HESI Anatomy & Physiology

Heart chambers pathway

Right atrium → Right ventricle → Lungs → Left atrium → Left ventricle → Body

Largest artery

Aorta

Largest vein

Inferior vena cava

Pulmonary arteries

Carry deoxygenated blood to the lungs.

Pulmonary veins

Carry oxygenated blood to the heart.

Left ventricle

Thickest heart chamber; pumps blood to the body.

SA node

Natural pacemaker of the heart.

Normal adult resting heart rate

60–100 bpm.

Normal blood pH

7.35–7.45

Red blood cells

Transport oxygen using hemoglobin.

White blood cells

Fight infection.

Platelets

Blood clotting.

Plasma

Liquid portion of blood.

Hemoglobin

Protein that carries oxygen.

Arteries

Carry blood away from the heart.

Veins

Carry blood toward the heart.

Capillaries

Site of gas and nutrient exchange.

Universal blood donor

O negative.

Universal blood recipient

AB positive.

Primary muscle of breathing

Diaphragm.

Gas exchange occurs in

Alveoli.

Trachea

Windpipe leading to the bronchi.

Epiglottis

Prevents food from entering the airway.

Bronchi

Carry air into each lung.

Bronchioles

Smaller branches leading to alveoli.

Pleura

Membrane surrounding the lungs.

Oxygen enters blood by

Diffusion.

Carbon dioxide leaves blood by

Diffusion.

Largest organ

Skin.

Largest internal organ

Liver.

Layers of skin

Epidermis → Dermis → Hypodermis.

Melanin

Pigment that gives skin color.

Sebaceous glands

Produce oil (sebum).

Sweat glands

Help regulate body temperature.

Largest bone

Femur.

Smallest bone

Stapes.

Longest bone

Femur.

Patella

Kneecap.

Scapula

Shoulder blade.

Clavicle

Collarbone.

Tibia

Weight-bearing shin bone.

Fibula

Smaller lower leg bone.

Humerus

Upper arm bone.

Radius

Thumb-side forearm bone.

Ulna

Pinky-side forearm bone.

Vertebral column sections

Cervical, Thoracic, Lumbar, Sacrum, Coccyx.

Ball-and-socket joints

Shoulder and hip.

Hinge joints

Elbow and knee.

Pivot joint

Atlas and axis (neck).

Skeletal muscle

Voluntary movement.

Smooth muscle

Found in organs; involuntary.

Cardiac muscle

Heart muscle; involuntary.

Largest muscle

Gluteus maximus.

Strongest muscle (force)

Masseter.

Biceps

Flexes the elbow.

Triceps

Extends the elbow.

Functional unit of kidney

Nephron.

Kidneys

Filter blood and produce urine.

Ureters

Carry urine to the bladder.

Bladder

Stores urine.

Urethra

Carries urine out of the body.

ADH

Increases water reabsorption.

Aldosterone

Increases sodium and water reabsorption.

Stomach function

Begins protein digestion.

Hydrochloric acid

Activates pepsin and kills bacteria.

Pepsin

Digests proteins.

Small intestine

Main site of digestion and absorption.

Duodenum

First part of the small intestine.

Jejunum

Absorbs most nutrients.

Ileum

Absorbs vitamin B12 and bile salts.

Large intestine

Absorbs water and forms feces.

Appendix

Contains lymphoid tissue.

Liver

Produces bile and detoxifies blood.

Gallbladder

Stores bile.

Pancreas

Produces digestive enzymes and insulin.

Bile

Breaks down fats.

Pituitary gland

Master endocrine gland.

Hypothalamus

Controls the pituitary and homeostasis.

Thyroid gland

Regulates metabolism.

Parathyroid glands

Increase blood calcium.

Adrenal glands

Produce cortisol, aldosterone, and epinephrine.

Pancreatic beta cells

Produce insulin.

Pancreatic alpha cells

Produce glucagon.

Insulin

Lowers blood glucose.

Glucagon

Raises blood glucose.

Neuron

Functional unit of the nervous system.

Dendrites

Receive signals.

Axon

Sends signals away from the cell body.

Myelin

Speeds nerve impulse conduction.

Brainstem

Controls vital functions.

Cerebrum

Thinking, memory, voluntary movement.

Cerebellum

Balance and coordination.

Medulla oblongata

Controls breathing and heart rate.

Sympathetic nervous system

Fight or flight.

Parasympathetic nervous system

Rest and digest.

Growth hormone

Stimulates body growth.

Negative feedback

Maintains homeostasis by reversing a change.

Positive feedback

Blood clotting and childbirth.

Mitosis

Produces two identical body cells.

Meiosis

Produces four genetically unique sex cells.