MRS GREN

Key Stage 2

MRS GREN is a memory tool to help remember what makes something alive.

If something is Alive is must be able to:


Move - A uses its legs and wings to move in search of food. Respire - A fly gets energy from the food they eat. Sense - A fly can see with its eyes and taste with its feet. Grow - A fly begins its life in an egg and grows into a maggot before becoming a fly. Reproduce - Flies can mate to make new flies. Excrete - A fly breaths out waste gas and leave droppings of waste material. Nutrition - Flies must take in new material by eating food.	Move - The leaves of an oak tree will move to aim toward The Sun. Respire - Trees make their own food and send it around the tree to be used for energy. Sense - Oak trees sense the change in temperature and amount of light and lose their leaves in winter. Grow - Oak trees begin as a small seed and grow up to 20 metres tall. Reproduce - Oak trees make seeds called acorns which can grow into new oak trees. Excrete - Oak trees let out waste gases. Nutrition - Oak trees take in minerals and water the soil.

MRS GREN is an acronym used to help remember the criteria for something to be considered alive.

MRS GREN is a mnemonic, which is a tool to help remember something.

MRS GREN stands for:

Movement - All living creatures can change direction when moving.
Respiration - All living creatures can get energy from food.
Sensitivity - All living creatures can respond to changes in the environment.
Growth - All living creatures can get bigger by taking on new material.
Reproduction - All living creatures can make copies of themselves.
Excretion - All living creatures can get rid of waste materials.
Nutrition - All living creatures can take on new materials for movement, growth and repair.


The picture shows a micro-organism called a Euglena. Movement - The Euglena has a tail called a flagellum which it can use to swim. Respiration - The Euglena makes its own food and uses that food for energy. Sensitivity - The Euglena can sense light using an organelle called an eye spot. Growth - The Euglena gets bigger before dividing. Reproduction - The Euglena divides to make two identical copies of itself. Excretion - The Euglena gets rid of waste with a contractile vacuole. Nutrition - The Euglena takes in nutrients from the water around it.	This picture shows many muscle cells. Movement - Muscle cells can get longer and shorter. Respiration - Muscle cells get energy from the glucose in food. Sensitivity - Muscle cells respond to electrical signals to change length. Growth - Muscle cells get bigger before dividing. Reproduction - Muscle cells divide to make two identical copies of themselves. Excretion - Muscle cells pass waste materials into the blood to be taken away. Nutrition -Muscle cells get nutrients form the blood.