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 highlow 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 SystemCardiovascular Disease:

- diseases involving the heartHeart Attack1. Coronary Thrombosis- blockage of an artery2. 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

• VaccineWeakened 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.– Antigenantibody body produces histamines– Histamines causes allergic response(tearing,

rash, sneezing).

• To stop this reaction, you take anti-histamines

Antibodies are specific to antigens