GCSE Biology - Characteristics of Living Things (Organisms) #3

Summary

This video script explores the seven defining characteristics of living organisms, using the acronym 'MRS GRAN' to remember them: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition. It clarifies that while non-living things may exhibit some of these traits, only living things possess all seven. The script also distinguishes that viruses, despite being commonly referred to as organisms, do not meet the criteria for being considered living due to their inability to grow and excrete waste.

Takeaways

• 🧬 All living organisms share seven key characteristics, which can be remembered using the acronym 'MRS GRAN'.
• 🚶 Movement is the ability of organisms to change their position, either as a whole or in part.
• 🔥 Respiration is the process of breaking down nutrients to release energy for metabolism.
• 🌡️ Sensitivity is the ability to detect and respond to changes in the environment, which can also be viewed as an organism's control over its internal environment.
• 🌱 Growth is a permanent increase in size and dry mass, which can vary from organism to organism.
• 🐾 Reproduction is the process by which organisms create more of their kind, such as cats having kittens or bacteria dividing.
• 🚰 Excretion is the removal of waste products from metabolism and excess substances that are not needed.
• 🍽️ Nutrition is the intake of materials necessary for energy, growth, and development, which can be through eating, drinking, diffusion, or active transport.
• 🔬 Living organisms are composed of one or more cells, which will be discussed in a separate video.
• 🦠 Viruses are not considered living organisms as they do not meet all seven of the characteristics, such as the inability to grow over time and excrete waste.
• 📚 The video encourages viewers to visit a revision site for practice questions on science and math topics.

Q & A

What are the seven key features that all living organisms have in common?

The seven key features are movement, respiration, sensitivity, growth, reproduction, excretion, and nutrition.

What is the acronym used to remember the seven key features of living organisms?

The acronym used is 'MRS GREN'.

Can non-living things exhibit some of the features of living organisms? Provide an example.

Yes, non-living things can exhibit some of these features. For example, a crystal can grow and a car can move.

What does the feature 'movement' refer to in living organisms?

Movement refers to the ability of organisms to move. This could be the whole organism, like a cow moving its body, or parts of an organism, like a plant turning its leaves towards the sun.

What is respiration in the context of living organisms?

Respiration is a set of chemical reactions that occur in cells to break down nutrient molecules like sugars and release energy for metabolism.

What does 'sensitivity' mean for living organisms?

Sensitivity refers to the ability to detect and respond to changes in the internal or external environment. This can involve detecting changes like temperature and responding to them by actions like sweating or shivering.

How is growth defined for living organisms?

Growth is defined as a permanent increase in size and dry mass. This can be seen in organisms growing larger, such as a kitten growing into an adult cat or a bacteria increasing in size.

What is the process of reproduction in living organisms?

Reproduction is the process of making more of the same kind of organism, such as a cat having kittens or bacteria dividing into two smaller bacteria.

What does excretion refer to in living organisms?

Excretion refers to the removal of waste products of metabolism and substances that are in excess of requirements, like urea and carbon dioxide, as well as excess water and mineral ions.

How do living organisms obtain nutrition?

Nutrition involves taking in materials for energy, growth, and development. For animals, this means eating and drinking, while for fungi or bacteria, it means absorbing nutrients from their surroundings.

Why are viruses not considered living organisms?

Viruses are not considered living organisms because they do not meet the seven requirements for living things, such as growth over time and excretion of waste.

What is metabolism?

Metabolism refers to all the chemical processes that occur within an organism to keep it alive, including all the reactions happening inside the organism.

What is the significance of cells in living organisms?

All living organisms are made up of one or more cells, which are the structural units of life. This will be explored further in another video.