9.1

Respiration and Motor System

Breathing: is the process that brings O2 into the lungs and expels CO2

It uses the diaphragm (which pushes up) and intercostals muscles.

It supplies the body with oxygen so that ATP can be formed by cellular respiration

Respiration: is the process by which oxygen is obtained from the environment and delivered to the cells.

There are two types: External respiration Internal respiration

External respiration: occurs in the lungs

Internal respiration: occurs within the body

Use your text (Chapter 9) to define and give the function of the following structures.

Some may not be in your text…..I will help you.

Tongue, pharynx, larynx, epiglottis, trachea, cilia, bronchi, bronchioles, alveoli, capillaries, pleural membrane, pleural space

Tongue- part of the oral cavity

Pharynx-throat; collect air from mouth and nose and passes it to the trachea

Larynx- voice box; contains the vocal cords

Epiglottis- small flap of tissue that guards the entrance to the trachea; closes when food is swallowed

Trachea-windpipe; passage leading from pharynx to lungs

Cilia-very small hair-like structures that moves mucous containing dust, debris etc up into the throat where it can be removed or swallowed

Bronchi- main branches of the trachea; tubes that lead into the lungs

Bronchiole-smallest subdivisions of the bronchi

Alveoli- small air sacs where gas exchange occurs

Capillaries-microscopic blood vessels that are imbedded in the walls of the alveoli; site of gas exchange

Pleural membrane - a thin membrane that surrounds the outer surface of the lungs

Pleural space -space between the membranes surrounding the lungs, and lines the inner wall of the chest

Diaphragm- a strong wall of muscle separating the chest cavity from the abdominal cavity

Ribs- bones that support and protect the chest cavity; move to a limited degree and help the lungs expand and contract

Activity: Label the lung diagram

Nasal cavity

Pharynx

Larynx

Trachea

Bronchi

Bronchioles

Aveoli

1. Air enters through the nasal cavity or mouth Air is:

-Warmed

-Moistened

-Cleaned Hairs filter and trap dust Mucous traps particles and keeps cells

lining the cavities moist

2. Air moves to the pharynx (throat)

3. The air is then carried to the larynx(voice box)

The larynx consists of two thin elastic sheets that vibrate when air is forced through them….. which produces sound

Inflammation due to an infection causes swelling and can cause Laryngitis

The voice is projected by the Adam’s apple (A thick band of cartilage)

4. The air then continues on down the Trachea

The trachea: is protected by the epiglottis It is covered with cilia which sweep

debris from the respiratory tract It also contains mucous which traps

debris

5.Then air travels through the left and right bronchi

6. Then to bronchioles; which are composed of smooth muscles……. they can decrease in diameter

7. The air then goes into tiny sacs called aveoli

Aveloi Is the site of gas exchange.. which is

by diffusion Each is covered in capillaries

(microscopic vessels)

8. Gas is then transported in the blood to the heart by the pulmonary vein

Pressure in your chest cavity varies because of the movement of your thoracic cavity

When your thoracic cavity: Expands….. pressure drops Compresses…. pressure rises

Gases move from an area high pressure to an area of low pressure

Inhaling and exhaling occur because of the differences between atmospheric pressure and pleural pressure

Inspiration (inhaling) occurs when the pressure inside the lungs is less than it is in the atmosphere

Expiration (exhaling) occurs when the pressure inside the lungs is greater than it is in the atmosphere

Diaphragm: is a dome shaped sheet of muscle that separates the thoracic cavity form the abdominal cavity

The intercostal muscles and diaphragm contract and relax to cause pressure changes in the chest

1. the diaphragm contracts and moves down

2. the intercostal muscles contract and move ribs up and out

3. The chest cavity becomes bigger and as a result pleural pressure is less than atmospheric pressure

4. air moves IN  

1. diaphragm relaxes and moves up

2. intercostal muscles relax and move ribs down and in

3. chest cavity is smaller as a result pleural pressure is higher than atmospheric pressure

4. air moves OUT

Your Assignment: Page 287 1-9

Daltons Law of partial pressure states: that each gas in a mixture exerts its own pressure independently of all other gases in the mixture.

The partial pressure of oxygen and carbon dioxide differs depending on location

Very high outside (atmosphere) High in alveoli Medium in blood Low in tissues Therefore O2 diffuses IN

Very high in tissues High in blood Medium in alveoli Low outside (atmosphere) Therefore CO2diffuses OUT 

1. diffuses into blood through capillaries in the aveoli

2. combines with hemoglobin on red blood cells to form oxyhemoglobin

3. diffuses into cells (used in cellular respiration)

4. Or it dissolves in plasma

Diffuses out of cells and into the blood

In the blood CO2 will do one the following: combine with hemoglobin on red blood

cells to form carbaminohemoglobin dissolve in plasma…forming carbonic

acid by combining with H2O

It then diffuses out of the blood through capillaries in the aveoli

Describes how both molecules travel in the blood stream

Both rely on the molecule hemoglobin

Is a molecule on the surface of RBCs

It consists of polypeptides that are composed of heme, and globin

Heme: is the iron-containing pigment… oxygen or carbon dioxide binds to this

Globin: is the protein component

What would be the effect of eating a diet that is low in iron?...... What would be the symptoms you feel and why would you feel this way?

In the lungs O2 attaches itself to a hemoglobin (on red blood cells) to form oxyhemoglobin

O2 travels as oxyhemoglobin to: the pulmonary vein the heart and is pumped through the arteries arterioles and the capillaries

At the capillaries H+ ions dislodge O2

O2 diffuses into the extra cellular space and then into the cells

Two methods:

1. It can combine with hemoglobin

2. dissolve in the plasma

1.Combining with Hemoglobin

(27%) CO2 combines with hemoglobin on the red blood cells to form carbaminohemoglobin

It is then transported to the lungs

2.Combining with H2O in the plasma

(64%) of CO2 combines with H2O to form carbonic acid

CO2 + H2O H2CO3(aq)

carbonic anhydrase… found in the RBC’s catalyzes this reaction

carbonic acids lowers the pH of the blood It is unstable and dissociates to form a

hydrogen ion and bicarbonate ion

  H2CO3 HCO3- + H+

Bicarbonate ions are transported to the lungs in the plasma

  The H+ ions dislodge oxygen from

hemoglobin

H+ ions then combines with hemoglobin forming reduced hemoglobin.. which returns to the lungs in venous blood

In the blood, the reduced hemoglobin acts as a buffer Buffer: is a substance that is able to neutralize

acids and bases

At the lungs, H+

dislodges from hemoglobin It combines with bicarbonate ions to

form water and carbon dioxide

HCO3- + H+ CO2 + H2O

CO2 diffuses from the capillaries in the aveoli into the lungs and is exhaled

controlled by the medulla oblongata

CO2 levels in Blood Stretching of lung tissue Emotional state Serious injury

Receptors: are used to detect changes in the environment (E.g. hot, cold, pain)

This information is sent to your central nervous system (brain & spinal cord)

Chemoreceptors: detect changes in chemicals in the blood

there are two types of chemoreceptors

CO2 receptors

O2 Receptors (used as a backup only)

these are the most sensitive receptors

they are the main regulators of breathing rate

are located in the medulla oblongata

CO2 dissolved in the blood forms carbonic acid

High levels of carbonic acid stimulate receptors in the medulla oblongata

The medulla oblongata sends a signal to the intercostal muscles and the diaphragm to increase breathing rate

once CO2 level return to normal, the chemoreceptors become inactive and breathing rate returns to normal

these receptors are only stimulated when O2 levels drop and CO2 levels remain constant

E.g. carbon monoxide present

are located in the carotid artery and aortic arteries

If O2 levels are low, receptors send a signal to the medulla oblongata to stimulate the intercostal muscles and the diaphragm to increase in breathing rate

On the top of a mountain which receptors would be activated? And why

At high altitudes- fewer O2 molecules are found breathing is

Asphyxiation- too much CO2 breathing is

  Hypoxia- not enough O2 no

warning….

it binds faster than O2 to hemoglobin and prevents O2 from binding….. No oxygen gets to the tissues = death

After running you are taking deep breaths

stretch receptors in pleura, bronchioles and alveoli are stimulated

nerve impulses are sent to the medulla oblongata (respiratory centre)

  breathing rate drops

fear and pain increase in breathing rate due to the increased need for O2

Being hit in the stomach drives abdominal organs upward

This exaggerates the dome shape of the diaphragm and reduces the volume of the chest cavity

A large quantity of air is expelled

Bronchitis: is the narrowing of the bronchi or bronchioles due to inflammation of the mucous lining

excess mucus is produced tissue swell …reduces the diameter

of the bronchi or bronchioles

very serious if it infects the bronchioles (there is no cartilage for support)

Inflammation

Imagine spending the rest of your life panting just to lift a fork………

Becoming short of breath to put your socks on………

Needing to rest after you lift up the remote………..some people do……

Inflammation of the alveoli causes air sacs to lose their elasticity, stretch and then rupture

It becomes difficult to exhale Air becomes trapped in the lungs With less alveoli there is decrease

oxygen levels Cause: smoking

This is preventable…….

Don’t let it happen …. !

Together Emphysema and Bronchitis = Chronic obstructive pulmonary disease (COPD)

Inflammation of the bronchioles as a result of particulates in the air or allergens

The bronchioles constrict and a greater effort is required to exhale

CO2 pressure builds in the lungs………

Cilia in your bronchioles sweep debris away from your lungs…..protecting them from bacteria and pollutants

The chemicals in tobacco smoke kill the cells that contain

cilia….more debris enters your lungs

The tar in tobacco smoke: coats the cilia disabling them

from keeping debris from your lungs

Carbon monoxide in smoke starve cells of oxygen….they can’t

make ATP

The Cyanide in cigarettes stops the electron transport

chain….. preventing ATP being made…without energy the cells die

Your lungs need to last for the rest of your life…..the average age of a person in Canada is 75 years

Why do this to yourself…..

Page 295-296 Read the Case Study Assignment Page296 #’s 1-6

Your Assignment: Page, 295 1-2 Your Assignment: Page, 297 1-10

1. Total Lung Capacity (TLC) total air held in lungs ~5800 mL

2. Tidal Volume (TV) air entering and leaving during

normal inhale and exhale ~ 500 mL

3. Inspiratory Reserve Volume (IRV) additional air that can be taken into

lungs ~ 3000 mL

4. Expiratory Reserve Volume (ERV) extra air that can be expelled from lungs ~ 1100 mL

5. Residual Volume (RV) air always left in your lungs

(otherwise there would be no pressure in them and they wouldn’t inflate!)

~ 1200 mL

6. Vital Capacity (VC) TV + IRV + ERV (total lung capacity

minus the residual volume) ~ 4600 mL

Total Lung capacity (TLC)

Vital Capacity (VC)

Expiratory Reserve (ERV)

Respiratory Reserve (RV)

InspiratoryReserve (IRV)

Tidal Volume (TV)

Handout: Label the Lung Volume diagram

9.4 Muscles

Resistance training increases the size of muscles

Bio 20

Notes

Bio

20

Not

es

Please ….no more notes Ms. Gillis!!!!

Biology

Muscles: are attached to the skeleton by tendons

convert chemical energy into kinetic

The work they do is done when they shorten; during contraction

A nerve signal triggers contraction

antagonistic muscles: are muscles that have the opposite action

E.g. When your bicep is flexed your tricep muscle is relaxed

The muscle that contracts to bend a joint is called a flexor

The muscle that must contract to straighten a joint is called an extensor

There are three types of muscle: Smooth Cardiac Skeletal

Smooth Muscle

Lines the digestive tract, uterus and arteries

It does not fatigue easily

It is long and tapered at each end

It is arranged in parallel lines forming sheets

Contraction occurs without conscious thought

Cardiac Muscle

It is unique to the heart which is part of the cardiovascular system

Contraction is involuntary

the cells are tubular, striated (have bands of dark and light)

The cells are branched creating a netlike structure

Skeletal Muscle

There is over 600 in your body

They are used for locomotion

Contraction is voluntary

They are attached to bone by tendons

They are tubular and striated,and have many nuclei

are made of bundles of muscles fibres

A layer of connective tissue wraps around each bundle and blood vessels and nerves innervate these

Each bundle consists many muscle fibres that are surrounded by connective tissue

Muscle fibres consist of myofibrils which are hundreds of thousands of cylindrical subunits

Each subunit is made of protein structures called myofilaments

Myofilaments are responsible for muscle contraction

Muscle

Muscle-fibre bundle

Muscle fibre

Myofibrils

Myofilaments

There are two types of microfilaments: Actin Myosin

It’s a theory that provides a model that helps explain how muscles contract

Muscles cause movement by shortening

The actin filament slide over the myosin filaments

Muscle

shortening

The head of myosin moves …. like flexing your wrist

The actin filament is chemically bonded to myosin and gets pulled along with it when it flexes

The actin filament then slides past the myosin myofilament in the direction of the flex

This continues, each time requiring ATP to provide energy

ATP is needed to reposition myosin head before each new flex

After contraction, the actin and myosin filament disengage and the muscle begins to relax

Energy demand in muscle tissue is met by aerobic respiration

Very little ATP can be stored in muscles tissue

Creatine phosphate: is a high energy compound found in

muscles it ensures that ATP supplies remain

high

Creatine phosphate supplies a phosphate to adenosine diphosphate (ADP) ……. replenishing ATP supplies

As long as oxygen is supplied and cellular respiration can meet the demands for ATP the muscle will contract

If energy demand is higher lactic acid fermentation results

Lactic acid causes pain and the muscle eventually fails to contract (this occurs during oxygen debt)

Rapid breathing occurs as a result of your body trying to restore the oxygen dept

A muscle contraction or twitch is caused by a nerve impulse

One impulse can stimulate several muscle cells

The strength of a contraction depends on the frequency of the stimulus

1. A nerve cell stimulates a muscle cell

2. There is a pause ..called the latent period….. (between the nerve impulse and the muscle contraction)

3. The muscle contracts/shortens…. actin slides over myosin

4. Actin and myosin disengage

5. The muscle begins to relax and then returns to its original size

How fast your muscle contracts depends on myosin

There are three forms of myosin: Type I Type IIa Type IIx

Your body contains all three types but you have more of one type

Type I: cause slow muscle twitches break down ATP slowly are found in greater abundance in long

distance runners

It is important to breakdown ATP slowly so that you have lots of energy

Type IIa and IIx: cause a faster twitch breaks down ATP faster… are less efficient rely on anaerobic respiration Found in greater abundance in sprinters

It is important to break down ATP fast…. and have that burst of energy

Muscles require nourishment and regular exercise

Motor system injuries are common in people who perform heavy lifting or who are involved in sports….

Examples of injuries are: Torn muscles/sprains Tendonitis: inflammation of tendons

due to over use or injury stretched tendons

Torn ligaments Joint dislocations: movement of the

joint out of its socket

The arthroscope is a needlelike tube, less than 2mm wide, that is equipped with a fibreoptic light

The needle is inserted into the knee

The lens provides a picture of the damage within

This image (within the knee) is projected onto a screen

The arthroscope is fitted with thin surgical tools that can snip away unhealthy tissue

Normally hospitalization is not required

What are some pros and cons to society for this type of technology?

Your Assignment: Page 304, 1-7 Your Assignment: Review Page 308, 1-21