l1 b1 biology gcse

What is the odd one out and why?

B1. Characteristics of living organisms

Lesson Objective:1. List and describe the characteristics of living organisms.

What do you think you have in common with people of your age who live in the USA?

What do you think you have in common with an animal like a lion?

What do you think you have in common with a plant?

What do you think you have in common with bacteria?

Features of all living things are movement, respiration, sensing, growth, reproduction, excretion, and nutrition.

Characteristics of living organisms

- Respire- Irritability (Sensitivity)- Nourish- Grow and develop- Excrete- Reproduce

RINGER

Respiration

- Organisms use oxygen and nutrients to release energy

- Oxygen is generally gained from the environment and taken in by gaseous exchange systems

Irritability

• Organisms can detect changes to their environment

• If conditions are extreme organisms will have to move (or die)

Nutrition

• Organisms must take in food providing energy or materials for growth

• Plants use photosynthesis to make their own food

Growth

• Growth is a permanent increase in size and dry mass

• Organisms generally grow as time goes on

Excretion

• Removal of toxic waste from organisms

Reproduction

• Sexual – fertilization to produce a new organism

• Asexual – organism splits in two and produces two identical organisms

Questions

1. When did the first living organism appear on earth?

2. RINGER stands for what? 3. Give two reasons why reproduction is so

important for living organisms.