BASIC IDEAS OF BIOLOGYBASIC IDEAS OF BIOLOGY

The Molecules of CellsThe Molecules of Cells

By Mary Anne McMurrayBy Mary Anne McMurrayHenderson Community CollegeHenderson Community College

The large, complex molecules The large, complex molecules of living things are of living things are organicorganic moleculesmolecules..

Name the four major groups of organic molecules found in living things.

The large, complex molecules The large, complex molecules that form living things include:that form living things include:

Carbohydrates Lipids Proteins Nucleic acids

List several ways that organic List several ways that organic molecules are important to molecules are important to life processes.life processes.

Organic molecules are Organic molecules are important to life processes important to life processes because:because:

They store energy. They form cell membranes. They provide structural support. They help control chemical reactions in

organisms. They store hereditary information.

What elements are most What elements are most common in the organic common in the organic molecules found in molecules found in living things?living things?

All All organicorganic moleculesmolecules contain contain carboncarbon..

They also contain other atoms, such as hydrogen nitrogen oxygen sulfur phosphorus

CCHH

OO

SS

NN

PP

The atoms in organic The atoms in organic molecules are bonded molecules are bonded together by_________ bonds.together by_________ bonds.

Give examples of some simple organic molecules and show how they are bonded together.

The atoms in organic The atoms in organic molecules are bonded molecules are bonded together by together by covalent bondscovalent bonds..

H

H C H

H

C HH C

O

H H

HH

H C O H

H

H

What are the primary What are the primary functions of carbohydrates functions of carbohydrates in living things?in living things?

Examples of carbohydrates Examples of carbohydrates are ___________, such as are ___________, such as _________ and _________ _________ and _________ and ____________.and ____________.

Carbohydrates -- Important fuel Carbohydrates -- Important fuel molecules and structural molecules and structural components of cells.components of cells.

C6H12O6

C12H22O11

Sugars, such as

glucosesucrose

Starches are more complex carbohydrates

Give examples of lipid Give examples of lipid molecules and tell how they molecules and tell how they are used by living things.are used by living things.

Lipids includeLipids include

Fats (triglycerides) are important energy storage molecules,

Phospholipids, which make up the framework of cell membranes,

Steroids, including some important hormones

What characteristic is What characteristic is common to all lipid common to all lipid molecules?molecules?

Lipid molecules are all Lipid molecules are all hydrophobichydrophobic..

H2OH2O

H2OH2O

Give examples of proteins that Give examples of proteins that are important to the are important to the structurestructure of organisms.of organisms.

Some proteins are important Some proteins are important to the structure of organismsto the structure of organisms

our hair spider silk fibers of tendons and ligaments

Name some proteins that Name some proteins that serve these specific functions.serve these specific functions.

carrying oxygen-- _______________________________

defense against microscopic invaders-- _______________________________

some hormones, such as _______________________________

Other proteins are important Other proteins are important in such jobs asin such jobs as

carrying oxygen-- HEMOGLOBIN

defense against microscopic invaders-- ANTIBODIES

some hormones, such as ADRENALIN

How do some proteins How do some proteins function as enzymes?function as enzymes?

Some V.I.P.’s (Very Important Some V.I.P.’s (Very Important Proteins) are enzymes.Proteins) are enzymes.

REACTANTS --->chemical process-->PRODUCTS

+Some reactions are catalyzed by enzymes.

What are the steps in enzyme What are the steps in enzyme function?function?

An enzyme can speed up a An enzyme can speed up a chemical reaction.chemical reaction.

+

An enzyme has a shape that the substrate can fit.

An enzyme substrate complex forms.

The products are formed.

The enzyme is ready to catalyze another reaction.

What smaller subunit are What smaller subunit are proteins made of?proteins made of?

Proteins are made of Proteins are made of amino amino acidsacids..

20 different amino acids make up all our proteins

An amino acid has a Central carbon atom,An amino group

A carboxyl group

andAn R-group

The R-group varies from one amino acid to another

A hydrogen atom

How are amino acids How are amino acids combined to form proteins?combined to form proteins?

What makes one protein What makes one protein different from another?different from another?

Amino acids can be put Amino acids can be put together to make proteins.together to make proteins.

Amino acids are arranged linearly to form the protein’s primary structure.

Covalent bonds, called peptides, link the amino acids.

What determines the specific What determines the specific shape of a protein?shape of a protein?

Why is the shape of a protein Why is the shape of a protein so important?so important?

Special bonds can link Special bonds can link nonadjacent amino acids to nonadjacent amino acids to help form the specific shape of help form the specific shape of a protein.a protein.

A protein’s shape determines its function.

Why are nucleic acids Why are nucleic acids important to living things?important to living things?

Name two kinds of nucleic acids. Name two kinds of nucleic acids.

Nucleic acids are the Nucleic acids are the blueprints for proteins.blueprints for proteins.

DNA (deoxyribonucleic acid) RNA (ribonucleic)

Much more to come about these very important biomolecules!

REVIEWREVIEW

What element is in all biomolecules? What kind of chemical bonds hold atoms

together in organic molecules? To what group of biomolecules does sucrose

belong? To what group of biomolecules do the

hormones testosterone and estrogen belong? What is one characteristic of all lipids?

Can you answer these Can you answer these questions?questions?

Which of these substances contains nitrogen? glycogen hemoglobin adrenalin cellulose

Which biomolecule forms the framework of cell membranes?

Which biomolecule contains peptide bonds?

Here are some important Here are some important questions about proteins.questions about proteins.

What is meant by the primary structure of proteins?

Why is the shape of a protein so important? What is the function of enzymes? What makes one amino acid different from

another? What makes one protein different from

another?

Can you answer these Can you answer these important “everyday” important “everyday” questions?questions?

What is the difference between saturated fats and unsaturated fats?

To what group of macromolecules does cholesterol belong?

Some fatty acids and some amino acids are said to be essential for humans; why are they called essential?