topic 8: exchange and transport in animals

Surface Area to Volume Ratio

The relationship between the size of an organism and its outer surface area.

Exchange Surfaces

Specialized surfaces like alveoli or villi that allow substances to move in and out of the body.

Alveoli

Tiny air sacs in the lungs where gas exchange occurs.

Adaptations of Alveoli

Large surface area thin walls and a rich blood supply to maintain a concentration gradient.

Villi

Finger like projections in the small intestine that increase surface area for nutrient absorption.

Concentration Gradient

The difference in concentration between two areas that drives diffusion.

Ficks Law

The rate of diffusion is proportional to surface area times concentration gradient divided by thickness of membrane.

Diffusion

The passive movement of particles from an area of high concentration to an area of low concentration.

Thickness of Membrane

A factor that decreases the rate of diffusion as it increases.

Red Blood Cells

Cells that carry oxygen using a protein called hemoglobin.

White Blood Cells

Cells that form part of the immune system to fight pathogens.

Plasma

The liquid part of the blood that carries dissolved carbon dioxide urea and hormones.

Platelets

Small fragments of cells that help the blood to clot at a wound.

Arteries

Blood vessels that carry blood away from the heart at high pressure.

Veins

Blood vessels that carry blood towards the heart at low pressure and contain valves.

Capillaries

Tiny blood vessels with one cell thick walls to allow exchange of materials.

Valves

Structures in the heart and veins that prevent the backflow of blood.

Double Circulatory System

A system where blood passes through the heart twice for every one complete circuit of the body.

Right Atrium

The chamber of the heart that receives deoxygenated blood from the body.

Right Ventricle

The chamber that pumps deoxygenated blood to the lungs.

Left Atrium

The chamber that receives oxygenated blood from the lungs.

Left Ventricle

The chamber with the thickest muscular wall that pumps oxygenated blood to the whole body.

Vena Cava

The main vein bringing deoxygenated blood back to the heart.

Pulmonary Artery

The artery that carries deoxygenated blood to the lungs.

Pulmonary Vein

The vein that carries oxygenated blood from the lungs to the heart.

Aorta

The main artery that carries oxygenated blood from the heart to the body.

Respiration

A chemical reaction that occurs in all living cells to release energy from glucose.

Aerobic Respiration

Respiration that uses oxygen to break down glucose into carbon dioxide and water.

Aerobic Respiration Word Equation

Glucose plus oxygen produces carbon dioxide plus water.

Mitochondria

The organelle in cells where aerobic respiration takes place.

Anaerobic Respiration

Respiration that takes place without oxygen producing lactic acid in animals.

Lactic Acid

A waste product of anaerobic respiration that causes muscle fatigue and cramp.

Oxygen Debt

The amount of extra oxygen needed after exercise to break down accumulated lactic acid.

Cardiac Output

The total volume of blood pumped by a ventricle every minute.

Cardiac Output Formula

Heart rate multiplied by stroke volume.