1. Human physiology 6.2 Transport System 6.4 Gas Exchange 6.1 Digestion
6.3 Defense against infectious diseases
HL 11.1 Defense against infectious diseases

2. 6.2 Transport System
Average resting heart rate: 60 – 100 beats/min

5. 2.6 Your Blood Erythrocytes : carries oxygen via hemoglobin
Leucocytes: part of immune system
Plasma: carries all other components of blood
Platelets: clotting of blood following damage
Materials transported by blood: Oxygen, nutrients, hormones, antibodies, heat, carbon dioxide, urea

6. Lung and heart Deoxygenated blood from body  heart  lungs
Oxygenated blood from lungs  heart  body

7. 6.2.1 The Heart

8. 6.2.3 Action of the heart Collection of blood: Pumping of blood:
deoxygenated blood enters the right atrium from the inferior and superior vena cava
oxygenated blood enters the left atrium from the pulmonary vein
Pumping of blood:
contraction of the atria (right and left) pumps the blood into the ventricles (right and left)
contraction of ventricles (right and left) pumps the blood into the pulmonary artery (right) and aorta (left)

9. 6.2.3 Action of the heart opening and closing of valves:
as a function of pressure differences, one-way valves prevent backflow of blood
atrioventricular valves prevent backflow from ventricles into atria
semilunar valves prevent backflow of blood from pulmonary artery into right ventricle and from aorta into left ventricle
Relaxation: The "lub" is the sound of the tricuspid and mitral valves closing.
Contraction: The "DUB" is the sound of the aortic and pulmonary valves closing.
How a heart attack occurs:

10. Vinnie Jone’s hard and fast CPR
Learn CPR in three steps:

11. 6.2 Transport system Submit Cells Quiz
Announcement: Learning Log (6.1, 6.2, 6.4), Lab
TED: Growing organs

14. 6.2.4 Beating of the heart is not a conscious process
Myogenic muscle contraction
Certain cells of vertebrate cardiac muscle (myocyte) are self excitable, meaning they contract without signal from the nervous system
Pace-maker myocyte: sino-atrial node (SAN)
located on the right atrium
impulses spread throughout both atria  atria contract
impulse spread to ventricles only at the atrio-ventricular node (AVN) with a delay of about 0.1 seconds  ventricles contract

15. Electrocardigram (ECG or EKG)
Impulses that travel through cardiac muscle produces electrical currents

16. 6.2.4 Speeding up/down heart rate
Exercise. More CO2 present in blood when exercising. Detected by receptors in medulla oblongata
Nerve stimulation:
sympathetic nerves from brain release epinephrine, increasing heart rate
parasympathetic nerves from brain via vagus nerve decrease heart rate
Hormone stimulation:
Adrenalin increases heart rate during fight-or-flight response

17. 2.5 Arteries & Veins Artery Vein
Thick walls of smooth muscle with elastic fiber
Small lumen
Valves prevent backflow of blood
Thin walls of smooth muscle with thin elastic fiber
Large lumen
Valves maintain one-way flow of blood
Carry blood away from heart under very high pressure and high speed
Return blood to heart with less pressure under low pressure and low speed

18. 2.5 Capillaries Function Structure
Diffusion of dissolved materials between blood & tissue
Low pressure and speed
Structure
No muscular wall
One cell thick
No valves

19. Blood pressure (arterial pressure)
Systolic pressure
Pressure created on arteries when heart beats (contraction of ventricle)
Normal range: 108 – 140 mm Hg
Diastolic pressure
Pressure in arteries when heart rests
Normal range: 60 – 90 mm Hg
Hypertension = blood pressure greater than 140/90 mm Hg