04.30 BIO, HN U4P3 Transport in Humans & Plants (ALL)

Rate of Diffusion is increased by?

-Increasing surface area
-Decreasing diffusion distance
-Creating a greater concentration difference

Transport in Plants

-Require CO2 and H2O for photosynthesis which they acquire via roots and leaves
-Release O2 via stomata (diffusion) and H2O via leaves (transpiration)

System Level

-via the network of blood vessels that make up the circulatory system

Cellular Level

-between the body fluids like blood and interstitial fluids and the cells and tissues of the body

Circulatory System

-Transports materials in body via blood pumped by heart:
*Oxygen (O2)
*Carbon dioxide (CO2)
*Nutrients (glucose)
*Wastes

Respiratory System

-Supplies cells with oxygen
-Removes carbon dioxide
-Gas exchange occurs in alveoli
-O2 from alveolus (lungs) → capillaries (blood)
-CO2 from capillaries (blood)→ to alveolus (lungs)

Diffusion of oxygen and carbon dioxide in Alveoli

-Large number of alveoli in lungs
-Large, flat cells lining the alveoli increase surface area
-Cells lining the alveoli are one cell thick decreasing distance
-Breathing ensures a high concentration of oxygen in alveoli

Digestive System

-Villus is functional unit of small intestine
-Villi absorb nutrients via cellular transport
-Capillaries → monosaccharides / amino acids
-Lymph vessels → glycerol / fatty acids

Microvilli

-Microscopic cellular membrane protrusions
-Increase the surface area of cells
-Involved in a wide variety of functions, including absorption, secretion, cellular adhesion
-Found on epithelial linings, inner ear, taste buds, olfactory receptors

Urinary System

-nephron is functional unit
-Eliminates nitrogenous wastes
-Maintains acid - base balance
-Regulates water and electrolytes

Nervous System

-neuron is functional unit
-Fast-acting control system
-Responds to internal and external change
-Activates muscles and glands
-axon- away from cell body
-dendrite- toward cell body