biology chap. 3

Biological Macromolecule

Large molecules necessary for life, built from smaller organic molecules.

Four major classes of Biological Molecules

Carbohydrates

lipids

proteins

nucleic acids

Dehydration Synthesis

Process in which water is removed to join two monomers and form a covalent bond.

Hydrolysis

Reverse process of dehydration synthesis where water is added to break down polymers into monomers.

ratio of carbon to hydrogen atoms in carbohydrates

1:2 ratio

Monosaccharides

The monomers of carbs, simple sugars.

Disaccharides

Carbohydrates composed of two monosaccharides bonded together.

3 common disaccharides & monosaccharides

lactoseis: glucose and galactose

maltose: two glucose molecules

sucrose: glucose and fructose

Polysaccharide

Complex carbohydrates composed of many sugars.

Starch

Storage form of glucose in plants.

Glycogen

Storage form of glucose in humans.

Cellulose

Makes up the cell walls of plants and provides structural support to cells.

Chitin

Forms the outer skeleton of arthropods providing protection.

Lipids

Hydrophobic biomolecules insoluble in water containing carbon, hydrogen, oxygen, and sometimes phosphorus.

3 functions of lipids

Store energy

Insulate for heat regulation

Form cell membranes

5 types of lipids

Waxes

Steroids

Phospholipids

Glycerol

Triacylglycerol

2 Fat Molecule Components

Consists of glycerol and fatty acids.

another name given to fats and why

Triacylglycerols & because of their chemical structure

Saturated Fatty Acids

Fats that contain only single hydrogen bonds.

Unsaturated Fatty Acids

Fats that contain one or more double bonds in the hydrocarbon chain.

Monounsaturated Fat

Fatty acids with one double bond; example is olive oil.

Polyunsaturated Fat

Fatty acids with multiple double bonds; example is fish oil.

What is a Biological Macromolecule?

Large molecules necessary for life, built from smaller organic molecules.

difference between cis vs trans fat molecules

cis= A bend prevent the molecules from packing tightly, keeping them in a liquid stay at room temp

trans= artificially created molecules pack more tightly, making them solid at room temp

Why are trans fats not ideal for the human diet?

trans fats increase risk of heart disease & are considered unhealthy

Essential Fatty Acids

Fatty acids that must be obtained from the diet.

What are good sources of omega-3 fatty acids and why are they important?

fish

nuts

soybeans

they are important because the body cannot synthesize them & must obtain them from food

Waxes Function

Provides protective coatings in plants, such as on their leaves.

Phospholipids Structure

Contains fatty acid chains attached to glycerol, responsible for plasma membrane's dynamic nature.

Steroids Structure

Comprised of four fused hydrocarbons.

Cholesterol

The most common steroid in the body.

2 Types of Proteins & function

Digestive enzymes and hormones;functions are catabolizing nutrients into monomeric units and for hormones coordinate different structure, body system activities

Amino Acids

The monomers of proteins; there are 20 amino acids.

Peptide Bond

A bond formed between two amino acids by a dehydration reaction.

Polypeptide

A long chain of amino acids linked by peptide bonds.

4 levels of protein structure

Primary

Secondary

Tertiary

Quaternary

Denaturation

Loss of shape in a protein due to changes in temperature, pH, or chemical exposure.

2 Main Nucleic Acids

DNA and RNA, responsible for genetic information storage and protein synthesis.

Nucleotide Structure

Consists of a nitrogenous base, pentose sugar, and phosphate group.