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Mendel's Principles of Inheritance (Father of Genetics)

By: HWC, Views: 7506

Gregory Johann Mendel, a monk living in the mid-1800's, is known as the "Father of Genetics" for his experiments with pea plants in the abbey garden. These experiments led him to deduce the fundamental law of genetics. Mendel was an Augustinian friar who entered, in 1843, the Abbey of St. Thom...

Natural Selection, Species Isolation and Real World Example

By: HWC, Views: 7311

`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 ...

Pasteur's Experiment

By: HWC, Views: 7248

Louis Pasteur designed a procedure to test whether sterile nutrient broth could spontaneously generate microbial life. To do this, he set up two experiments. In both, Pasteur added nutrient broth to flasks, bent the necks of the flasks into S shapes, and then boiled the broth to kill any existing...

Ear Virtual Tour Animation

By: Administrator, Views: 10874

The ear is the organ of hearing and, in mammals, balance. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of the pinna and the ear canal. Since the outer ear is the only visible portion of the ear in most ani...

HIV Infection: Viral life cycle

By: HWC, Views: 7227

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...

Apicomplexan life cycle Animation

By: HWC, Views: 2190

Malaria is caused by the sporozoan, Plasmodium. It is transferred to humans by mosquitoes. When an infected mosquito feeds, infective sporozoites move from her salivary glands into the human body. The bloodstream carries the sporozoites to the liver. Here, they reproduce asexually and...

The life cycle of protein

By: HWC, Views: 7523

The life cycle of a typical protein begins with its synthesis on a ribosome. As the polypeptide chain grows, molecules of a chaperone protein bind along its length. This prevents misfolding of the nascent polypeptide. ATP binding causes chaperone release. For most proteins, the polypeptide th...

Gastrulation: cross section of the frog

By: HWC, Views: 6937

Gastrulation Most animals enter a phase early in development called gastrulation. In this phase, a tiny ball or disc of cells rearranges to form three embryonic layers of tissue, called germ layers. The germ layers of the embryo—now called a gastrula—are called the endoderm, mesoderm, and eco...

Structures that affect circulation - heart and systolic/diastolic BP

By: HWC, Views: 7811

• Heart generates blood pressure. • Arterioles produce resistance thereby regulating blood flow to tissues. • Veins store blood; kidneys regulate blood volume; both affect venous return and cardiac output. ■ Contractions of the ventricles determine blood pressure, which drives th...