P3 Life Cycle of Animals (Concept Map)
Primary 3 Science — Concept Map
Created by Miss Clarissa Ng · www.clartutors.com
Different animals, different life cycles
How many stages, what the young look like, and where the cycle happens
Compare life cycles using HAS — Habitat, Appearance, Stages!
Some animals have three stages (egg → nymph → adult); others have four (egg → larva → pupa → adult).
Animals whose young do not resemble the adult have four stages — except the frog.
The nymph moults and grows; the larva feeds the most, and the pupa changes into the adult.
A life cycle happens entirely on land (chicken) or partly in water (frog, mosquito).
The mosquito is easiest to control at the egg, larval and pupal stages, when it cannot fly away.
How many stages
Three stagesegg → nymph → adult, eg. grasshopper, cockroach · egg → young → adult, eg. chicken
Four stagesegg → larva → pupa → adult, eg. butterfly, mealworm beetle, mosquito
It differsthe time an animal takes to develop into an adult varies from one animal to another
Does the young look like it?
Resembles the adultthe young of some animals look like the adult, eg. grasshopper
Does not resembleother animals have young that do not look like the adult, eg. butterfly
The rule to rememberall animals with four-staged life cycles have young that do not resemble the adult
Insects with three stages
Nymphthe young of an insect with a three-staged life cycle is called a nymph
Moultingthe nymph moults — it sheds its hard outer covering in order to grow bigger
Wings and reproductiona nymph has no wings and cannot reproduce, but the adult can fly and reproduce
Insects with four stages
Larvathe larva feeds the most as it grows, and it moults during this stage
Pupain the pupal stage the animal does not feed or move
Examplesthe butterfly, mealworm beetle and mosquito have four-staged life cycles
Where the cycle happens
Entirely on landsome animals spend their life cycle entirely on land, eg. chicken
Partly in waterothers spend their life cycle partly in water, eg. frog, mosquito
Why it matterswhere the cycle happens is one way to compare two animals
Mosquito control
Remove the waterthe female mosquito lays her eggs in stagnant water, so clearing it removes the eggs
Easiest stagemosquitoes are easiest to kill as eggs, larvae or pupae; oil on the water blocks the larva's breathing tubes
Hardest stagethe adult is hardest to kill because it can fly