Animal & Plant systems

• Digestion


  1. Ingestion

  2. Digestion

  3. Absorption

  4. Elimination/egestion
• Physical digestion


  Breaking down large pieces of food into smaller pieces to increase surface area
• Chemical digestion


  Breaking down complex molecules into simpler molecules involving enzyme activity
• Oral cavity


  • Teeth ~ mechanical/physical digestion
  • Salivary ~ chemical digestion
• Oesophagus


  • Food travels from mouth to stomach
  • Peristalsis: involuntary wave-like muscle contractions which move food along the digestive tract
• Stomach


  • Food : Storage and disinfection
  • Chemical and mechanical digestion ~ churning and enzymes (pepsin~proteins, lipase~fats)
• Small intestine - Chemical digestion


  • Pancreas makes digestive enzymes which are transported to small intestine
  • Lipase breaks down fats into fatty acids
  • Trypsin breaks down protein into amino acids
  • Carbohydrase breaks down carbohydrates into glucose
• Small intestine - Absorption


  • Long w/ specialised surface containing millions of villi which increase the surface area of the small intestine
• Large intestine

  • final absorption of water, vitamins, and minerals
  • food becomes more solid and compact, turns into faeces
  • Large number of bacteria which help with digestion and release gas as a result
• Excretory system


  • made up of a number of organs and tissues used to remove toxins from the blood
• Urinary tract


  • Kidneys
  • Ureters
  • Bladder
  • Urethra
• Liver


  • Detoxifies a variety of harmful chemicals ~ alcohol and drugs
  • Responsible for breaking down amino acids to release ammonia
  • Breaks down worn-out red blood cells, producing bile
• Kidneys


  • maintain balance of water
  • filter toxic substances from the blood stream
• Nephron


  • functional unit of the kidney
  • removes waste and excess substances to make urine
  • blood filter
• Nephron parts

  Glomerulus

  Bowman's capsule

  Proximal convoluted tubule

  Loop of Henle

  Distal convoluted tubule

  Collecting tubule
• Glomerulus 


  FILTRATION

  pressure forces small substances through the capillaries into bowman's capsule

  pink
• Bowman's capsule


  FILTRATION

  collects filtrate from glomerulus and filters it into the proximal convoluted tubule

  orange
• Proximal convoluted tubule


  REABSORPTION

  substances like glucose, calcium, sodium and amino acids get transported back into the capillaries

  purple
• Loop of Henle


  REABSORPTION

  water gets reabsorbed into the capillaries via osmosis

  blue
• Distal convoluted tubule


  REABSORPTION

  optional ~ of water and ions

  yellow
• Collecting tubule


  SECRETION

  waste products are transported through while water is continually absorbed until secretion

  green
• Xylem


  one way transportation of water, potassium, nitrogen & phosphorus from the roots to the leaves of the plant

  dead tissues (x=dead)
• Phloem


  two way transportation of water and other nutrients like sugar around a plant

  living tissue
• Root hair cells


  finger-like projections that increase SA:V ratio

  therefore increasing absorption
• Transpiration


  evaporation of water from leaves & movement of liquids up the xylem

  FACTORS EFFECTING TRANSPIRATION RATE:

  • temperature
  • light
  • humidity
  • wind
  • water availability
• Translocation


  movement of nutrients created in leaves to other areas of the plant
• Stomata


  small pores on a leaf's surface that open and close to regulate gas exchanges
• Opening stomata and increased rate of transpiration

  potassium enters guard cells causing osmosis therefore making them turgid and opening the stoma

  water vapour can leave

  CO2 can enter as an input of photosynthesis

  O2 can exit after it is created during photosynthesis
• Closing a stomata and decreased rate of transpiration

  potassium pumped out of guard cells, causing water to move and creating flaccid guard cells.

  stomata closes therefore gasses cannot leave or enter