Bonding Basics

Atoms like to bond with other

atoms

•What does that make?

• Molecules and compounds!

•Why is that important?

Examples of common

compounds: H2O, NaCl,

C6H12O6

•What is a bond?

Bonds?

Major kinds of bonds

• Covalent

• Ionic

•Hydrogen

Covalent Bonds

• A bond where atoms share

electrons

Ionic Bonds

• A bond where one

atom takes an electron

from another atom

• They bond because

they are attracted to

each other

• Opposites attract

• + and -

So what does all this have to

do with biology

• Bonding makes molecules

•Molecules make up cells and allow cells to

work

• Cells are the functional unit of life

Lets talk molecules examples

•What is a molecule again?

• Some common examples?

Macromolecules

• Some molecules are very big

• Made of lots of atoms!

Macromolecules

The 4 macromolecules of life

• Carbohydrates

• Proteins

• Lipids

•Nucleic Acids

What do you know?

Macromolecules are made of monomers

• Monomer- single unit

• Polymer- a chain of many single units

Carbohydrates

•Monomer:

Monosaccharide

• EX: Glucose

Carbohydrates

•Monosaccharides can

be linked together to

form disaccharides or

polysaccharides

• EX: Sucrose

Carbohydrates

• Polysaccharides

• Starch

• Glycogen

What are carbohydrates good

for?

• Energy storage!

What are carbohydrates good

for?

•Also used to build structure

• Plants, animals and fungi

Foods that have carbohydrates

Protein

• Monomer: Amino Acid

Protein

• Amino acids can be linked together to form proteins

• Long chains that fold to form 3-dimensional shapes

Protein

• Some proteins are made of multiple

chains connected together

What do proteins do?

• Used to build tissues and organs

• Muscles, skin, hair

• Used in chemical reactions of the cell and body

• Control cell growth, transport oxygen in the blood,

communicate from cell to cell, immune system,

Enzymes

Computer Survey

• Common sources of

carbohydrates

• Which is the best source?

• Common sources of protein

• Which is the best source?

Nucleic Acids

•What are they?

• EX: DNA and RNA

Nucleic Acids

•What do they do?

• Store information in cells

• In a code!

• Tells your cells how to function

• Used to transmit information from parents to offspring

Nucleic Acids

•Monomer: Nucleotide

Nucleic Acids

• There are 4

types of

nucleotides

found in DNA

Nucleic Acids

•Nucleotides link to form a long chain

•DNA is made of 2 long chains bonded together

Nucleic Acids

• The sequence of the nucleotides creates the code

Lipids

•What are they?

• Fats and oils

• Non-polar: they won’t dissolve in water

Common Lipids

Lipids• Do we need lipids?

• YES!

• Used for long term energy storage, insulation, hormones and protective coatings

• Lipids hold more energy than carbohydrates!

Lipids

• Lipids are an essential part of cell membranes

Lipids

• Just like everything else, too much of a good thing is a bad thing

Lipids• Monomer: no true monomer\

• Polymers are made from glycerol with fatty acid tails

Partner activity

•What are the similarities between the 4

molecules?

•What are the differences?