Variety Of Life: Science Review Lessons 6 - 12

2010

Discuss the following terms with your partner

• Warm blooded • Cold blooded • Micro organism• Invertebrate • Vertebrate • Trait • Fossil

• Paleontologist • Artificial selection • Radioactive dating • Natural selection • Kingdom • Species • Extinction • Endangered species

Identify the following terms

• Warm blooded: refers to animals that keep their body temperature at a roughly constant level. This involves the ability to cool down or produce more body heat.

Identify the following terms

• Cold-blooded: refers to animals that do not use their metabolism to maintain body temperature. They control their body temperature through external means, such as by basking in the sun or by hibernating.

Identify the following terms

• Micro organism: An organism that is so small that you need a magnifier such as a microscope to see it.

• Invertebrate: Any animal that does not have a backbone.

• Vertebrate: Any animal that has a backbone.

Identify the following terms

• Trait: a characteristic of a living thing that it inherits from its parents.

• Fossil: remains or traces of organisms from the past.

• Paleontologist: A scientist who studies fossils and other evidence of ancient organisms.

Identify the following terms

• Artificial selection: the breeding of organisms with desirable traits so that future generations will have the same traits.

• Radioactive dating: measurement of age by the amount of change in a radioactive substance.

Identify the following terms

• Natural Selection: A natural process in which the individual members of a species that are best adapted for an environment will be the members that are most likely to survive and reproduce.

• Kingdom: The largest grouping used to classify organisms.

Identify the following terms• Species: A group of living things that can breed

together and produce offspring that also can breed together.

• Extinction: the dying off of all the members of a species.

• Endangered species: a population of organisms which is at risk of becoming extinct.

Discuss with your partner:

Reasons why animals are becoming extinct.

Reasons why animals are becoming extinct.

1. Change in climate. 2. People have destroyed their environment. 3. People overhunt for food or kill animals for

sport.

Discuss with your partner:

How do we protect against unwanted micro organisms?

How do we protect against unwanted micro organisms?

• We use products to help preserve food from the action of micro-organisms.

• We use products to clean (soaps, hand sanitizers etc) to prevent micro organisms form harming us.

• We use medications to help prevent the spread of serious diseases that affect large areas like towns and cities.

Discuss with your partner:

Explain how micro organism can be both harmful and helpful.

Explain how micro organism can be both harmful and helpful.

Helpful Harmful

We use the food-eating habits of certain micro-organisms to make products that we like to eat.

For example:

-yeast helps us make bread-some species of bacteria help us make cheese.

Sometimes micro-organisms choose foods that we would rather they didn’t.

For example: -micro-organism can spoil the foods you like. -they can make the food dangerous to eat. -they release poisonous chemicals into the food as they eat it. -the poisonous chemicals can make us sick. (tonsillitis, pneumonia, ringworm, malaria etc) -In some cases, they can cause death.

Discuss with your partner:

How can scientists infer the age of fossils?

How can scientists infer the age of fossils?

1. Scientist use a technique called radioactive dating. All organisms contain a substance called carbon. Over time, it breaks down, releasing radiation in the process. Scientists call it carbon-14. Scientists can use carbon-14 to date fossils by measuring how much carbon-14 the fossils still contain.

How can scientists infer the age of fossils?

2. Scientists drill hot, hollow pipes into deep layers of ice. They then count the thin layers to see how many years the ice has been piling up.

Discuss with your partner:

Name the groups of vertebrates.

Name the groups of vertebrates.

1. Fish 2. Amphibians 3. Reptiles 4. Birds 5. Mammals

Discuss with your partner:

Give characteristics of specific vertebrates.

Give characteristics of specific vertebrates.

Amphibians Fish Reptiles Birds Mammals

Cold blooded Cold blooded Cold blooded Warm blooded Warm blooded

Bony skeleton Bony skeleton Bony skeleton Hollow-boned skeleton

Bony skeleton

4 limbs with webbed feet

All are aquatic Terrestrial, but spend time in the water

Terrestrial Mainly terrestrial; aquatic species need to breathe air

Smooth, moist skin

Skin covered with scales in most species

Scale-covered skin

Feather-covered skin; legs have scales

Skin covered with varying amounts of hair