Week 5-9

• Basic Parts of a Microscope

  • Eye Piece
  • Objective Lens
  • Total
• Total Magnification

  The greater the magnification, the smaller the field of view, but sample can be seen in greater detail
• Field of View

  • The amount of a sample that you can see through a microscope
  • Greater magnification, lower FOV
  • Lower magnification, higher FOV
• Converting mm -> µm

  1. 1mm = 1000µm (x1000)

  2. 1µm = 1/1000mm (/1000)
• Scale Bar
• Nucleus

  • Houses the cell's genome – contains genetic information
  • The nucleus is the cell's control centre
• Cell Membrane

  • Provides a fixed environment inside the cell
  • Transport nutrients into the cell
  • Transport toxic substances out of the cell
• Cell Wall

  • Surrounds the cell membrane (plant cells only)
  • Provides strength and protection against mechanical and osmotic stress
• Mitochondria


  • Powerhouses of the cell
  • Breakdown food molecules to turn into sugar through a process called cellar respiration
• Chloroplast


  • Within the cells of plants and certain algae
  • Controls the process of photosynthesis - sunlight converted into chemical energy
• Vacuole

  Stores water and nutrients for the cell
• Cilia


  • Small, slender, hair-like structures present on the surface of all mammalian cells
  • Beat in waves to propel inhaled particles trapped in the mucous layer out of the airways
• Pili


  • Short, hair-like structures on the cell surface of prokaryotic cells
  • Attach a bacterial cell to specific surfaces or other cells
• Flagellum

  • Microscopic hair-like structures involved in the locomotion of a cell
  • Whip-like appearance that helps to propel a cell through the liquid
  • Used sometimes as sensory organs that can sense changes in pH and temperature
• Main Nutrients

  • Carbohydrates
  • Protein
  • Fats
  • Vitamins and Minerals
• Carbohydrates


  • Body's main source of nutrients
  • Fuel your brain kidney, heart, muscles, and central nervous system
  • Examples: pasta, bread, rice
• Protein


  • Used to build and repair muscles and bones
  • Create hormones and enzymes for the body
  • Examples: fish, beef, chickpeas
• Fats


  • Gives body energy and support
  • Protect organs by cushioning them and giving them warmth
  • Examples: butter, avocado, egg
• Vitamins and Minerals

  • Houses the cell's genome – contains genetic information
  • Examples: water, vitamin c, vitamin d
• Digestive System Diagram
• Organs in Digestion

  • Mouth
  • Oesophagus
  • Stomach
  • Small Intestine
  • Large Intestine
  • Rectum
  • Pancreas
  • Liver
  • Gall Bladder
• Mouth


  • Moisten foods so food can move easily through the oesophagus and into your stomach
  • Saliva glands make saliva - a digestive juice that breaks down food in the body
• Oesophagus


  • Transport food entering the mouth through the throat and into the stomach
  • They are muscles that push the material down your body (peristalsis)
• Stomach

  • Strong muscular walls that hold food and mix it with enzymes
  • Acids continue to break down the food into a liquid or paste (bile)
• Small Intestine


  • Helps to further digest food and absorb nutrients and water needed for the body
  • Gets rid of unnecessary components
• Large Intestine

  • Absorbs water and electrolytes
  • Broader path than the small intestine
• Rectum


  • Excrete waste from leftover food
  • End of digestion tract
• Pancreas

  • Produces enzymes that help digest food
  • Pancreatic hormones regulate blood sugar levels and stimulate stomach acids
• Liver

  • All blood leaving the stomach and intestine passes the liver
  • Processes blood and breaks down, balances, and creates nutrients
• Gall Bladder


  • Stores bile, a thick liquid that's produced by the liver to help us digest fat
  • Thin, muscular lining squeezes bile into the small intestine through the main bile duct
• Delivery of Nutrients

  As food passes through the digestive tract, it mixes with digestive juices, causing large molecules of food to break down into smaller molecules. The body absorbs these smaller molecules through the walls of the small intestine into the bloodstream, which delivers them to the rest of the body
• Survival of Organisms

  Unlike plants which use photosynthesis to produce energy – animals must gain energy through a different process. The digestive system breaks down food into simple foods such as carbohydrates, fats, and proteins. These can then be absorbed into your blood to be used for energy, growth, and repair
• Absorption

  The broken-down food is absorbed into the bloodstream from the small intestine and the nutrients are carried to each cell in the body. This comes after the breakdown of carbohydrates, proteins, fats, vitamins, and minerals, which are essential for energy production, growth, and cellular maintenance
• Diffusion

  Fats, vitamins, and glucose can move into the bloodstream by diffusion. These molecules diffuse from the small intestine into the blood, moving from higher to lower concentration. Water will move in the direction where there is a high concentration of solute
• Herbivores vs Carnivore Digestive Systems

  • Herbivores
  • Carnivores
• Herbivores

  These animals have broad, flat, and short, teeth to grind and chew plant leaves, grains, and seeds. Most herbivores have several stomach chambers and a comparatively longer digestive tract than carnivores. They have a special stomach to digest the increased cellulose present in grass. Cellulose is a hard substance to digest
• Carnivores


  Has a shorter digestive tract. This is because meat is dense in nutrients, and they can extract these nutrients more easily
• Egestion


  • Process eliminates indigestible components and harmful substances from the body
  • Examples: waste and toxins
• Circulatory System Diagram
• Major Structures in the Circulatory System

  • Right atrium
  • Left Atrium
  • Right Ventricle
  • Left Ventricle
  • Valves
  • Aorta
  • Vena Cava
  • Pulmonary Artery
  • Pulmonary Vein