Q4 Biology 8 REVIEW

• Processes that release oxygen into the atmosphere:

  
  

  ● Ultraviolet rays from the sun disintegrate the ozone into oxygen

  ● Weathering of carbonate rocks (limestone & marble)

  ● Photosynthesis - produces oxygen through tiny leaves (stomata)

  ● Respiration - breathing IN oxygen & breathing OUT carbon dioxide of living things and even plants.
• Accessory Digestive Organs

  • Pancreas - produces digestive enzymes
  • Liver - produces "bile" that helps absorb fats and carry waste from the liver that cannot go through the kidney.
  • Gallbladder - storage for "bile" produced by the liver

  
• Diseases/Problems Involving the Digestive System

  • Pica - a compulsive eating disorder where people eat non-food things
  • Gastroesophageal Reflux Disease (GERD) - when acidic stomach juices/foods/fluids back up from the stomach to the esophagus. can affect asthma
  • Flatulence - releasing of gases
  • Indigestion - stomach acids break down the protective lining of the digestive system. leads to nausea and pain in upper abdomen
  • Colitis - inflammation of the inner lining of the colon. IBD, invasion of colon, or lymphocytic are a possible cause
  • Chronic Constipation - infrequent bowel movements/difficult passage of stools that persists for several weeks or longer.
• Stages of Mitosis

  1. Interphase - chromosome doubles or replicates itself because the DNA molecule contained in the chromosome produces an exact copy of itself

  2. Prophase - nucleus starts to disintegrate and ready for cell division

  3. Metaphase - nuclear membrane disappears; chromosomes align along the metaphase plate; spindle fibers form & attach to the centromeres of the chromosomes

  4. Anaphase - chromosomes move towards the opposite poles of the cells pulled by the spindle fibers

  5. Telophase - chromosomes are opposite places; a new nuclear membrane form around them & the spindle fibers disappear

  6. Cytokinesis - division of the cytoplasm, forming 2 separate daughter cells immediately after mitosis

  
• Importance of Cell Division

  Cell Division produces more cells in our body, helping growth and development of organisms. This helps in repairing tissue damage due to injuries/wear and tear. This renews cells in our body that are lost. Cell division also works in meiosis where the cells produce four daughter cells. It is important to take care of our body and the food we eat so that our cells may produce properly.
• Genotype


  Genetic composition of the person
• Phenotype


  Physical appearance or feature of the person
• Genotype

  • Homozygous Dominant - AA (both are dominant)
  • Homozygous Recessive - aa (both are recessive)
  • Heterozygous - Aa (mix of dominant and recessive; dominant masks off the recessive)
• Mouth


  breaks down the food for your body to absorb by chewing (mechanical digestion)
• Pharynx/Throat


  delivers the food to the esophagus
• Esophagus


  a tube-like structure that delivers the food to the stomach
• Stomach


  breaks down the food using enzymes/acid (chemical digestion)
• Small Intestine


  absorbs food molecules that have been broken down from the chemical digestion process
• Large Intestine


  receives the leftover material from the chemical digestion

  pushes the undigested food (feces) to the rectum
• Processes that release carbon dioxide into the atmosphere

  ● Respiration (releases it as waste product during energy production/breathing out)

  ● Decomposition of dead remains of living things

  ● Burning wood and fossil fuels like coal, oil, and natural gas
• Phosphorus Cycle


  moves through the lithosphere and hydrosphere

  are usually solid/liquid

  crucial for DNA, RNA, teeth, bones, and cell membranes

  Sources: bedrocks, organic deposits, tectonic activities