Cardiovascular

The body’s transport system: heart, blood, blood vessels: arteries, capillaries and veins.


Blood carries:

Oxygen -> lungs -> tissue

CO2-> tissues -> lungs

Nutrients -> whole body

Waste -> cells -> kidneys

Horomones

Heat


Arteries:

  • carry blood away from the heart

  • Oxygen rich blood


Arteroiles

  • very small branches of arteries


Capillaries

  • tiny blood vessels that connect to indiviual cells

  • Allow oxygen, nutrients and waste to move between blood and tissue


Veins:

  • Carry blood back to the heart

  • Oxygen poor blood



Absolutely — here are the simplified study notes with the most important definitions and facts.

❤ Cardiovascular System

What is it?

Cardiovascular system: The body’s transport system. It includes:

  • ❤ Heart

  • 🩸 Blood

  • 🛣 Blood vessels: arteries, capillaries, and veins

What does blood transport?

Blood carries:

  • Oxygen → lungs → tissues

  • CO₂ → tissues → lungs

  • Nutrients → throughout the body

  • Waste → cells → kidneys

  • Hormones

  • Heat


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🩸 Blood Vessels

Arteries

  • Carry blood away from the heart.

  • Usually carry oxygen-rich blood.

Arterioles

  • Very small branches of arteries.

Capillaries

  • Tiny blood vessels that connect to individual cells.

  • Allow oxygen, nutrients, and waste to move between blood and tissues.

Veins

  • Carry blood back to the heart.

  • Usually carry oxygen-poor blood.

Easy memory:
A = Arteries = Away from heart
V = Veins = back to the heart


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❤ The Heart

The heart acts like a pump that moves blood around the body.

Blood flow

Left side of heart
→ receives oxygen-rich blood from lungs
→ pumps it into the aorta
→ blood travels to the rest of the body

Right side of heart
→ receives oxygen-poor blood from the body
→ pumps it to the lungs
→ blood picks up oxygen again

Cardiac Cycle

The cardiac cycle is the heart’s pattern of contraction and relaxation.

Systole

  • Heart contracts

  • Blood is pumped out

  • Blood pressure increases

Diastole

  • Heart relaxes

  • Blood enters the heart

  • Blood pressure decreases

Blood Pressure

Blood pressure is written as:

Systolic / Diastolic

Example: 120/80

  • Top number = systolic pressure

  • Bottom number = diastolic pressure


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🩺 What Affects Blood Pressure?

Blood pressure is affected by:

  1. Volume of blood flow

  2. Peripheral resistance → resistance to blood flow in small arteries

  3. Condition of artery walls → damaged or clogged arteries can increase resistance


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❤ Cardiovascular System Disorders

Atherosclerosis

Atherosclerosis: Plaque, often containing cholesterol, builds up inside arteries.

This can:

  • Reduce blood flow

  • Prevent nutrients from reaching tissues

  • Damage tissues

  • Increase the chance of blood clots

Angina pectoris

Angina: Chest pain caused by the heart not getting enough oxygen or not removing waste/CO₂ properly.

Myocardial infarction

Myocardial infarction = heart attack

  • A blood clot blocks blood flow to the heart.

Arteriosclerosis

Arteriosclerosis: Hardening of the arteries.

  • Arteries become less flexible.

  • Can increase blood pressure.

Aneurysm

Aneurysm: A bulge in a weakened artery wall caused by pressure.

  • If it ruptures, it can cause serious internal bleeding.

Phlebitis

Phlebitis: Inflammation of a vein.

Can cause:

  • Pain

  • Water retention/swelling

  • Greater risk of blood clots

Hypertension

Hypertension: Chronically high blood pressure.

Can be caused by:

  • High cardiac output

  • Increased resistance to blood flow

Management can involve paying attention to:

  • Diet

  • Physical activity

  • Stress

  • Other lifestyle factors


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🩸 The Blood

The human body has about 5 litres of blood.

About 55% is plasma.

Plasma: The liquid part of blood.

The rest is mostly blood cells.

Blood cells are made in the bone marrow.

Types of Blood Cells

White blood cells

  • Help protect the body from infection.

  • Destroy foreign substances.

Lymphocytes

  • A type of white blood cell.

  • Produce antibodies to fight infections and disease.

Red blood cells

  • Contain hemoglobin.

  • Carry oxygen and CO₂.

Platelets

  • Help repair damaged blood vessels.

  • Help blood clot.


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🩸 Blood Disorders

White Blood Cell Disorders

Leukemia

Leukemia: A type of cancer involving the bone marrow that causes abnormal/excessive white blood cell production.

This can interfere with normal blood cells.

Leukopenia

Leukopenia: Too few white blood cells.

  • Makes a person more vulnerable to infections.


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🔴 Red Blood Cell Disorders

Anemia

Anemia: Too few red blood cells or too little hemoglobin.

Often related to iron deficiency, because iron is needed to make hemoglobin.

Possible symptoms:

  • Fatigue

  • Weakness

  • Dizziness

  • Shortness of breath

  • Cold hands and feet

Aplastic anemia

Aplastic anemia: The bone marrow has trouble making enough blood cells, resulting in reduced oxygen-carrying capacity.

Sickle cell anemia

Sickle cell anemia: A genetic disorder where red blood cells have an abnormal sickle/crescent shape.

These cells can break down more easily, which can cause anemia.


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🩸 Clotting Disorders

Hemophilia

Hemophilia: The body does not produce enough of certain substances needed for blood clotting.

This causes excessive or prolonged bleeding.

Thrombosis / Blood clots

A thrombus is a blood clot that forms inside a blood vessel.

Clots can become dangerous if they block blood flow, especially to important organs such as the heart or brain