Search Results

Mechanisms of capillary exchange

By: HWC, Views: 7892

■ The primary role of capillaries is to permit the exchange of nutrients and wastes between the blood and tissue cells (via interstitial fluid). ■ Oxygen and nutrients move from the blood to the cells. ■ Carbon dioxide and other wastes move from the cells to the blood. The three ba...

SNP Polymorphysim Microarray Chip - How to Test a Person's DNA

By: HWC, Views: 7050

To test a person's DNA, a researcher first needs a source of tissue. Most of the cells in a blood sample are red blood cells, which lack nuclei, but there are also a number of white blood cells, which do contain nuclei and chromosomal DNA. If we could see a particular DNA sequence in these cel...

Nervous pathway to the Neuromuscular (NMJ)

By: HWC, Views: 8288

• A nervous impulse, also called an action potential, starts from the brain or spinal cord to signal skeletal muscle cell contraction. Action potentials continue along a motor neuron to the muscle cell. • The signal to contract must cross a synapse - the neuromuscular junction (NMJ) - betwe...

Brain Anatomy Animation (Part 2 of 2)

By: Administrator, Views: 11976

Its nervous tissue consists of millions of nerve cells and fibers. It is the largest mass of nervous tissue in the body. The brain is enclosed by three membranes known collectively as the meninges: dura mater arachnoid pia mater The major structures are the: cerebrum cerebellum dienc...

B cells and antibodies

By: HWC, Views: 8525

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...

Labor and Delivery - Placenta Cord

By: Administrator, Views: 350

Soon after a baby is conceived, a support system, comprised of the placenta and umbilical cord, begins to develop. These two structures are essential for sustaining a healthy pregnancy, explains Donald Davis, an obstetrician in Medicine Hat, Alta., and past president of the Society of Obstetricia...

Pressure Flow Model Animation

By: HWC, Views: 7012

This apparatus of beakers A and funnels simulates the flow of a sucrose solution in the phloem of a plant. The funnels and connecting tube represent a sieve tube of the phloem. Differentially permeable membranes cap the funnels at the source and sink ends, allowing water, but not sucrose, to cros...

Alzheimer's Disease

By: Administrator, Views: 10898

Alzheimer's disease (AD), also referred to simply as Alzheimer's, is a chronic neurodegenerative disease that usually starts slowly and gradually worsens over time. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the d...

Introduction to Breast Cancer

By: Administrator, Views: 10370

Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, fluid coming from the nipple, a newly inverted nipple, or a red or scaly patch of skin. In those with distant spread of the disease, t...