Bio12 - Circulation Vocab

Anterior (Superior) Vena Cava

Anterior (Superior) Vena Cava

• Location: Upper right side of heart, near the sternum

• What: A large vein

• Function: Returns deoxygenated blood from the upper body to the right atrium of the heart

Antibody

• Location: Found throughout the immune system, particularly in bloodstream and lymph system

• What: A protective protein produced by immune cells

• Function: Identifies and neutralizes foreign invaders, like antigens

Antigen

• Location: Found on the surface of pathogens (bacteria and viruses) and within the body

• What: A substance (often a protein) that triggers an immune response

• Function: Prompts the production of antibodies to attack the foreign substance

Aorta

• Location: Extends from the left ventricle of the heart, traveling down the chest and abdomen

• What: The largest artery in the body

• Function: Distributes oxygenated blood from the heart to the rest of the body; systemic circulation

Arterial Duct

• Location: Connects the pulmonary artery to the aorta in fetal circulation

• What: A fetal blood vessel

• Function: Allows blood to bypass the lungs in the fetus, redirecting it from the right side of the heart to the body; fills in with cells after birth

Atrioventricular (AV) Valve

• Location: Between the atria and ventricles in the heart

• What: A type of heart valve

• Function: Prevents backflow of blood from the ventricles into the atria; separates atria from ventricles on each side of the heart

Autonomic Nervous System

• Location: Throughout the body, controlling various organs

• What: network responsible for unconscious actions (e.g. heartbeat, breathing, etc.)

• Function: Regulates involuntary functions like heart rate and digestion

Atrioventricular (AV) Node

• Location: Located between the atria and ventricles in the heart

• What: A cluster of cells within the heart’s electrical system

• Function: Sends electrical impulses to cause the ventricles to contract

Blood Pressure

• Location: Measured in arteries

• What: The force of blood against artery walls

• Function: Indicates the strength and health of the circulatory system (measured as systolic over diastolic)

Blood Velocity

• Location: Refers to the speed of blood flow within vessels

• What: The rate at which blood flows through the circulatory system

• Function: Influences the efficiency of nutrient and oxygen transport

Chordae Tendineae

• Location: Found in heart muscles, attached to valves

• What: Tendon-like cords

• Function: Anchors heart valves to prevent inversion during contraction; holds AV valves in place while heart pumps blood

Coronary Arteries and Veins

• Location: Heart surface

• What: Blood vessels for the heart muscle

• Function: Supplies oxygenated blood to the heart and removes deoxygenated blood

Diastolic pressure

• Location: Arteries

• What: Lower part of blood pressure reading

• Function: Measures pressure in arteries between heartbeats; the minimum pressure recorded just prior to the next contraction of ventricles

Fetal Circulation

• Location: In the fetus

• What: Circulatory pattern in a fetus

• Function: Bypasses the lungs, using the placenta for oxygenation

Hypertension

• What: Condition

• Function: High blood pressure, often due to narrowed arteries

Hypotension

• What: Condition

• Function: Low blood pressure, may cause dizziness and fainting

Left Atrium

• Location: Upper left chamber of the heart

• What: Heart chamber

• Function: Receives oxygenated blood from the pulmonary veins and sends it to the left ventricle

Left Ventricle

• Location: Lower left chamber of the heart

• What: Heart chamber

• Function: Pumps oxygenated blood to the body through the aorta

Lymph Capillaries

• Location: Throughout the body, particularly near tissues

• What: Small vessels of the lymphatic system (aka lacteals)

• Function: Collect excess fluid from tissues and absorb fats (fatty acids and glycerol) from the digestive tract

Lymph Nodes

• Location: Throughout the lymphatic system (neck, armpits, groin, etc.)

• What: Small, bean-shaped structures

• Function: Filter lymphatic fluid and help the body fight infections by trapping pathogens through lymphocytes (white blood cells)

Lymphatic System

• Location: Throughout the body

• What: Network of tissues and organs

• Function: Maintains fluid balance, absorbs fats, and supports immune function

Lymphatic Veins

• Location: Throughout the lymphatic system

• What: Vessels of the lymphatic system

• Function: Transport lymph fluid back to the bloodstream

Oval Opening

• Location: Between right and left atria in the fetal heart

• What: Hole in the fetal heart

• Function: Allows blood to flow from right atrium to left atrium in fetal circulation, bypassing the lungs

Plasma

• Location: Blood

• What: The liquid component of blood

• Function: Carries nutrients, hormones, and proteins to cells; removes waste products; carries all parts of blood through the circulatory system

Posterior (Inferior) Vena Cava

• Location: Lower part of the body to the right atrium of the heart.

• What: Large vein.

• Function: Carries deoxygenated blood from the lower body to the right atrium

Pulmonary Arteries

• Location: Between the heart and lungs

• What: Blood vessels

• Function: Carry deoxygenated blood from the right ventricle to the lungs; blood gets oxygen from lungs and gets rid of carbon dioxide

Pulmonary Circulation

• Location: Between the heart and lungs

• What: Part of the circulatory system, transportation system

• Function: Transports blood to the lungs for oxygenation and returns it to the heart

Pulmonary Trunk

• Location: Exits the right ventricle of the heart.

• What: Large artery, divides into the 2 pulmonary arteries that lead to each lung

• Function: Carries deoxygenated blood from the right ventricle at the pulmonary valve to the lungs

Pulmonary Veins

• Location: Lungs to the left atrium

• What: Veins

• Function: Carry oxygenated blood from the lungs to left atrium of the heart

Purkinje Fibers

• Location: Inner walls of the heart’s ventricles

• What: Specialized muscle fibers

• Function: Conduct impulses to cause ventricles to contract

Right Atrium

• Location: Upper right chamber of the heart.

• What: Heart chamber (receiving)

• Function: Receives deoxygenated blood from the body and pumps it to the right ventricle

Right Ventricle

• Location: Lower right chamber of the heart

• What: Heart chamber (pumping)

• Function: Pumps deoxygenated blood to the lungs through the pulmonary arteries

Sinoatrial (SA) Node

• Location: Upper wall of the right atrium

• What: Cluster of cells, aka the pacemaker

• Function: Initiates heartbeats by sending electrical impulses, causing the atria to contract; receives message from the brain

Semi-Lunar Valve

• Location: Between ventricles and arteries (pulmonary artery to right ventricle, aorta to left ventricle)

• What: Type of heart valve

• Function: Prevents blood from flowing back into the ventricles; allows blood to be pumped forward into arteries

Septum

• Location: Center of the heart.

• What: Wall of tissue.

• Function: Separates the right and left sides of the heart; keeps oxygenated blood from mixing with deoxygenated blood

  • also prevents blood from flowing back into heart chambers after pumping out

Systemic Circulation

• Location: Entire body

• What: Part of the circulatory system

• Function: Carries oxygenated blood from the heart to the body and returns deoxygenated blood to the heart; provides oxygen and nutrients to parts of body (organs)

Systolic Pressure

• Location: Arteries

• What: Higher part of blood pressure reading

• Function: Measures pressure in arteries when the heart contracts; the maximum pressure during the contraction of the ventricles

Umbilical Artery

• Location: In the umbilical cord (fetal circulation)

• What: Blood vessel

• Function: Carries deoxygenated blood from the fetus to the placenta; low oxygen, low nutrients, high waste

Valve

• Location: Various locations in the heart and veins

• What: Structure in blood vessels and heart

• Function: Ensures blood flows in one direction; prevents backflow in and out of ventricles

Veins

• Location: Throughout the body

• What: Blood vessels

• Function: Carry deoxygenated blood back to the heart

Venous Duct

• Location: Fetal circulation, connects umbilical vein to the vena cava

• What: Duct in fetal blood circulation

• Function: Allows oxygenated blood to bypass the liver in the fetus