Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The 7 Life Processes: All living things carry out seven essential processes, often remembered by the acronym MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.
Movement: Living things can move their body parts. Animals move to find food or shelter, while plants move toward sunlight (e.g., ).
Respiration: This is the chemical process where living cells release energy from food. It often involves taking in and releasing .
Sensitivity: Living things can detect and respond to changes in their environment (stimuli), such as light, heat, or sound.
Growth: Living things increase in size or complexity over time. For example, a seed grows into a plant.
Reproduction: The ability to produce offspring (babies or seeds) to ensure the survival of the species.
Excretion: The process of getting rid of waste products from the body, such as urine or .
Nutrition: Living things need food for energy. Plants make their own food through , while animals eat plants or other animals.
Classification: Objects are classified into three categories: Living (shows all MRS GREN), Non-living (never lived), and Once-living (dead materials like a wooden chair or a leather belt).
📐Formulae
💡Examples
Problem 1:
A car can move, it takes in fuel (nutrition), and it releases exhaust gases (excretion). Is a car a living thing? Explain why.
Solution:
No, a car is a non-living thing.
Explanation:
To be classified as living, an object must show all seven life processes of MRS GREN. While a car moves and uses fuel, it cannot grow or reproduce on its own.
Problem 2:
Is a piece of paper considered living, non-living, or once-living?
Solution:
Once-living.
Explanation:
Paper is made from wood, which came from a tree. Since the tree was a living thing that performed processes like , the paper is classified as once-living (dead).
Problem 3:
Name the gas that most living things need to take in for respiration and the gas they release as waste.
Solution:
Take in: (Oxygen); Release: (Carbon Dioxide).
Explanation:
During respiration, cells use to break down nutrients and produce energy, resulting in as a byproduct.