Transcript Chapter 6- Transport

Transport
• Absorption and circulation of materials
Aim: How do materials enter and exit the
cell?
• Transport:
– Absorption and circulation of materials.
– Nutrients enter cells through diffusion
– Structure of the Cell Membrane:
– “Phospholipid Bi-layer”
– Made of proteins and lipids
Fluid Mosaic Model:
• Cell Membrane:
– Semi/selectively permeable
– Small molecules diffuse through membrane
– Regulates movement of materials into and out
of the cell based on size
Fluid Mosaic Model
Methods of Transport
• Passive Transport a.k.a Diffusion:
– No energy needed
– Movement from High to Low concentration until
equilibrium
Diffusion
– Movement of materials from highlow
concentration.
– Continues until equilibrium is reached
Diffusion of liquids
Small Molecules that diffuse through cell
membranes
•
Oxygen
•
Carbon dioxide
•
Water
•
Nutrients (simple
sugars, amino acids)
Osmosis
• Diffusion of H2O
• High low concentration
Active Transport (Needs ATP)
•
•
•
•
Energy is needed to move materials
Low high concentration
Against concentration gradient
No equilibrium reached
Active Transport
• Phagocytosis
– Cell engulfs undissolved molecules
• Pinocytosis
– Cell membrane pinches in and absorbs
dissolved molecules.
Phagocytosis:
Ameba engulfing food
Transport of Water in Cells
1. Place a cell in salt water
- water moves out of the cell – cell shrinks
- less water outside the cell – water moves
out
Salt Shrinks!
2. Place cell in distilled (pure) water
-water moves into the cell
`
-cell swells (could burst)
-less water in the cell
- water moves in
What would occur if a solution of salt H2O or
distilled (pure) water was added to a cell?
• Adding a salt solution:
– Since the concentration of H2O is higher inside the
cell, the water flows outward to the area of low
concentration. The water rushes out, the cell shrinks.
• Adding distilled (pure) water
– Since the concentration of H2O is higher outside of
the cell, the water flows inward to the area of low
concentration. The water rushes in, the cell could
eventually burst.
What happens to cells when placed in
different solutions?
Animal Cells shrivel like slugs in a
salt solution because water leaves
the cell!
Plant Cells also change when placed in
solutions!
Transport in Lower Organisms
-ex. Ameba, paramecium
1. Diffusion
2. Osmosis
3. Cyclosis
4. Endoplasmic Reticulum
Transport in Plants
vascular tissue: (veins)
-xylem – transports water
upwards
- phloem – transports food in
both directions
• Roots:
– Located under the ground. Provide support, anchorage,
and absorb water.
• Root hairs:
– Increase surface area for water absorption.
• Capillary Action:
–
–
–
–
–
Pulls H2O up in the xylem tubes.
This is because of adhesion and cohesion.
Adhesion- attraction between different molecules.
Cohesion- Attraction between like molecules.
H2O holds on to another H2O molecule.
• Adhesion
Cohesion
Chapter 12- Human Transport
•
•
•
•
Blood
Liquid tissue
Transport medium
Contains:
– Plasma
– Red Blood cells (RBC)
– White Blood cells (WBC)
– Platelets
Plasma
• Liquid portion of the blood, mostly water.
• Contains nutrients, wastes, proteins
– Proteins enzymes, hormones, and
antibodies.
Red Blood Cells (RBC- Erythrocytes)
•
•
•
•
•
Most numerous blood cell
Lack a nucleus when mature
Disc-shaped
Carries oxygen (O2) & carbon dioxide(CO2)
Contains hemoglobin-pigment that allows RBC
to carry O2 & CO2.
• Live for 120 days-broken down in the liver and
spleen.
• Produced in the bone marrow.
Red Blood Cells
White Blood Cells (WBC- Leukocytes)
•
•
•
•
•
Least numerous blood cell
Contains a nucleus
Large, round cell
Protects against infection
Phagocytes
– Engulf and destroy bacteria (phagocytosis)
• Lymphocytes
– Produce antibodies which attack foreign materials
called antigens.
White Blood Cells
Platelets
• 2nd most numerous blood cell
• Small
• Clot the blood-contain fibrin (protein)
The Human Circulatory System
• closed system
• single heart
• network of blood vessels
Blood Vessels
•
•
•
•
•
Arteries
Carry blood away from the heart
Thick wall
Elastic
Smallest arteries: arterioles
Veins
•
•
•
•
•
Carry blood to the heart
Thin wall
Not elastic
Valves – Prevent back-flow of blood
Smallest veins: venules
Capillary
• Connects small arteries and small veins
• One cell thick- thinnest vessel
• Where diffusion occurs: nutrients, wastes,
O2.
The Heart:
•
•
•
•
•
•
•
•
4 chambered muscular organ.
Divided into two halves by the septum.
Each half has 2 chambers
atrium “ upstairs”
 connected by a valve
ventricle “downstairs”
Atrium receives blood
Ventricles pump blood left ventricle is the thickest
because it pumps blood to the whole body!
• Heart is surrounded by the pericardium
Human Heart
Human Heart
Chambers Of The Heart
R
L
Right Atrium
Left Atrium
Right Ventricle
Left Ventricle
Flow of Blood Through The Heart
• 1. Superior & Inferior vena cava) –
deoxygenated blood
•
•
2. Right Atrium(tricuspid valve) Right ventricle
3. Right ventricle pumps deoxygenated blood to lungs
•
•
4. Pulmonary Artery – Blood travels to lungs (Only
Artery with deoxygenated blood)
5. Pulmonary Vein- Blood travels from lungs (Only
Vein with oxygenated blood)
6. Left Atrium
7. Left Ventricle- Thickest most muscular
chamber-pumps oxygenated blood through
the aorta to body!
8. Aorta – Largest Artery
Recipient
Donor
(person who needs blood)
(person who gives blood)
A
A,O
B
B,O
AB (universal recipient)
A,B,AB,O
O
O (universal donor)
Blood Typing
• Antigen- causes antibody reaction
• Antigens are proteins on surface of cells
(including blood cells types)
• Antibodies in plasma (anti-A or anti-B).
Blood Type
Antigens
Antibodies
A
A
Anti-B
B
B
Anti-A
AB
A,B
None
O
None
Anti-A, Anti-B
Statistics
Blood Pressure
• Pressure exerted on the walls of the
arteries during pumping.
• Systole- Ventricles contract
• Diastole- ventricles relax
• AVG. 120/80
Malfunctions of the Transport System
Cardiovascular Disease:
- diseases involving the heart
Heart Attack
1. Coronary Thrombosis
- blockage of an artery
2. Angina Pectoris
- narrowing of an artery
Angina Pectoris
Coronary Thrombosis
Blood Conditions
1. Anemia
- too few red blood cells
- lack of iron in blood
- difficulty transporting oxygen
2. Leukemia
- disease of bone marrow
- too many abnormal white blood
cells - cancer
Immunity
• Resistance to a specific disease.
• Pathogen- Bacteria, Virus
• Antigen- structure on surface of pathogen.
• Antibodies (specific proteins)- released
by the body to lock on and destroy the
antigens.
• Antigens and Antibodies are specific.
2 types of immunity
1. Active Immunity:
– Long-term
• Ways of obtaining:
– Produce antibodies in response to having
a disease/ sickness
– Getting a vaccine
Vaccination
• Vaccine
Weakened or dead form of virus/ pathogen.
• To make a vaccine– Obtain pathogen
– Weaken or kill pathogen (virus or bacteria)
– Inject into organism
– Organism makes antibodies
– antibodies make organism immune against
pathogen
2. Passive Immunity
– Short-term immunity
•
Ways of obtaining:
– Mother  baby during breast-feeding
– Antibodies from an outside source: gamma
globulins.
Allergies:
• Extreme sensitivity to antigens
• Antigens: pollen, dust, animal hair, etc.
• Body produces antibodies against the antigen.
– Antigenantibody body produces histamines
– Histamines causes allergic response(tearing, rash,
sneezing).
• To stop this reaction, you take anti-histamines
Antibodies are specific to antigens