Science Final Exam Revision Worksheet: Digestive System, Forces, and Adaptations

The Starting Point of Digestion: Digestion begins in the mouth. This is where food is broken down into tiny pieces via mechanical and chemical processes.
The Oesophagus: This organ is the tube that connects the mouth to the stomach. Its primary function is a transit process where food is pushed down toward the stomach.
The Stomach: In the stomach, food is mixed with digestive juices. This process transforms the food into a thick liquid.
The Small Intestine: The function of the small intestine is to move nutrients into the blood. It acts as the primary site for nutrient absorption.
The Large Intestine: This organ is responsible for removing excess water from undigested food and absorbing it back into the body.
The Anus: The final part of the digestive tract, responsible for removing undigested food (faeces) from the body.

Carbohydrates: These provide the body with its primary source of energy. Examples include pasta and bread.
Proteins: This food group is used by the body for growth and to build up muscles. Examples include fish, meat, and butterbeans.
Fats: Provide a concentrated source of energy and help insulate the body.
Vitamins and Minerals: These are essential for maintaining health. Specific minerals mentioned include:
- Calcium: Important for bone and teeth strength.
- Iron: Essential for blood health.
Water: A critical component of a balanced diet that helps to move nutrients through the body.
Fibre: Essential for healthy digestion and moving waste through the system.
The Balanced Diet: A balanced diet must include all of the following: carbohydrates, fats, proteins, minerals, vitamins, water, and fibre. It is incorrect to say a balanced diet should exclude all fats or all sweets; rather, it requires a balance of all nutrients.

Case Study: Butterbeans vs. Creamed Corn:
- Most Protein: Butterbeans contain more protein than creamed corn.
- Most Sugar: Creamed corn contains more sugar than butterbeans.
- Dominant Nutrient in Creamed Corn: Carbohydrates are the primary nutrient found in creamed corn, which function to provide energy.
- Minerals Identified: Calcium and Iron are both found in these canned foods.
Product A vs. Product B Comparison:
- Sugar Content: Product B contains the highest amount of sugar per serving.
- Sodium Content: Product A contains the least amount of sodium per serving.
- Protein Equality: While both products may have the same amount of protein, the protein's function remains helping the body grow and build muscle.

Gravity: A force that pulls all objects toward the center of the Earth. In force diagrams, it is represented by an arrow pointing downwards.
Friction: A force that opposes motion between surfaces that are touching. For example, friction acts between the tires of a car and the road surface.
Air Resistance: A type of friction specifically acting on objects moving through the air, such as a kite flying in the sky or a skydiver with a parachute.
Water Resistance: A force that opposes the motion of objects through water, such as a swimmer or a shark moving through the sea.
Upthrust: The force that pushes an object up when it is placed in a fluid (liquids or gases).
Thrust: A force that pushes an object forward.
Normal Force: A support force exerted upon an object that is in contact with another stable object.
Balanced forces: These occur when the forces acting on an object are equal in size and opposite in direction, resulting in no change in motion.

Magnetic Attraction: A magnet attracts other magnets or magnetic materials by pulling them toward itself.
Magnetic Repulsion: When two magnets are brought close together with the same poles facing each other (North-North or South-South), they repel each other.
Magnetic Materials: Materials that are attracted to a magnet. Examples include:
- Steel
- Iron
Non-Magnetic Materials: Materials that cannot be attracted to a magnet. Examples include:
- Wood
- Copper
- Plastic
- Aluminium

Arun and Marcus Investigation: Comparing the strength of two magnets using a plastic ruler and a steel drawing pin.
- Independent Variable: The strength of the magnets being tested.
- Dependent Variable: The distance at which the steel drawing pin is attracted to the magnet.
- Control Variable: The object being attracted (the steel drawing pin).
- Reasoning for Materials: Steel is used for the drawing pin because it is magnetic. Plastic is used for the ruler because it is non-magnetic and will not interfere with the magnetic attraction.
- Identifying Strength: In this investigation, the stronger magnet is identified by its ability to attract the drawing pin from a greater distance.

Streamlined Shape: A shape designed to reduce water or air resistance.
- Submarines: Feature a streamlined shape to reduce water resistance and increase speed through the water.
- Sharks: Their streamlined body shape allows them to move quickly through the water for hunting.

Rotation: The Earth turns on its own axis. This rotation takes $24\,\text{hours}$ and is the direct cause of day and night.
Revolution/Orbit: The Earth moves around the Sun in an orbit. This process takes $1\,\text{year}$ (approximately $365.25\,\text{days}$ ).
The Axis: An imaginary line that runs through the Earth from the North Pole to the South Pole.
Winter: Occurs when the area in which you live tilts away from the Sun.
Day and Night: When one side of the Earth faces the Sun (Day/ $X$ at the middle of the day), the opposite side of the Earth is experiencing night.

Definition of Adaptation: A trait that helps a plant or animal survive in its specific environment.
Plant Adaptations for Dry Climates:
- Roots that grow deep into the ground to find water.
- Thick stems capable of storing water.
Hibernation: An adaptation that allows animals to conserve energy and survive when food sources are scarce.
Polar Bear Adaptations:
- Environment: Thick fur and a layer of fat for insulation against extreme cold.
- Predatory Traits: Forward-facing eyes for depth perception, large/sharp claws, an excellent sense of smell, and white fur for camouflage in the snow.

Defense Methods:
- Staying in Groups: Used by Springboks and Wasps to deter predators.
- Eyes on Sides of Head: Used by Rabbits to provide a wide field of view for spotting predators.
- Protective Shells: Tortoises pull their heads inside their shells for protection.
- Camouflage and Speed: Used by Rabbits to avoid detection or escape.
Attack Methods:
- Horns: Used by Buffalo as a weapon.
- Stingers: Used by Jellyfish.
- Ink Spraying: Octopuses spray ink to cover a predator and escape quickly.
- Sharp Teeth and Claws: Found in apex predators like Polar Bears.