors, thermoreceptors

Referred pain

Pain that originates inside the body but is felt outside the body

Proprioception

The body's ability to sense its position, movement, and orientation in space without relying on visual input

Lysozyme

An enzyme that destroys bacteria

Sclera

White of the eye

Retina

Where the photoreceptors are

Ciliary muscle

Holds the lens

Fovea centralis

Area with sharpest vision

Glaucoma

A buildup of pressure in the eye that leads to blindness; most common cause of blindness

Homeostasis coordination systems

Nervous system and endocrine system

Endocrine glands

Pituitary, thyroid, adrenal, pancreas, ovaries/testes

Exocrine glands

Glands that secrete substances through ducts

cAMP

Cyclic AMP; Second messenger system

Insulin and glucagon relationship

Insulin lowers blood glucose levels, glucagon raises blood glucose

PTH & calcitonin relationship

Parathyroid hormone raises blood calcium levels, calcitonin lowers blood calcium levels

Alpha cells

Produce glucagon in pancreas

Beta cells

Produce insulin in pancreas

Calcitonin

Produced by the thyroid gland

PTH

Produced by the parathyroid gland

Thyroxine

Produced by follicular cells of the thyroid gland

Anterior pituitary hormones

Growth hormone (bone and muscles), prolactin (milk production), follicle-stimulating hormone and luteinizing hormone (testes or ovaries), thyrotropic (metabolism), ACTH (adrenal cortex), MSH (melanin stimulating hormone, make skin darker)

Posterior pituitary hormones

Oxytocin (child birth, uterine contractions) and ADH (kidney tubules to raise blood pressure)

Functions of blood

Transport, regulation, protection, gas exchange, and communication

Volume of blood in an adult

5-6 L

pH of blood

7.35-7.45

Difference between plasma, buffy coat, hematocrit

Plasma is the liquid portion of blood and is 90% water, buffy coat is the thin white layer between plasma and blood cells composed of WBC and platelets and hematocrit is the % of total blood volume occupied by RBC

Life span of leucocytes

6 hours

Life span of erythrocytes

120 days

Hemoglobin

A protein in red blood cells that carries oxygen

Protein that carries oxygen

Can bind 4 molecules

Which blood cells do not have a nucleus?

Erythrocytes

Most plentiful protein in blood

Albumin

Function of lymphocytes

Immunity

Function of neutrophils

First to arrive at site of infection

Function of eosinophils

Kill parasites

Function of thrombocytes

Blood clotting

Function of monocytes

Fight chronic infection

What do monocytes develop into?

Macrophages

What is anemia?

Decrease of RBC

What is polycythemia?

Excessive amount of RBC

What is the number of leukocytes in 1 uL of blood?

5,000

What is the number of erythrocytes in 1 uL of blood?

5 million

What is the number of platelets in 1 uL of blood?

150,000

Define hemostasis

The process of stopping bleeding

Define fibrin

Protein that helps with clotting

Define hemophilia

Genetic disorder when blood does not clot properly

Thickest wall in heart

Left ventricle is thicker because left pumps blood through the whole body

Pathway of blood in heart

Vena cava—right atrium—tricuspid valve—right ventricle—pulmonary valve—pulmonary arteries—pulmonary veins—left atrium—bicuspid valve—left ventricle—aortic valve—aorta

Valves of the heart

Tricuspid valve, bicuspid valve, pulmonary valve, and aortic valve

Blood vessel that carries deoxygenated blood from the heart to the lungs

Pulmonary arteries

What is a myocardial infarction?

Heart attack; blockage of blood flow to parts of the heart

Cause of LUB heart sound

Closing of atrioventricular valves

Cause of DUB heart sound

Closing of semilunar valves

What are the nodes of the heart?

Sinoatrial node and Atrioventricular node

What are P, QRS, T waves?

P wave is atrial depolarization, QRS is ventricular depolarization, and T is ventricular repolarization

Smallest diameter blood vessels

Capillaries

Where does diffusion take place?

Capillaries

What cells is the endothelium made of?

Simple squamous

The highest blood pressure is found in what vessels?

Arteries

Where is the Cardiovascular center?

The medulla oblongata

Where are the baroreceptors located?

Carotid sinus and in the aortic arch

What is the pulse rate?

Heartbeats per minute (75)

Where do all systemic arteries branch off?

From the aorta

Difference between systemic and pulmonary circulation

The systemic arteries go to the entire body and the pulmonary goes to the lungs

Main vein that drains blood from the heart

Coronary sinus

Slowest blood flow is found in what vessels?

Capillaries

The highest blood pressure is found in what arteries?

In the aorta