Donna Rae Siegfried

The human body is a beautiful and efficient system well worth study. In order to study and talk about anatomy and physiology, you need to start from an agreed-upon view of the human body. Anatomical position for the human form is the figure standing upright, eyes looking forward, upper extremities at the sides of the body with palms turned out.

The polymerase chain reaction (PCR) is a process that can turn a single copy of a gene into more than a billion copies in just a few hours. It gives medical researchers the ability to make many copies of a gene whenever they want to genetically engineer something. For years, the very structure of DNA made studying it rather challenging.

Although they're astoundingly varied, cells are also remarkably alike. All cells, at least all eukaryotic cells, are alike. Plants, animals, and fungi are eukaryotes (organisms made up of eukaryotic cells), and all their cells, in all their enormous complexity and variation, are fundamentally alike.Yes, your skin cells, your kidney cells, and your bone cells are fundamentally similar to the leaf cells and root cells of a carrot; the cells of a mold, mushroom, or yeast; and the single cell of microorganisms called protists that live in water and soil.

Biology is a very special application of the laws of chemistry and physics. Biology follows and never violates the laws of the physical sciences, but this fact can sometimes be obscured in the complexity and other special characteristics of biological chemistry and physics.Following is a review of some of the principles of chemistry and physics that have special application in anatomy and physiology.

Even when your outside is staying still, your insides are moving. Day and night, your muscles twitch and contract and maintain "tone." Your heart beats. Your blood circulates. Your diaphragm moves up and down with every breath. Nervous impulses travel. Your brain keeps tabs on everything. You think. Even when you're asleep, you dream (a form of thinking).

Your body's reactions that convert fuel (specifically glucose) to usable energy (ATP molecules) include glycolysis, the Krebs cycle (aerobic respiration) and anaerobic respiration, and oxidative phosphorylation. Together, these reactions are referred to as cellular respiration.These are complex pathways, so expect to take some time to understand them.

The organs of the female reproductive system are concentrated in the pelvic cavity. Many of the female reproductive organs are attached to the broad ligament, a sheet of tissue that supports the organs and connects the sides of the uterus to the walls and floor of the pelvis. Ovaries The ovaries are two almond-shaped structures approximately 2 inches (5 centimeters) wide, one on each side of the pelvic cavity.