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Membrane Protein and Facilitated Transport (Passive Vs Active)

By: HWC, Views: 7360

Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins span the membrane, with hydrophobic amino acids interacting with the lipid bilayer and hy...

Oxygen transport - methods and oxyhemoglobin

By: HWC, Views: 7562

• The blood is the medium used for gas transport throughout the body. • Oxygen is only available in the lungs. Because the partial pressure of oxygen is higher in the alveoli than in the blood, oxygen diffuses into the blood and is transported to systemic cells. • At the tissues the par...

Heart sounds

By: HWC, Views: 7621

During a normal, healthy heartbeat, or what we call a cardiac cycle, the top two chambers of the heart, called the atria, contract simultaneously. Then, as they relax, the bottom two chambers, called the ventricles, contract. This explains what happens during a cardiac cycle, but what it doesn't ...

Glycolysis - Introduction to ATP and the burning of sugar

By: HWC, Views: 7859

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 ...

New DNA Strand Replication

By: HWC, Views: 7138

First step: strands are separated • Helicase unwinds the DNA double helix at the replication fork • SSBs coat the single strands to prevent reannealing • Polymerase attaches nucleotide at 3' end • Synthesis is in 5' to 3' direction DNA Polymerase: • Only extends nucleic ac...

Isovolumetric VC, Ventricular ejection, Isovolumetric & Passive ventricular filling

By: HWC, Views: 7696

• Isovolumetric means that blood volume does not change. • Ventricular blood volume and cell length remain constant. • With valves closed and contraction continuing, ventricular pressure continues to rise. • Ventricular pressure rises above arterial pressure. • Increased ventr...

Glomerubular filtrate rate -pressures that affect GFR and net filtration pressure

By: HWC, Views: 8189

• The glomerular filtration rate is the amount of filtrate formed per minute within the renal corpuscle. • Once the filtrate is formed it moves down the tubule. • The production and movement of filtrate depends on three pressures: I. Glomerular blood hydrostatic pressure (GBHP) is pre...

Second Messengers in the Inositol-lipid Signaling Pathway

By: HWC, Views: 7009

Extracellular signals produce specific responses in target cells through the action of intracellular second messengers. Here, we focus on three second messengers, IP3, DAG, and Ca2+, all involved in the inositol-lipid signaling pathway. A hormone-receptor signal on the cell surface leads to the a...

Origin of organelles Animation

By: HWC, Views: 1385

Possible origins of the nucleus and other organelles. Some prokaryotic cells have infoldings of their plasma membrane. These infoldings may have served as channels from the cytoplasm to the cell surface. These membranous folds may have evolved into the endoplasmic reticulum and the nuclear e...