Science Unit 3

Name three examples of lipids

Fats, oils and waxes.

How much of your body is made up of water?

About two-thirds.

What is the difference between an element and a compound?

An element is a substance that, when combined with other elements, makes up a compound.

Elements

Any substance that cannot be broken down into simpler substances.

What are four types of molecules found in living things?

Carbohydrates, lipids, proteins and nucleic acids.

Four important organic compounds found in living things

Carbohydrates, lipids, proteins, and nucleic acids

Name two kids of Nucleic Acids

DNA and RNA

What is the role of enzymes in cells?

Enzymes in your saliva speed up the digestion of food by breaking down starches into sugars in your mouth.

Name some foods that are high in protein

Meat, eggs, fish, nuts, and beans.

How are organic and inorganic compounds different?

Organic compounds are living and contain carbon, while inorganic compounds are non-living and do not contain carbon.

RNA (rybonuleic acid)

Plays an important role in the production of proteins. RNA is found in the cytoplasm as well as in the nucleus.

Which of the four types of organic molecules contain the element nitrogen?

Proteins and nucleic acids.

What else do Proteins do?

Proteins form parts of cell membranes and make up many of the organelles within the cell.

Amino Acids

Smaller molecules that make up the larger Protein molecules. There are 20 amino acids. They create different types of proteins depending upon the way the they are linked together, how many and what kinds.

What is the difference between sugar and starch?

Sugars are produced during the food-making process that takes place in plants, while starches are where plant cells store excess energy. Foods that come from plants, such as potatoes, pasta and rice contain starch.

Nucleic Acids

Very long organic molecules made of carbon, oxygen, hydrogen, nitrogen, and phosphorus. They contain the instructions that cells need to carry out all the functions of life.

What three important functions does water perform in cells?

Water helps cells keep their size and shape. Water helps keep the temperature of cells from changing rapidly. Water molecules take part in many chemical reactions in cells.

What compound is needed for most chemical reactions to take place in cells?

Water.

Compound

When two or more elements combine chemically.

Enzyme

a type of protein that speeds up a chemical reaction in a living thing.

Carbohydrates

energy-rich organic compound made of the elements carbon, hydrogen, and oxygen. Examples are sugars and starches.

Lipids

energy-rich organic compounds made of carbon, hydrogen, and oxygen, but contain more energy than carbohydrates.

Proteins

large organic molecules made of carbon, hydrogen, oxygen, nitrogen and in some cases, sulfur.

DNA (deoxyribonucleic acid)

the genetic material that carries information about an organism and is passed from parent to offspring. The information in DNA also directs all of the cell's functions. Most of the DNA is found in the chromatin in the nucleus.

Molecule

the smallest unit of many compounds