MRS GREN Flashcards
What do each of the letters in MRS GREN stand for?
Movement Respiration Sensitivity Growth Reproduction Excretion Nutrition
What is the definition of respiration?
Cells use oxygen to react with glucose to produce energy and to produce carbon dioxide and water as by-products (occurs in the mitochondria)
Where does respiration occur in a cell?
In the mitochondria
What are the reactants of respiration?
Glucose and oxygen
What are the products of respiration?
Carbon dioxide and water
What are the by-products of respiration?
Carbon dioxide and water
Is respiration the same as breathing?
No - breathing means inhaling oxygen and exhaling carbon dioxide using the lungs, respiration is cells using oxygen to react with glucose to produce energy and to produce carbon dioxide and water as by-products (occurs in the mitochondria)
What is the word equation for respiration? How does this relate to the photosynthesis equation?
Oxygen + glucose –> Carbon dioxide + water + energy
It is the opposite of the photosynthesis equation (energy comes from sunlight in photosynthesis:
Carbon dioxide + water + sunlight –> Oxygen + glucose)
What time of day does respiration happen?
All the time
In which kingdoms does respiration occur?
All of them - it is part of MRS GREN
How many of the MRS GREN characteristics must an organism possess to be living?
All of them
MRS GREN are the characteristics of …
All living organisms
Differences between photosynthesis and respiration
- Respiration occurs in all living cells in all kingdoms, photosynthesis only occurs in plant cells
- Respiration occurs in mitochondria and does not involve chlorophyll, photosynthesis occurs in chloroplasts and involves chlorophyll
- In photosynthesis, carbon dioxide and water are the reactants, whilst in respiration, oxygen and glucose are the reactants
- In respiration, carbon dioxide and water are the products, whilst in photosynthesis, oxygen and glucose are the products
- Photosynthesis is the opposite of respiration
- Respiration does not need sunlight to occur, photosynthesis does need sunlight to occur
- In respiration, energy stored in glucose is released, in photosynthesis, energy in sunlight is stored in glucose
Give examples of each of the MRS GREN characteristics for plants
Movement - move towards sunlight
Respiration - respire the glucose produced in photosynthesis to release energy for other life processes
Sensitivity - e.g. venus fly trap responds to touch, plants sense direction of sunlight and grow towards it, roots of plants sense sunlight and grow away from it (and sense gravity downwards and grow towards it) further into the soil
Growth - grow from seeds into plants using energy released in respiration
Reproduction - produce new seeds for new plants
Excretion - e.g. remove oxygen (waste product from photosynthesis) and carbon dioxide and water (waste products from respiration) through the stomata
Nutrition - obtain nutrients/food (glucose) through photosynthesis, absorb nutrients and mineral ions from soil through roots
Give examples of each of the MRS GREN characteristics for animals
Movement - escaping from predators
Respiration - respire the glucose gained through consuming producers (plants) to release energy for other life processes
Sensitivity - 5 senses and responding to them - touch, hearing, smell, taste, sight
Growth - grow from baby to adult using energy released in respiration
Reproduction - giving birth to new baby animals
Excretion - e.g. removing carbon dioxide (waste product from respiration) by breathing out
Nutrition - obtain nutrients/food (glucose) through consuming organisms at a lower trophic level in the food chain (e.g. a primary consumer eating a producer or a secondary consumer eating a primary consumer)
