Life Science Review

Other Life Cycles

(water cycle is covered in Earth science)

cycle
recurring series of events that happens in nature


 carbon dioxide - oxygen cycle
the process by which carbon dioxide and oxygen cycle among plants, animals, and the environment
Ecosystems
What is the difference between a population, community and ecosystem?
Organisms find these needs in their habitat

1. Food
2. Water
3. Space
4. A place to reproduce

  Description Example
One type of organism living in the
Population A herd of deer
same habitat
More than one type of organism Deer, trees, insects, bacteria,
Community
living in the same habitat mushrooms, wolves , flowers

Deer, trees, insects, bacteria,

The living and nonliving things in a
Ecosystem mushrooms, wolves , flowers, sun, lake,
habitat
soil, rocks, rain, snow, heat
 ecosystem
all living and nonliving things that interact with each other in an environment

Classify
to sort into groups by characteristic or property

What are the roles of producer, consumer, and decomposer?

Every organism (living thing) also has a niche (role) in its habitat. A niche is an organisms job or
what the organism does in the habitat. No two organisms have the same niche.

organism
any living thing

Some niche's include

Predator: An animal that eats another animal.

Prey: The animal that gets eaten

Producer: An orgainsm that gets its energy from the sun, such as a plant.
 producer
an organism that makes its own food using energy from the sun through a process called photosynthesis. Examples include flowers,
trees, and plants

Consumer: An animal that eats another animal for energy and nutrients, they are at 3 levels.

consumer
Primary Consumer: An animal that eats a producer (plant).
Secondary Consumer: An animal that eats a primary consumer.

Tertiary Consumer: An animal that eats a secondary consumer.

Decomposer: An organism that gets its energy and nutrients from dead organisms and turns them
into soil, such as fungi and bacteria.

decomposer
an organism that breaks down dead plants and animals. This allows nutrients to go back into the soil to be reused.
 How does energy move through a food web?

All the food chains in a habitat are put together in a food web to show how the food chains overlap.
Energy starts with the sun, then goes to plants and then consumers.
 What is the relationship between a good chain and a food web?

The energy pyramid tell us two things about how energy moves in an ecosystem:
1. In an ecosystem the producers have the most energy and the amount of energy goes down as you move
up the pyramid, the tertiary consumers have the least amount of energy in an ecosystem.

2. The producers in an ecosystem have the largest population and the size of the population goes down as
you move up the pyramid, the tertiary consumers have the smallest population in an ecosystem.
What is the relationship between Predator and Prey?
A predator is an animal that eats another animal. The animal getting eaten is the prey.

The graph above shows that as the population of the predator (fox) gets too high then the prey
population (rabbit) goes down. When the prey population goes down then the predator doesn't
have enough food and the prey population goes down. Because there are less predators then the
prey population goes back up. This goes on and on and on....

Adaptations
All organisms have adaptations that help them survive and thrive. Some adaptations are structural.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other
adaptations are behavioral. Behavioral adaptations are the things organisms do to survive .
Inherited Trait

Factors that are obtained from the parent generation.

Learned Characteristics

Things about you that you did not inherit from your parents but instead learned how to do

Influence

Things all around you that cause you to want to do a particular thing.

Types of Traits
Inherit Traits Learned Traits
Passed from parent to child (ex. eye color) Something that comes from practice & experience
The shape of a birds beak Riding a bike
spines on a cactus Animals obeying on command

Physical Adaptations
 Mimicry
 Hibernation
 Migration
 Camouflage
 Defense
 Prickly spines
 Body Covering – (ex. color, gills, scales…)
  Claws

Metamorphosis
Insects go through a life cycle of changes, called metamorphosis.
Metamorphosis is the physical change that an organism goes through as it grows and develops into an adult.

Two Kinds of Metamorphosis

1. complete metamorphosis

• Complete metamorphosis is a life cycle where the physical changes are completed in 4 distinct
stages:

• Egg

• Larva

• Pupa

• Adult
Butterflies exhibit complete metamorphosis.
2. incomplete metamorphosis

Incomplete metamorphosis is a life cycle where the physical changes take place in 3 stages –

1. Egg

2. Nymph

3. Adult
Grasshoppers and Frogs exhibit incomplete metamorphosis.