Transcript Oxygen-poor blood Oxygen

KEY CONCEPT
The respiratory and circulatory systems
bring oxygen and nutrients to the cells.
The respiratory and circulatory
systems work together to maintain
homeostasis.
• The circulatory system transports
blood and other materials.
– brings supplies to cells
– carries away wastes
– separates oxygen-poor and oxygenrich blood
Oxygen-rich blood
Oxygen-poor blood
• The respiratory system is where gas exchange occurs.
– picks up oxygen from inhaled air
– expels carbon dioxide and water
When you stand up after
lying down, why do your
heart rate and breathing
rate increase?
sinus
nose
mouth
epiglottis
trachea
lungs
The respiratory system moves gases
into and out of the blood.
• The lungs contain the bronchi, bronchioles, and alveoli.
• Millions of alveoli give the lungs a huge surface area.
• The alveoli absorb oxygen from the air you inhale.
alveoli
bronchiole
• Breathing involves the diaphragm and muscles of the rib
cage.
• Air flows from areas of high pressure to low pressure.
Air inhaled.
Air exhaled.
Muscles and
rib cage relax.
Muscles contract and
rib cage expands.
Diaphragm flattens
and moves downward.
Diaphragm relaxes
and rises.
The circulatory system moves blood to
all parts of the body.
• The system includes the heart,
arteries, veins, and capillaries.
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veins
heart pumps blood throughout body
arteries move blood away from heart
veins move blood back to heart
capillaries get blood to and from cells
arteries
• There are three major functions of the circulatory
system.
– transporting blood, gases, nutrients
– collecting waste materials
– maintaining body temperature
30.2 KEY CONCEPT
The respiratory system exchanges
oxygen and carbon dioxide.
Your cells perform cellular
respiration.
They need:
They give off:
Gas exchange occurs in the alveoli of
the lungs.
• Oxygen and carbon dioxide are carried by the blood to
and from the alveoli.
– oxygen diffuses from alveoli into capillary
– oxygen binds to hemoglobin in red blood cells
– carbon dioxide diffuses from capillary into alveoli
GAS EXCHANGES
ALVEOLI
capillary
alveolus
Co2 diffuses
into alveolus.
co2
o2
capillaries
O2 diffuses
into blood.
Gas exchange occurs in the alveoli of
the lungs.
• Breathing is regulated by the brain stem.
• This means you don’t have to think about it, Why is that
important?
midbrain
pons
medulla
oblongata
spinal chord
Respiratory diseases interfere with gas
exchange.
• Lung diseases reduce airflow and oxygen absorption.
– Emphysema destroys alveoli.
– Asthma constricts airways.
– Cystic fibrosis produces sticky mucus.
• Smoking is the leading cause of lung diseases.
KEY CONCEPT
The heart is a muscular pump that moves
the blood through two pathways.
The tissues and structures of the heart
make it an efficient pump.
• Cardiac muscle tissue works continuously without
tiring.
NORMAL HUMAN HEART
• The heart has four chambers: two atria, two ventricles.
• Valves in each chamber prevent backflow of blood.
• Muscles squeeze the chambers in a powerful pumping
action.
pulmonary valve
aortic valve
left atrium
right atrium
mitral valve
left ventricle
tricuspid
right ventricle
septum
• The heartbeat consists of two contractions.
– SA node, or pacemaker, stimulates atria to contract
– AV node stimulates ventricles to contract
SA node
VA node
• Blood flows through the heart in a specific pathway.
– oxygen-poor blood enters right atrium, then right
ventricle
– right ventricle pumps blood to lungs
– oxygen-rich blood from lungs enters left atrium, then left
ventricle
– left ventricle pumps blood to body
• Blood flows through the heart in a specific pathway.
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3
2
4
The heart pumps blood through two
main pathways.
• Pulmonary circulation occurs between the heart and the
lungs.
– oxygen-poor blood enters lungs
– excess carbon dioxide and water
expelled
– blood picks up oxygen
– oxygen-rich blood returns to heart
• Systemic circulation occurs
between the heart and the
rest of the body.
– oxygen-rich blood goes to
organs, extremities
– oxygen-poor blood returns
to heart
• The two pathways help
maintain a stable body
temperature.
KEY CONCEPT
Blood is a complex tissue that
transports materials.
Blood is composed mainly of cells,
cell fragments, and plasma.
• Whole blood is made up of different materials.
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plasma
red blood cells
white blood cells
platelets
plasma
red blood cells,
white blood cells,
and platelets
• Plasma is a key factor in maintaining homeostasis.
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molecules diffuse into and out of plasma
contains proteins that stabilize blood volume
contains clotting factors
contains immune proteins
Platelets and different types of blood
cells have different functions.
• The bone marrow manufactures most of the blood
components.
red blood cell
platelet
white blood cell
• Red blood cells make up 40-45 % of all blood cells.
– transport oxygen to cells and carry away carbon dioxide
– have no nuclei and contain hemoglobin
• White blood cells fight pathogens and destroy foreign
matter.
red blood cell
platelet
white blood cell
• Protein markers define blood types and Rh factors.
– ABO blood group the most common
– Rh factor can be negative or positive
– blood types must be compatible for transfusions
• Platelets help form clots that control bleeding.
platelets
fibrin
white
blood cell
red blood cell