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Primary Active Transport - electrochemical gradient and ion transport / water movement

By: HWC, Views: 6753

Energy derived from ATP changes the shape of a transporter protein which pumps a substance across a plasma membrane against its concentration gradient An electrochemical gradient is a gradient of electrochemical potential, usually for an ion that can move across a membrane. The gradient consis...

Forming urine ( influencing factors), Forming dilute urine & Forming concentrated urine

By: HWC, Views: 7093

• The amount of urine produced by the nephron depends on : • Body fluid volume. • Body fluid composition. • Dilute urine is formed when the body is normally hydrated. • The medullary osmotic gradient determines the osmolarity of the filtrate. • Filtrate osmolarity increase...

Non-polar compounds - insolubility

By: HWC, Views: 6678

• A non-polar molecule has uniform distribution of electrons. • Non-polar compounds like fatty acids in lipids have a high proportion of carbon and hydrogen. • Lipids possess no charge or partial charge. • Lipids are not attracted to water molecules. • Lipids are not soluble in...

How to make cDNA Animation

By: HWC, Views: 1229

This animation shows how an mRNA transcript can be used to make a cDNA strand.

Glycolysis - Introduction to ATP and the burning of sugar

By: HWC, Views: 6728

Do you use sugar with your coffee or tea? Or do you occasionally drink a sport or soft drink? As millions of people do each day, they obtain energy from the sugar added or contained in these drinks. How can we understand this concept of energy within a sugar molecule? Let's take a tablespoon ...

Antidiuretic hormone (vasoconstriction, water reabsorption & sweat inhibition)

By: HWC, Views: 6578

• Dehydration, blood loss, and low amounts of water in the blood can cause blood volume and pressure to decrease. • Neurosecretoxy cells in the posterior pituitary release antidiuretic hormone(ADH). • ADH binds to smooth muscle cells in blood vessel walls, stimulating them to vasoconstr...

Type of Transport - Active and Passive Processes

By: HWC, Views: 6861

Active transport moves materials from lower to a higher concentration, while passive transport moves materials from higher to lower concentration. Active transport requires energy to proceed, while passive transport does not require the input of extra energy to occur. Transport processes that ...

Properties of water -structure of water and polarity (Ionized and polar compounds)

By: HWC, Views: 6814

■ Water transports most of the molecules in the body. ■ The structure of a water molecule allows it to dissolve other molecules. ■ Shared electrons spend more time near the oxygen atom. ■ Oxygen end has a partial negative charge. ■ Hydrogen ends have a partial positive charge....

Atrial natriuretic peptide (vasodilation) & Aldosterone

By: HWC, Views: 6326

• Certain situations will cause the body's stress level to rise. • increased blood pressure will stretch the atria of the heart, stimulating the secretion of atria natriuretic peptide (MP). • ANP causes muscle cells in blood vessels to relax. • Blood pressure is lowered as a result ...