Respiratory system

Functions

1. Moves oxygen from the outside environment into the body.

2. Removes carbon dioxide and water from the body

Why we need oxygen?

• The chemical reactions that produces energy inside the cells require oxygen.

Oxygen and Glucose are transported to the cells by the Circulatory system to produce energy

What is respiration?

• The process in which oxygen and glucose undergo a complex series of chemical reactions to release the energy.

• It produces carbon dioxide and water.

WHY WE NEED O2

What is Breathing?

• Is the process in which air flows into and out of the lungs

How do you breathe?

• The brain is in control

• Internal stimuli indicates how much O2 your body needs.

The process of breathing

• Muscle of breathing: diaphragm

• A large dome shaped muscle at the base of your lungs.

• When you – inhale or breath in the

diaphragm moves downward

– Exhale or breath out the diaphragm relax

How does the air travel and get into your body?

• The air travels from the outside environment to the lungs:

• Nose or Mouth

• Pharynx

• Trachea

• Bronchi

• Bronchioles

• Alveoli

• Blood Stream

Pharynx• The air moves from

the nose into the throat

• The food from the mouth moves to the throat because is part of the digestive system

Nose

• Two openings or nostrils, separated by a thin wall.

• The lining of the nose is coated with cilia and mucus.

• Trap particles and warm and moisten the air. Why?

trachea

• The wall of the trachea is made of cartilage rings.

• Why?• Trachea wall is lined

with cilia and mucus• Epiglottis prevents the

food to come inside the lungs

Bronchial tube

Large tubular structures within the lungs. These carry air into the lungs from the trachea. They branch into smaller tubes called bronchioles

Bronchiole

• The first airway branches that no longer contain cartilage. They lead to the alveoli.

Alveolus

• Tiny sacs of lung tissue whose structure specializes in exchanging gases (CO2 and O2)between the air and the blood

• The alveolus are surrounded by capillaries.

O and CO2 exchange• The blood coming from

the heart to the lungs is carrying a lot of Carbon dioxide and little Oxygen.

• Inside the alveoli the hemoglobin in your red blood cells attaches the Oxygen and at the same time is getting rid of the CO2

Larynx

• Also called the voice box

• An organ in mammals involved in protection of the trachea and sound production

Vocal cords• Folds of connective tissue that produce

your voice

• Are stretched across the opening of the larynx. Vibrate to produce sound.

Lungs

• Inside the lungs, each bronchus divides into smaller and smaller tubes

Diaphragm• it contracts, it pushes

downward and spreads out, increasing the vertical dimension of the chest cavity and driving up abdominal pressure

• dome-shaped sheet of muscle that inserts into the lower ribs.

Pleura

• A membrane which folds back upon itself to form a two-layered, membrane structure that surrounds the lungs.

Breathing and Homeostasis

• Homeostasis– keeping the internal environment of the

body balanced

– need to balance O2 in and CO2 out

– need to balance energy (ATP) production

• Exercise– breathe faster

• need more ATP

• bring in more O2 & remove more CO2

• Disease– poor lung or heart function = breathe faster

• need to work harder to bring in O2 & remove CO2

O2

ATP

CO2

Respiratory system conditions

• Asthma

• interactive system

• Tutorial

• label the parts

• Lungs

• Respiratory rap

• Respiratory system song music with the students to sing along

Optimizing gas exchange• Why high surface area?

– maximizing rate of gas exchange

– CO2 & O2 move across cell membrane by diffusion

• rate of diffusion proportional to surface area

• Why moist membranes? – moisture maintains cell membrane structure– gases diffuse only dissolved in water

High surface area?High surface area!Where have we heard that before?

Gas exchange in many forms…

one-celled amphibians echinoderms

insects fish mammals

endotherm vs. ectothermsize

cilia

water vs. land ••

Evolution of gas exchange structures

external systems with lots of surface area exposed to aquatic environment

Aquatic organisms

moist internal respiratory tissues with lots of surface area

Terrestrial

Gas Exchange in Water: Gills

Counter current exchange system

• Water carrying gas flows in one direction, blood flows in opposite direction

just keepswimming….

Why does it workcounter current?Adaptation!