These are a group of animals that can stay both on land and in water.

These are a group of animals that have lungs to breathe, and dry, scaly skins in some areas or all over their bodies.

These are animals that lay eggs outside.

They are classified after the female's mammary glands because they are the only animals that produce milk.

These are gnawing animals. They have huge incisor teeth to gnaw food and wood, as well was bite their predators.

These are "pouched" animals that give birth to their young.

The highest order of mammals is the _____________. Because they have well-developed brains and body parts.

These are egg-laying mammals.

These are also known as roundworms and are generally considered parasitic organisms.

These are arthropods with four pairs of legs.

It is the study of the interactions among organisms and their environment.

It is a type of relationship wherein two organisms benefit from each other.

It is a type of relationship wherein one organism benefits, but the other organism is unaffected.

This type of reef is commonly found near the coastline or in places where the water is shallow.

This is a small, isolated reef that usually occurs between fringing reefs and barrier reefs.

It is a force that pulls or attracts all objects toward each other.

Life would be possible even without gravity.

It refers to the amount of matter present in an object. It is usually measured in grams (g) or kilograms(kg).

The person's _________ is affected by the pull of gravity.

It is the measure of the force of gravity on an object.

It determines the amount of material in an object.

These are two equal forces acting on an object in opposite directions.

Weight is a force too.

Forces that result from physical interaction are called _____________________.

It is a push or pull on an object.

It is a special kind of force that acts in the opposite direction as the applied force.

It happens when the surface of two objects that are at rest are in contact with each other.

It is a friction that acts between a moving object and the surface where it is moved.

It is a type of friction that happens when two solid surfaces slide over each other.

This type of friction acts on objects that are moving through a fluid such as liquid or gas.