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HIV Infection: Viral life cycle

By: HWC, Views: 6002

The series of steps that HIV follows to multiply in the body. The process begins when HIV encounters a CD4 cell. The seven steps in the HIV life cycle are: 1) binding; 2) fusion; 3) reverse transcription; 4) integration; 5) replication; 6) assembly; and 7) budding. Many viruses f...

Second Messengers in the Inositol-lipid Signaling Pathway

By: HWC, Views: 5863

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...

Types of synapses - electrical & chemical

By: HWC, Views: 6677

• Neurons communicate with one another or effector cells via synapses that allow information to be filtered and integrated. • The two types of synapses are: • electrical • chemical. • Electrical synapses, also known as gap junctions, contain many ion channels (connexons) conne...

Central Nervous System Animation

By: Administrator, Views: 9707

Consists of the brain and spinal cord. CNS receives impulses from throughout the body processes the information responds with an appropriate action Brain and spinal cord can be divided into: gray matter (unsheathed cell bodies and true dendrites) white matter (myelinated nerve fibers) ...

Neural regulation of mechanical digestion- CNS voluntary, ANS & ENS controlled involuntary movements

By: HWC, Views: 6558

• The gastrointestinal [GI] tract is basically a muscular tube that contains and processes food as it moves from the mouth to the anus. • Mechanical digestive functions consist of both voluntary and involuntary muscle contractions and relaxation including: • Chewing and swallowing food....

Factors that affect conduction rates (myelination, axon diameter & temperature)

By: HWC, Views: 6734

• Several factors determine the rate of conduction of action potentials: • Myelination • Axon diameter • Temperature • The step-by-step depolarization of an axon is called continuous conduction and occurs along unmyelinated axons. • Neurons in the PNS have many axons that ...

Labor and Childbirth - The Three Stages of Labor: Dilation, Expulsion & Placental مراحل الولادة

By: HWC, Views: 7119

Regulation of labor and birth - effects of estrogen and oxytocin on onset of labor • Just prior to birth, high placental corticotropin-releasing hormone levels stimulate the production of more estrogen. • High estrogen levels overcome the inhibitory effects of progesterone on uterine sm...

How proteins function? How do proteins work?

By: HWC, Views: 6258

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...

Metabolic Rate, Heat and Thermoregulation - response to heat and cold stresses

By: HWC, Views: 6845

• A neuron group in the anterior portion of the hypothalamus controls heat balance. • Neurons in the preoptic region of the hypothalamus integrate signals that come from thermoreceptors. • The temperature control center in the preoptic region propagates control signals to two other part...