Biology Circulatory System

Circulatory System Components

Blood and Interstitial fluid

Interstitial fluid

Where nutrients are stored

Clear blood in invertebrates

Has hemolymph but does not have hemoglobin which makes the red colour

Funtions of the Circulatory System

1. Transport gases, nutrients, and waste material

2. Regulate internal body temperature and transport hormones

   1. Protects against blood loss and toxic substance introduced into the body

How the body regulates temperature

The vein pops out to dump heat energy out of the body.

Arteries

Carry oxygen rich blood away from the heart with some exceptions

Veins

Carry oxygen poor blood towards the heart with some exceptions

Capillaries

Functional unit of the circulatory system and transports nutrients, etc.

Artery Characteristic

They are thick and highly elastic walls. Arteries can withstand higher pressure

Blood travelling through the arteries

When the heart pumps, the artery rapidly expands due to the high pressure. It then snaps back to relaxation (pulse)

Vein Characteristics

They have thin and non-elastic walls and cannot contract

Blood travelling through the veins

Contraction of surrounding skeletal muscles that squeeze the blood in the veins.

Prevention of backwards blood flow

Have one way valves that act like doors.

Circumference of the Artery

Small circumference so it blasts blood and increase pressure because it arteries needs to travel fast

Circumference of Veins

Larger circumference because it does not need high pressure. Even if it does, the thin walls would not be able to handle the high pressure and tear.

Size of capillaries

Capillaries are one cell thick, called the Endothelial cell, that lines all blood vessels.

Speed of the Capillaries

They are the slowest in order to provide time for diffusion to happen across the cells.

Role of the Capillaries

Play a key role in the absorption, transportation, gases, waste, etc

Vasodialation

Increasing blood flow near skin to help release heat

Vasoconstriction

Decreases blood flow near the skin to conserve heat

Order of Heart Beat

Ventricle then Atriumis the sequence in which the heart contracts, typically starting with the atria and followed by the ventricles.

Atrium

Fill with blood returning to the heart

Ventricles

Fill with blood from atria to pump it away from the heart

Septum

Thick muscular wall that separates the left and right side of the heart

Atrioventricular Valves

Valves between the atrium and ventricle and it prevents backward bloodflow

Tricuspid valve

Right side and has 3 flaps

Bicuspid valve

Life side and has two flaps

Semilunar valves

Valves that control blood flow out of the ventricles and prevents backwards blood flow

Pulmonary Valves

Separates right ventricle from the pulmonary arteryand controls blood flow to the lungs. A

Aortic Valves

Between left ventricle and aortacontrols blood flow to the body.

Pulmonary Pathways

Transportation and gas exchange of O2 and CO2. Heart and lungs

Systemic pathway

Deliver oxygenated blood to tissues and remove waste. Heart to body.

Cortorary Pathway

Provide blood to heart tissues via right and left. Heart to heart muscles

Sinoatrial Nodes

Atria contracts and stimulates muscle cells to contract/relax rhythmically with an electrical signal.

Atrioventricular Nodes

Signal reaches the AV nodes and reaches the bundle of his

Purkinje Fibre

Causes the ventricles to contract effectively, facilitating blood ejection to the lungs and body.

Electrodiagram

Measure the change in voltage produced from the SA node

Heart Murmurs

Valves do not close all the way which makes the heart less efficient

Side effects of Heart Murmurs

Heart enlargements and faster beating

Blood pressure

Amount that the blood is pushing against the vessels

Systolic pressure

Maximum blood pressure during contractionDia

Diastolic Pressure

Lowest pressure before the ventricles contract again

Systole

Ventricles contract, which shuts the AV valves and opens semilunar valves to pump blood out of the heart

Diastole

Atria contractions and ventricles are relaxed, which causes the AV valves to open and shut the semilunar valves. This allows blood to fill the heart

Sphygmomanometer

Blood pressure measured at an artery.

Normal blood pressure

120/80H

Hypertension

High blood pressure which leads to strokes, heart attacks

Plasma

Red and white blood cells, platelets, water, enzymes, Amino acids, monosaccharides

Solid portion of the blood

Formed portion

Red blood cells

Also called Erythrocytes, is specialized for oxygen transport, and the bioconcave shape allows for more surface area as well as it to slide against other red blood cells

White Blood Cells

Also called Leucytes, it is the body’s response to infections

Platelets

Fragment of cells that form larger ones when bone marrow cracks. Plays a role in blood clotting