science

• digestive system - the organs that break down food into smaller pieces and absorb nutrients and also excrete waste
• mechanical - grind/pound the food
• chemical - break down into smaller pieces
• mouth - beginning of the digestive system
• teeth - used for chewing BOLUS food mixed with saliva
• esophagus - delivers food
• stomach - stores food

  • upper portion - fundus
  • lower porting - antrum
• tounge - muscle covered with a mucous membrane
• saliva - can be found in mouth

  • parotid
  • sublingval
  • submandibular glands
• peristalsis - involuntary contruction and relaxation of longitudinal
• small intestine

  • duodenum - foot long
  • jejunum - 8 feet
  • ilelium - 12 feet
• carbohydrates - fuel or energy
• fiber - vitamins and minerals

  insoluble
• protein - builds muscle
• water/beverages - 8-10 servings
• grains - 6-8 servings
• vegetables and fruits - 3 servings
• meat, poultry, fish, beans, eggs - 2-3 servings
• cell cycle - the series of events that occur in a cell to produce a new cell
• s/synthesis phase - duplication of DNA
• chromosomes - filled with DNA
• DNA

  • deoxyribunucleic acid
  • it has our blue print
• 2 types of cell

  1. body cells - somatic
  2. sex cells - sperm and egg cell
• mitosis - occurs in body cell
• prophase

  • nuclear membrane disingregate
  • centrioles appear & moves to the pole
  • spindle fibers appears
• metaphase

  • chromosomes line up in the metaphase region
• anaphase

  • chromosomes are pulled towards the pole
  • spindle fibers shortens
  • chromosomes breaks apart
• telophase

  • cleavage furrow occurs
  • spindle fiber disappear
  • nuclear membranes reappears
• meiosis - type of cell division that takes place during the creation of sex cells
• diploid cell (2N)
• haploid (N)
• male - spermatogenesis
• female - oogenesis
• creation of sperm cells happens in the testes while egg cell reproduction happens inside the ovary
• father & mother 23 chromosomes
• zygote 46 chromosomes
• spermatogenesis - refers to the production of spermatozoa called sperms which occur inside the testes
• reproductive cell also known as spermatogonium
• oogenesis

  • refers to the creation of gametes called ova which happens inside the ovaries
  • reproductive female cells known as oogunium
  • begins in meiosis 1