Science

• Hypothesis:

  • An idea to explain an observation
  • In science, it must be testable, meaning it can be tested by a scientific enquiry like an experiment
  • Some hypotheses are untestable
• Prediction:

  • A guess, based on knowledge and understanding, at what might happen during an experiment or investigation
• Investigation:

  • A process to find something out, which may or may not involve an experiment
• Experiment:

  • A process in an investigation where a condition or variable is changed to observe its effects on other conditions or variables
• Variables:

  • Features investigated in an experiment
  • Three kinds:
  • The independent variable: the variable or condition that the scientist changes in the experiment
  • The dependent variable: the variable or condition that changes as a result of changing the independent variable
  • The control variable: the variable that affects the results of the experiment but is not investigated at that time, so it is kept constant
• Fair test:

  • An experiment where all variables are kept constant except the independent variable, allowing observation of its effect on the dependent variable
• Trend:

  • The gradual change in data from one value to another, such as numbers going up or down over time
• Pattern:

  • The repetition of a set of data over time
• Anomalous result:

  • A result that does not fit into a trend or pattern
• Data:

  • The collection of facts or measurements gathered during an investigation
  • Analyzed, evaluated, and used to draw conclusions
• Three important functions of a skeleton:

  • Supports the body
  • Facilitates movement
  • Protects organs
• Muscles can be distinguished from bones by:

  • Ability to contract and expand
  • Softness
  • No age limit
• Bones can be distinguished from muscles by:

  • Inability to contract and expand
  • Rigidity
  • Having an age limit
• A muscle is attached to two bones across a joint. When a muscle contracts, it exerts a pulling force, allowing the bones to move while the muscle stays stationary
• The place where bones meet is called a joint. Most joints allow some movement.

  • Examples of joints:
  • Fixed joints: e.g., skull and ribcage
  • Hinge joints: e.g., elbow and knee
  • Ball-and-socket joints: e.g., hip and shoulder
• Hinge joints can move forwards or backwards, while ball-and-socket joints can move backwards and forwards, side to side, and in circular movements
• Fixed joints are unable to move in any way
• The femur is the strongest bone in the body. It holds the hip and knee together, supporting the pressure and weight of the upper body
• 1. ray photographs of joints are taken to help plan a course of treatment, making it easier to identify issues