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HIV Infection: Viral life cycle

By: HWC, Views: 7094

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...

Natural Selection, Species Isolation and Real World Example

By: HWC, Views: 7175

`Natural selection' is the process in which organisms with adaptive traits survive and breed in greater number than organisms without such traits. Eventually, almost all of the individuals in the population will have the same adaptive trait. This was the concept presented by Charles Darwin in ...

Mechanics of Sound Animation

By: Administrator, Views: 10994

Process of Hearing Sound waves are directed to the eardrum, causing it to vibrate. These vibrations move the three small bones of the middle ear (malleus, incus, and stapes). Movement of stapes at oval window sets up pressure waves in the perilymph and endolymph. Process of Hearing The wav...

Role of the urinary system - acidosis and alkalosis

By: HWC, Views: 7967

• Tubular cells of the proximal convoluted tubule and collecting tubules can alter filtrate pH and therefore blood pH. • These cells can affect blood pH with two coupled mechanisms: • Reabsorption of bicarbonate ions. • Secretion of hydrogen ions. • The reabsorption of bicarbonate...

Endocytosis -Types and Phagocytosis

By: HWC, Views: 7775

Endocytosis is the process by which a substance is brought inside a cell without having to pass through the cell membrane. It is the opposite of endocytosis, the process by which substances exit the cell without having to pass through the cell membrane. Exocytosis – membrane-enclosed secret...

Regulation of GFR: three methods, autoregulation & autoregulation via myogenic mechanism

By: HWC, Views: 8179

• GFR can be regulated by adjusting: • Blood flow in and out of the glomerular capillaries. • Surface area of glomerular capillaries. • There are three main ways to make these adjustments: • Renal autoregulation. • Nervous regulation. • Hormonal regulation. • Ren...

Neuron structure and function - sensory neurons, association neurons & motor neurons

By: HWC, Views: 7673

• The primary function of the nervous system is to provide rapid communication within the body to maintain homeostasis. • This function underlies behaviors, thinking and control of organ functions. • The basic functions of the nervous system are provided by: • Sensory neurons • ...

Component of feedback systems & Communication and regulation of body systems

By: HWC, Views: 7867

• Primary responsibility for communication and regulation in the body is shared by the nervous and endocrine systems. • The two systems work alone or together in specialized physiological processes called feedback systems to maintain homeostasis. • Feedback systems - or loops - are ...

Evolutionary tree of life Animation

By: HWC, Views: 1404

An evolutionary tree of life that reflects mainstream thinking about the connections among major lineages (bya = billions of years ago, mya = millions of years ago). By about 3.8 billion years ago, chemical and molecular evolution had produced the first living cells. The first major divergenc...