Chapter 5-7 human biology

Function of Cardiovascular System

Transport, Protection, Regulation (homeostasis)

Two Major Components of Cardiovascular System

Heart (pumps blood) & Blood vessels (pathway for blood flow)

Types of Blood Vessels

Arteries, Arterioles, Capillaries, Venules, Veins

Arteries Function

Carry blood away from heart; thick, elastic walls

Arterioles Function

Small branches of arteries; control blood flow into capillaries

Capillaries Function

One cell thick; site of gas & nutrient exchange

Venules Function

Collect blood from capillaries and join to form veins

Veins Function

Carry blood toward the heart; have valves to prevent backflow

Muscle in Arteries and Veins

Smooth muscle (involuntary)

Muscle in Heart

Cardiac muscle (involuntary)

Lymphatic Vessel Function

Collect excess fluid & return it to bloodstream

Fluid in Lymphatic System

Lymph (not blood)

Main Blood Pathway

Heart → Arteries → Arterioles → Capillaries → Venules → Veins → Heart

Two Blood Circuits

Pulmonary (lungs) & Systemic (body tissues)

Pulse

Surge of blood through arteries as heart beats

Myocardium

Thick middle layer of heart; contracts

Systole

Heart contraction phase

Diastole

Heart relaxation phase (chambers fill with blood)

Valve Function

Prevents blood backflow

Cardiac Cycle

One complete heartbeat (contraction + relaxation)

Hypertension

High blood pressure; blood moves at higher rate

Hypotension

Low blood pressure

Intercalated Discs

Connect heart cells; allow electrical signal passage

Aneurysm

Ballooning of a blood vessel

Atherosclerosis

Plaque buildup in arteries

Embolus

Traveling blood clot

Angina Pectoris

Chest pain from reduced heart blood flow

Four Chambers of Heart

Right atrium, Right ventricle, Left atrium, Left ventricle

Right vs. Left Side of Heart

Left = oxygenated, thicker wall; Right = deoxygenated, thinner wall

Heart Valves (Names)

Tricuspid, Bicuspid (mitral), Pulmonary semilunar, Aortic semilunar

Thicker Myocardium Side

Left ventricle; pumps blood to entire body

Major Vessels Near Heart

Aorta, Pulmonary arteries/veins, Superior & Inferior vena cava

Largest Artery

Aorta

Varicose Veins Cause

Weak valves in veins

Coronary Arteries & Veins

Arteries deliver O₂ to heart muscle; veins remove CO₂

Resting Heart Rate

60–100 bpm

Normal Blood Pressure

120/80 mmHg

Natural Pacemaker

SA Node (Sinoatrial node)

ECG Waves

P wave (atria contract), QRS (ventricles contract), T wave (ventricles recover)

Extrinsic Heart Controls

Nervous system (sympathetic, parasympathetic), temperature, emotions

Device to Measure BP

Sphygmomanometer (with stethoscope)

Silent Killer

Hypertension (few symptoms)

Heart Attack vs. Stroke

Heart attack = blood to heart blocked; Stroke = blood to brain blocked

Heart Attack Symptoms

Chest pain, nausea, sweating, dizziness

Stroke Symptoms

Face drooping, weakness, vision trouble, headache

Functions of Blood

Transport, Defense, Regulation

Type of Tissue

Fluid connective tissue

Two Blood Components

Plasma (liquid), Formed elements (cells & platelets)

Three Main Plasma Proteins

Albumins, Globulins, Fibrinogen

Red Blood Cells (RBCs)

Carry oxygen; no nucleus; biconcave shape

White Blood Cells (WBCs)

Fight infection; have nucleus

Platelets

Cell fragments for blood clotting

RBC Life Cycle

Made in red bone marrow; live ~120 days; destroyed in liver/spleen

Erythropoietin

Hormone from kidneys; increases RBC production

Anemia

Too few RBCs or hemoglobin → fatigue & weakness

Neutrophil

Granular WBC; phagocytizes pathogens & debris

Eosinophil

Granular; fights parasitic infections

Basophil

Granular; releases histamine, promotes inflammation

Lymphocyte

Agranular; immunity & antibody production

Monocyte

Agranular; becomes macrophage; phagocytizes debris

Platelets = Thrombocytes

Not true cells; formed from megakaryocytes in bone marrow

Stages of Clot Formation

Injury → Platelet plug → Prothrombin activator → Fibrin clot

Antigen

Foreign molecule that triggers immune response

Antibody

Protein that binds specifically to an antigen

Agglutination

Clumping when incompatible blood types mix

Type A Blood

A antigens, Anti-B antibodies

Type B Blood

B antigens, Anti-A antibodies

Type AB Blood

A & B antigens, No antibodies (universal receiver)

Type O Blood

No antigens, Anti-A & Anti-B antibodies (universal donor)

Rh Positive (+)

Has Rh antigen; no Rh antibodies

Rh Negative (–)

No Rh antigen; develops antibodies if exposed

Hemolytic Disease of Newborn

Mom (Rh–) makes antibodies against Rh+ baby → treated with RhoGAM shot

Transfusion Reaction

Wrong blood type causes clumping & blockage

Blood Test Info

WBC count (infection), Platelet count (clotting), Blood type compatibility

Bone Marrow Biopsy Purpose

Check blood cell production and marrow health

Blood Cancer Name

Leukemia (originates in WBCs)

Three CO₂ Transport Forms

Dissolved, Carbaminohemoglobin, Bicarbonate ions

Lymphatic System Functions

Absorb excess fluid, absorb fats, produce lymphocytes, defend against pathogens

Primary Lymph Organs

Red bone marrow & thymus

Secondary Lymph Organs

Lymph nodes, spleen, tonsils

Thymus Function

Matures T cells; larger in children

Lymph Nodes Function

Filter lymph; contain B & T cells

Spleen Function

Filters blood; contains white and red pulp

Pathogen Definition

Disease-causing organism

Immunity Definition

Ability to resist disease or infection

Innate Immunity

Nonspecific defenses: barriers, inflammation, phagocytosis

Adaptive Immunity

Specific, has memory (B and T cells)

Humoral Immunity

B cells + antibodies fighting pathogens outside cells

Cell-Mediated Immunity

T cells attack infected or cancerous cells

Allergies

Hypersensitivity to harmless substances

Anaphylactic Shock

Severe allergic reaction; can be fatal

Inflammation Signs

Redness, heat, swelling, pain

Phagocytic WBCs

Neutrophils, macrophages, dendritic cells

Cytotoxic T Cells

Kill infected or cancer cells

Helper T Cells

Regulate immune response

Memory T Cells

Provide long-term immunity

IgG

Main antibody in blood; activates complement

IgM

Found in circulation; first responder; clumps cells

IgA

In saliva, milk; prevents pathogens attaching to tissues

IgD

On immature B cells; signals readiness