Science Vocab x

• How long does evolution take to occur?


  Millions of years
• What evidence suggests that humans and chimpanzees share a common ancestor?


  Fossils of different hominids show the evolution of humans over time
• What is a hominid?


  A human-like species
• What is a key feature that evolved in humans regarding locomotion?

  • Change from quadruped (four legs) to biped (two legs)
  • Advantages include:
  • Better visibility over obstacles
  • Requires less energy
  • Access to higher food
  • Ability to wade through deep water
  • Free hands for other uses
  • Increased agility and speed in some cases
• What are some advantages of bipedalism in humans?


  It allows for better visibility, requires less energy, and frees hands for other uses
• What significant change has occurred in human evolution regarding brain size?


  Humans have evolved larger brains
• What has the correlation between larger brains in humans led to?


  More complex use of tools and social interaction
• What does each pathogen require to be targeted by the immune system?


  A different antibody that will stick to it
• Why does it take time for lymphocytes to produce the correct antibody?


  Because they have to produce the specific antibody for each pathogen
• What are the main functions of the skeleton?


  1. Provide support for the body to keep us upright
  2. Protect vital organs
  3. Allow movement by working with the muscular system
  4. Produce new blood cells in the bone marrow
• What is the term for the point at which two bones meet?


  A joint
• How do muscles facilitate movement at joints?


  Muscles are attached to bones by tendons and work in pairs
• What are antagonistic pairs of muscles?


  Muscles that work in pairs to move a joint in opposite directions
• What happens when one muscle in an antagonistic pair contracts?


  The other muscle relaxes
• What are the components of a synovial joint?


  • Ligament: holds the bones together
  • Cartilage: protects the ends of the bones
  • Synovial fluid: lubricates the joint
  • Synovial capsule: produces and retains synovial fluid
• What is the role of cartilage in joints?


  It protects the ends of the bones to stop them rubbing together
• What condition may arise from the wearing away of cartilage over time?

  Arthritis
• What are the symptoms of arthritis?


  • Joint pain
  • Stiffness
  • Swelling
  • Reduced movement
• What is the function of synovial fluid in a joint?


  It lubricates the joint
• What does the synovial capsule do?


  It produces and retains synovial fluid
• How do fungi reproduce?


  By growing and then dividing into two.
• What do fungi need to grow?


  Food, warmth, and moisture.
• What diseases can fungi cause?


  They can cause diseases such as food poisoning and athlete's foot.
• How do fungi obtain their food?


  They decompose living or decaying tissue and use it as their food source.
• How do fungi reproduce in the air?


  By making dust-like spores that spread in the air.
• What is the role of viruses in disease?


  They invade living cells to reproduce, often destroying the cell in the process.
• What is an example of a disease caused by a virus?


  Influenza.
• What are the causes of diseases?

  • Infectious agents (e.g., bacteria, viruses)
  • Lifestyle choices (e.g., diet leading to diabetes)
  • Genetic factors (e.g., Down's syndrome from DNA abnormalities)
• What are the ways diseases can be transmitted?


  1. Touch (contact with someone or something)
  2. Air (e.g., sneezing)
  3. Water or food
  4. By animals (e.g., malaria via mosquitoes)
• What are the three lines of defence the body uses against disease?

  1. First line: Skin, mucus, tears
  2. Second line: Phagocytes (white blood cells)
  3. Third line: Lymphocytes and antibodies
• What is the function of the skin in the body's defence system?


  It stops microbes from entering the body unless cut or damaged.
• How does the respiratory system help defend against disease?


  Mucus and tiny hairs in the nose stop microbes from entering the lungs.
• What do tears contain that helps protect the eyes?

  Chemicals called enzymes that kill bacteria.
• What do phagocytes do in the body's defence system?


  They attack and engulf pathogens that enter the body.
• What is the role of lymphocytes in the immune response?


  They produce antibodies that mark pathogens for destruction.
• What do antibodies do to pathogens?


  They cause pathogens to stick together and mark them for destruction.
• Where does digestion begin in the human body?


  In the mouth
• What is the process of mechanically breaking down food in the mouth called?

  Digestion
• What is the term for taking in food?

  Ingestion
• What happens to food after it is swallowed?

  It travels down the oesophagus