Excretion - How metabolic wastes are removed from the body
- Wastes include heat, water, carbon dioxide, nitrogenous compounds, and salts
-Made from breakdown of proteins
Excretion in Protists
One word
Diffusion
CO2
CO2
CO2 CO2
CO2
CO2
CO2
Human Excretory System
- Excretory organs include liver, kidneys, lungs and skin
Liver - Detoxifies harmful materials
- Removes bacteria, drugs, and hormones from blood and turns them
into less harmful substances
- Breaks down amino acids to form urea
- Urea travels to kidneys where it is removed as urine
Cirrhosis - Disease of liver
- Liver is overloaded with harmful substances (alcohol)
- Leads to death
- Very common in alcoholics
13,000 deaths in US per year
The Lungs
- Excrete carbon dioxide and waters
Skin - Removes heat through sweat and capillaries dilating
Urinary System
Kidney’s - Bean shaped organs in lower back
- Remove metabolic wastes from blood
- Concentrates substances in body fluids
25% of blood pumped each minute goes to
kidney’s to be filtered.
Each day about 180 L of filtrate
comes out of your blood most is
reabsorbed. Only about 1 to 1.5 leaves
as urine.
Most of water
removed from blood is
reabsorbed in this
little loop
Ureter - Where urine leaves kidney’s and travels to the bladder
Bladder
Urethra
- Stores urine
- Tube that urine leaves through
Dialysis - If kidney’s do not function properly patients blood
can be cleaned with a machine
- Must be done 2 – 3 times a week for rest of life
Kidney Stone’s - Some dissolved materials crystallize out in kidneys
- Can be surgically removed, or sound waves or lasers can
break them apart
- More common in men
Gout - Uric acid builds up in joints causing arthritis
like symptoms
Respiration - The process by which an organism exchanges oxygen
and carbon dioxide
Not the same as cellular respiration
Respiratory Surface - Where gas exchange occurs
(1) Thin walled so that… diffusion can take place easily
(2) Must be moist so gases can dissolve and go into solution
(3) It must be in contact with an oxygen source
(4) In multicellular organisms must be in contact with transport
system
Gas exchange in simple organisms takes place by diffusion
O2
O2
O2
O2
CO2 CO2
O2
O2
CO2
CO2
O2
CO2 CO2
CO2
O2
O2
CO2
O2
CO2 CO2
O2
CO2
O2
O2
O2
O2
O2
Where is the CO2 that is inside each of the organisms above
coming from?
What will the O2 be used for and which organelle will it
eventually end up in?
O2
Human Respiratory System
Nasal Cavity - Channels that allow air into body
- Lined with ciliated cells that produce mucus
- Mucus (aka snot) - sticky stuff, traps dust, bacteria etc
In the nasal cavity air is:
1.) Filtered - Nose hairs trap particles, cilia and mucus
trap and remove particles
2.) Moistened - Mucus added to air lets air become moist
3.) Warmed
- Capillaries in nasal passage warm air
before it gets to delicate tissue of lungs
Pharynx - Back of mouth
Larynx (voice box) – made of mostly cartilage
Time for gross!
- Has two membranes stretched over cartilage
- The epiglottis keeps food from going here
Trachea ( windpipe) - 12cm long 2.5 in diameter tube leading to lungs
- Horseshoe shaped cartilage keeps it open at all times
- Lined with cilia that will move trapped
particles up to phyranx
Smoking 1 cigarette stops cilia
from working for 20 minutes.
Smokers cough is caused by excess
mucus building up in airways
Bronchi Branches to the two lungs
- contains cilia and is ringed with cartilage
- Continue to divide into smaller tubes called bronchioles
- Bronchioles do not have cartilage
Alveoli (air sacs) - Found at ends of each bronchiole
- Are only one cell thick and are the actually
respiratory surface of the lungs
- Are surrounded by capillaries
- CO2 diffuses from capillaries into alveoli
- O2 diffuses from alveoli into capillaries
-smoking interferes with uptake of oxygen in air sacs
- About 1/3 of particles inhaled from cigarettes remain in alveoli
- Phagocytic macrophages slowly remove these particles
Gas Exchange in Humans
Breathing
- Involuntary process controlled by medulla of brain
Diaphragm - Muscle on floor of chest
- Pushes air out and can create a vacuum to let air in
- Breathing rate increases with increase in CO2 levels in blood
Diseases of the Respiratory System
Asthma
- Severe allergic reaction in which bronchioles
contract making breathing diffucult
- Rarely fatal but very uncomfortable
- Inhalers used to cause bronchioles to relax
Bronchitis - Bronchial tubes become inflamed
- Passageways to alveoli become swollen and clogged
- Severe cough and diffuculty breathing
- More common in smokers than nonsmokers
Emphysema - Lungs lose elasticity
- Walls of alveoli breakdown causing pockets of air to develop
- People have shortness of breath
- Mostly found in smokers
- Chronic cough is early warning sign
- Can not be cured, oxygen can be given for minor relief
Pneumonia - Alveoli fill with fluid
- Can be caused by virus or bacteria
- Often follows cold or sore throat
- Person dies by drowning
Lung Cancer
- Tumors form in the lungs
- Symptoms include chronic cough, bloody mucus, pain in chest
- Much more common in smokers
Tuberculosis - Alveoli are attacked by bacteria causing lesions to develop
in lungs
- Blood absorbs bacteria from tissue , spreading them throughout body
- Used to be fatal but is now highly curable
Laryngitis
-mucus membrane of larynx becomes inflammed
- Vocal chords become inflamed causing horseness
- If continues for long time could be cancer
Cystic Fibrosis - Genetic disease in which persons lungs fill with mucus
- People with the disease have life expectancy of 30 years
- Life expectancy is increaseing dramatically
Describe a research plan for developing a new therapy for
people with Cystic Fibrosis.