Man The Incredible Machine: NGS

  1. Our bodies are made of @ 2/3 water, carbon, calcium, and other elements. Our skin has as many hair follicles as do our cousins the chimpanzees. The outer layer of skin is dead it is constantly replaced by living cells beneath. The process takes @ a month. The skin is the largest organ of the body and weighs @ six pounds. The finger tips have @ 2,000 pores per square inch. The skin is a sense organ (cutaneous sensations).
  2. Humans have @ 2 million sweat pores on the surface of the body. Perspiration evaporates cooling the body. We put out @1 to 2 pints a day.
  3. Humans are for the most part visual animals. Our eyes blink once every 2 to 10 seconds and as a result are closed several hours per day. Retinal image formation is upside down the brain interprets the information so the we see right side up.
  4. The human ear can distinguish @ 1,600 frequencies. Sound is vibrating air and is transmitted through the ear drum to the malleus to the incus to the stapes to the cochlea where we have specialized nerve cells that perceive sound. The semi-circular canals of the inner ear allow us to balance.
  5. About a pint of air enters the body with each breath. This happens @ 14 times per minute. The diaphragm pulls down and the chest walls expand lowering pressure in the lung cavity. When the pressure drops below atmospheric pressure air rushes in. The alveoli of the lungs (clusters of small grape-like sacs) are site of oxygen carbon dioxide exchange. Capillaries around the alveoli allow for the exchange. There are @ 300 million alveoli that make up the structure of the lings.
  6. The circulatory system with its 60,000 miles of blood vessels transports the respiratory gasses as well as nutrients to the cells of the body. We have a closed
    circulatory system. The blood flow goes from the heart into the arteries to the capillaries to the veins and then back to the heart.
  7. The immune response is the bodies specific resistance to disease. T and B lymphocytes are the major cells involved.
  8. Fish have two chambered hearts. Amphibians and reptiles have three chambered hearts. Birds, mammals, and dinosaurs have four chambered hearts. The heart
    chambers have three layers of tissue. The human heart pumps @ 2,000 gallons a day and @ 55 million gallons during the human life time.
  9. Muscles make up @ 40 % of body weight and bones make up @ 18 %. Muscles contract and produce movement by working in antagonistic pairs or groups. There are @ 600 muscles in the human body and 206 bones. Muscles generate motion by pulling on bones. Running generates @ 5,000 lbs/sq. inch pressure and jumping as much as @ 20,000 lbs/sq. inch. The hands have 25 joints and produce 58 separate and distinct motions.
  10. Human females are born with @ 1/2 million eggs. They ovulate @ 400 + during their life time. Males produce @ 200 million sperm daily. When fertilization occurs a zygote is formed this develops into a blastula then a gastrula, then an embryo, then a fetus and finally an infant. Human gestation is normally nine months. After fertilization it takes @five days for implantation to occur. Completion of form takes place in @ 980 days.