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Respiratory System

Human Respiratory System

� A system to deliver oxygen (O2) to body

cells & get rid of carbon dioxide (CO2) as a waste through cellular respiration.

� Two systems involved:

Respiratory &

Circulatory Systems.

Cellular Respiration

Glucose + O2 C02 + H20 + Energy

� Glucose in cells is broken down to release energy (ATP) when O2 is

present.

� ATP is cell’s energy for

cell work!

Label diagram…

About the About the About the About the Respiratory SystemRespiratory SystemRespiratory SystemRespiratory System

Nostrils

� Openings to the respiratory system at the

nose.

Nostrils

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Cilia & Mucus

� Cilia

- sweeps, warms, & traps particles to filter

away from the lungs.

� Mucus

- cells that moisten to trap particles

Nasal Passages (Cavity)

� Cilia lined passages that end (terminate)

at the pharynx; acts like a humidifier.

Nasal

Passage

Pharynx (throat)

� Space at the back

of the oral cavity

where the mouth

and nose meet.

Epiglottis

�Flap of tissue that covers the tracheal opening

to prevent food fromentering the lungs (choking).

Larynx

�Also, called the

voice box

(the site for

vocal cords).

Needed to

create sound.

Larynx

Larynx

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Trachea: (windpipe)

� A cartilage ringed structure that remains

open so air can travel to the lungs.

Trachea

Bronchi

� Right and Left major

divisions of the trachea;

lined with cilia.Left Bronchus

Right Bronchus

Smaller

Bronchioles

� Smaller subdivisions of the bronchi after

they have entered into the lobes of the lung; not made of cartilage.

Bronchioles

BronchiolesBronchioles

Lung

� Balloon-like structures in the chest that

bring oxygen into the body and expel (release) carbon dioxide from the body.

Alveoli (air sacs)� Small thin air sacs at the end of the

bronchioles surrounded with capillaries to allow for gaseous exchange.

Alveolar

Sac

Alveoli

Capillary

network

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Respiratory Surface

� A thin, moist surface to help for gas exchange by diffusion.

� Surface must be in contact with free oxygen.

Ex: Unicellular organisms (protists, amebas, paramecium)

- Cell membrane & environment

Ex: Multicellular organisms

- Specialized organs & transport system

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter1/animation__the_pleural_membranes.html

Diaphragm� A sheet of muscle that separates the

thoracic (chest) and abdominal cavities.

Chest Cavity

Abdominal Cavity

Breathing

� The movement of air into and out of the lungs.

� No muscles are connected to the lungs.

� Air pressure drives air into our lungs.

� Increased CO2 levels in body, triggers (tells) brain to bring air into lungs.

The Mechanics for

Breathing

� Boyle’s Law

� Diaphragm Movement

�The Control Center for Breathing

Boyle's Law:

The inverse (opposite) relationship between volume & pressure.

� Inhalation

- increase in volume (air rushing in)

- decrease in pressure.

� Exhalation

- decrease in volume (air leaving)

- increase in pressure.

Summary On

Diaphragm Breathing

Inhalation Exhalation

Air flows inLung expands(inflates)

Air flows outLung contracts(deflates)

Diaphragm contracts& moves downward (descends).

Diaphragm relaxes & moves upward (rises).

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2 Phases of Breathing

http://www.footprints-science.co.uk/breathing1.htm

Worksheet Exercise

http://www.footprints-science.co.uk/alveoli.htm

• In the ALVEOLI, O2

diffuses into capillary

when you inhale.

• In the CAPILLARY,

CO2 diffuses into the

alveoli to be exhaled.

The Control for Breathing

Medulla Oblongata

Diaphragm&

Chest Muscles

Lung Contractions& Air enters lungs

Exercise� Muscles need O2 because O2 is needed to

make ATP (energy source).

� Causes:

- fast heartbeat, faster/deeper breathing, & sweat

- higher concentration of CO2 & low O2 in muscle cells.

- increase blood flow so more O2 in blood.

Hemoglobin on the RBC

Carries

O2 & CO2

http://health.howstuffworks.com/sports-physiology8.htm

Medical Disorders

(Malfunctions)

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Cigarette Smoking� Paralyzes the cilia & can cause many

diseases.

� blood vessels.

� Major cause for heart disease.

Group Roles

� Leader: Keeps group on task

� Recorder: Keeps a written record of groups

work

� Reporter: Presents group’s work to class

� Noise monitor: Keeps groups voices

manageable

Bronchitis

� Bronchi and bronchial tubes become

irritated & swollen.

� Symptoms: cough, sore throat, yellow or

green mucus

�Cause: smoking, bacteria, viruses

�Treatment: Treat symptoms or antibiotics

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Asthma

� An allergic response

� Bronchioles narrow

� Symptoms: wheezing, coughing, & difficulty breathing.

�Cause: pollutants in air, emotions, unknown

�Treatment: medications (inhalers)

Tightened muscles

Excess mucus

Inflamed lining of bronchioles

Alveoli filled with trapped air

Asthma

Pneumonia

� Alveoli (air sac) fills up with fluid.

� Symptoms: high fever, cough, increase

mucus, chills

� Causes: bacteria, virus, fungus

�Treatment: Antibiotics

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Fluid filled air spaces

PneumoniaEmphysema

� Lungs lose elasticity (can’t stretch).

� Alveoli wall is damaged and breaksdown.

� Less surface area for gas exchange.

� Irreversible (can’t reverse)

� Symptoms: mild cough, weight loss, tired

� Cause: Years of smoking destroys alveoli

� Treatment: Oxygen therapy (O2 tank)

Overinflated & broken alveolar sacs

Broken alveolar capillaries

Bronchioles

EmphysemaLung Cancer

� Uncontrolled growth of abnormal lung cells

(no function), can spread.

� Symptoms: new cough, cough with blood,

shortness of breath

� Causes: smoking , pollutants

� Treatments: surgery, chemotherapy, radiation treatment.