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Second Messengers in the Inositol-lipid Signaling Pathway

By: HWC, Views: 5901

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...

Non-specific disease resistance mechanisms & Skin's defense barriers

By: HWC, Views: 6581

• Non-specific disease resistance acts quickly to fight a wide variety of invaders. • Mechanisms include: • Barriers • Antimicrobial substances • Cellular defenses • Inflammation • Fever Barriers - types • Physical and chemical bathers prevent invasion by micro...

Five phases of cardiac cycle & Atrial contraction

By: HWC, Views: 6651

1. Atrial contraction (atrial systole). 2. Isovolumetric (ventricular) contraction. 3. Ventricular ejection. 4. Isovolumetric (ventricular) relaxation. 5. Passive ventricular filling. Beginning of cardiac cycle • Prior to atrial contraction: • Atria and ventricles are relaxed....

How proteins function? How do proteins work?

By: HWC, Views: 6291

How proteins function is really about how proteins "do work" in cells. How do proteins work? Let's start thinking about protein function by looking at something important to you: your hair. Keratin is a structural protein that is composed of 2 intertwined or helical strands. Keratin is also f...

Mechanism of enzyme action

By: HWC, Views: 6573

â–  The substrate makes contact with the active site. â–  A change in the shape of the enzyme occurs resulting in the transformation of the substrate. â–  A substrate may undergo decomposition, have its atoms rearranged, or two substrates may be synthesized. â–  The products of the reaction...

Uterine (menstrual) cycle - phases

By: HWC, Views: 6693

• The uterus goes through a cyclical developmental pattern to be ready for implantation and support of an embryo. • The uterine, or menstrual, cycle is under the control of ovarian horrnones. • The uterine cycle also has three phases: • Menstrual phase • Proliferative phase â€...

Anaphylaxis Animation

By: Administrator, Views: 9422

Anaphylaxis is a serious, life-threatening allergic reaction. The most common anaphylactic reactions are to foods, insect stings, medications and latex. If you are allergic to a substance, your immune system overreacts to this allergen by releasing chemicals that cause allergy symptoms.

ATPase function - membrane transport, contractile proteins and synthesis

By: HWC, Views: 7055

• Energy from ATP is used to move ions across the cell membrane during active transport. • This membrane protein transports sodium out of the cell and potassium into the cell. As such, it is called a sodium-potassium pump. • Because this pump also acts as an enzyme to hydrolyze ATP it i...

Pasteur's Experiment

By: HWC, Views: 6031

Louis Pasteur designed a procedure to test whether sterile nutrient broth could spontaneously generate microbial life. To do this, he set up two experiments. In both, Pasteur added nutrient broth to flasks, bent the necks of the flasks into S shapes, and then boiled the broth to kill any existing...