Search Results

Global warming and its effect on climate change

By: HWC, Views: 6298

Global warming, habitat destruction, and pollution are all hot topics in the news. Environmentalists are concerned that many of these factors will lead to the loss of species. But how will this happen? One way to think about the environment is as a finely-tuned, high performance engine. If one...

Flexor reflex & Crossed extensor reflex

By: HWC, Views: 6585

• The flexor reflex is a response to pain. This reflex is polysynaptic, ipsilateral, and intersegmental. • Pain receptors are stimulated causing increased frequency of action potentials to be generated and conducted along the sensory neuron axon. • The sensory impulses excite several ass...

Predator- prey competition and symbiosis

By: HWC, Views: 6479

Predator-prey relationships occur when one species, the predator, kills and eats an organism of another species, the prey. This graph shows the cyclical nature of predator-prey relationships, in this case among populations of Canada lynx and snowshoe rabbits. If predation is without some li...

Stretch reflex & Tendon reflex

By: HWC, Views: 6383

• The stretch reflex is a response to the stretching of muscles. It is monosynaptic and ipsilateral. • Stretching stimulates receptors in the muscle spindle of the agonist (stretched) muscle. • One or more action potentials are generated by the receptors and propagate along the axon of ...

Major Elements in Biological Molecules: Lipids

By: HWC, Views: 5916

A triglyceride (also called triacylglycerol) is composed of three fatty acid molecules and one glycerol molecule. The fatty acids attach to the glycerol molecule by a covalent ester bond. The long hydrocarbon chain of each fatty acid makes the triglyceride molecule nonpolar and hydrophobic. Pa...

How do the different types of chromatography work? (No Audio)

By: HWC, Views: 5984

Chromatography is a term for a variety of techniques in which a mixture of dissolved components is fractionated as it moves through some type of porous matrix. A glass column is filled with beads of an inert matrix. The mixture of proteins to be purified is dissolved in a solution and passed ...

System organization - PPM system types (Somatic, Autonomic & Enteric) and Reflex arc types

By: HWC, Views: 6804

• The PNS consists of all nervous tissue outside of the CNS. • It is divided into three functional components: • Somatic nervous system (SNS) • Autonomic nervous system (ANS) • Enteric nervous system (ENS) • The SNS consists of: • Sensory neurons from skeletal muscles ...

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

By: HWC, Views: 5952

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...

Replication of DNA and Chromosomes/ How do cells replicate their DNA? (Animation) no Audio

By: HWC, Views: 6386

DNA replication in E. coil begins at a site called oriC where a replication bubble forms. At either end of this bubble is a replication fork. Since DNA polymerase Ill can read its DNA template strand only in the 3' to 5' direction this means that one strand (leading) can be read continuously b...