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B cells and antibodies

By: HWC, Views: 9757

What Are Antibodies? Antibodies, also known as immunoglobulins, are Y-shaped proteins that are produced by the immune system to help stop intruders from harming the body. When an intruder enters the body, the immune system springs into action. These invaders, which are called antigens, can be vi...

The Hypothalamus: The Body's Thermostat (Human Thermostat)

By: HWC, Views: 8207

Normal body function requires a relatively constant body temperature, which is regulated by the body's thermostat, a region of the brain called the hypothalamus. The hypothalamus generates a temperature set point for the body and appears to be the major site for the integration of temperature inf...

hGH, Thyroid hormones & Aldosterone

By: HWC, Views: 9031

Glycogenolysis and lipolysis • Stressors stimulate production of a hypothalamic releasing hormone (GHRH). • The releasing hormone stimulates somatotroph cells of anterior pituitary to secrete human growth hormone. • Human growth hormone targets liver cells and fat cells. hGH (glycog...

Role of complement proteins

By: HWC, Views: 8770

• Non-specific and specific defense mechanisms work through the functions of complement proteins. • As soon as pathogens penetrate the physical barrier of the skin, other resistance mechanisms begin. • Cells, such as macrophages, phagocytize pathogens. • These cells increase exposu...

Interview with Person who has Panic Attacks

By: Administrator, Views: 12039

Panic attacks are sudden periods of intense fear that may include palpitations, sweating, shaking, shortness of breath, numbness, or a feeling that something bad is going to happen. The maximum degree of symptoms occurs within minutes. Typically they last for about 30 minutes but the duration can...

Green alga life cycle Animation

By: HWC, Views: 3494

Chlamydomonas zoospores are haploid flagellated cells. As long as conditions are favorable, these cells reproduce asexually. As many as sixteen cells may form by mitosis within a parent cell. Daughter cells escape when the cell wall ruptures. When conditions become less favorable, the...

Proteins Defined, Hierarchy & Composition of Cells

By: HWC, Views: 8431

Proteins are long chains of amino acids linked together by peptide bonds. Together with the other three biological macromolecules—carbohydrates, lipids, and nucleic acids—proteins are the building blocks of cells. Proteins are the most complex and abundant biological macromolecules in cel...

Fertilization Animation

By: Administrator, Views: 464

At conception, the gender and other biologic traits of the new individual are determined. The zygote is genetically complete and immediately begins to divide, forming a solid mass of cells called a morula. When the developing embryo (stage of development between weeks 2 and 8) reaches the ute...

A Human Karyotype Preparation Animation

By: HWC, Views: 6183

Blood is collected from the person being analyzed. The blood is added to a growth medium that also contains a chemical that stimulates mitosis. The cells are allowed to grow in this medium for two or three days at body temperature. Colchicine is added to arrest cell division at metaphase. T...