Biology Chapter 3 Molecules of Life

Biological/Organic Molecules

Large molecules that are essential for life.

Macromolecules

Molecules that are large in size and are made up by combining smaller units together.

Molecule

A substance that is made up of two or more atoms bound together.

Carbohydrates

Large molecules that contain the elements carbon, oxygen, and hydrogen. The primary fuel for our bodies.

Monosaccharides

The simplest form of carbohydrates and they are simple sugars.

Glucose

Has 3 fates in your body once you eat and digest: provides immediate energy, can be stored short term as glycogen, or can be stored long term and converted to fat.

Complex Carbohydrates

Carbohydrates that are made up of two or more sugar molecules.

Disaccharides

Contain two different sugar molecules, more complex than a monosaccharide but still not very complex.

Sucrose

A common disaccharide made up of a glucose and a fructose molecule.

Lactose

Another common disaccharide, the sugar found in milk.

Polysaccharides

Contain thousands of sugar molecules that are linked together with a glycosidic bond.

Glycosidic Bond

A special type of covalent bond that forms between sugar molecules.

Starch

Found in plants and is used as fuel storage for plants.

Cellulose

The structural component of plants (fiber, we can't digest it).

Glycogen

Found in the liver and muscle of humans.

Short Term Energy

Eating simple carbohydrates will provide you a short burst of energy but it wears off quickly.

Long Term Energy

A diet of complex carbs provides a sustained release of energy for a longer period of time.

Lipids

Come in several forms and include triglycerides, sterols, and phospholipids.

Triglycerides

Dietary fats that serve different functions in the body and are composed of a head region and a tail region that are linked together.

Sterols

A group of lipids that help with regulating growth and development with a basic structure of 4 carbon rings.

Phospholipids

The main component of our cell membranes and the cell membranes of all living organisms that have similar structure as triglycerides.

Glycerol Molecule

A small molecule that is made up of 3 carbons bound to 3 oxygen and 5 hydrogen.

Fatty Acids

The tail region of triglycerides that are hydrophobic and are made up of 3 tails linked to the glycerol head.

Functions of Triglycerides

store lots of energy for long term storage, insulation for organisms, cushioning between organs and tissues and bones and skin.

Types of Triglycerides

Naturally occur in two different forms: fats and oils.

Fats

Derived primarily from animal sources, solid at room temperature, composed of saturated fatty acids.

Oils

Derived primarily from plant sources, liquid at room temperature, composed of unsaturated fatty acids.

Saturated Fatty Acids

In the fatty acid tails of a fat, each carbon is bound to at least 2 hydrogen atoms, making them straight and solid at room temperature.

Unsaturated Fatty Acids

Fatty acid tails have at least one carbon bound to only one hydrogen, allowing for double bonds that create kinks, making them liquid at room temperature.

Trans-Fats

Human made fats manufactured to increase shelf life and improve texture of foods; linked to increased risk of high cholesterol and heart disease.

Hydrogenated Oil

Created through the hydrogenation process which bombards unsaturated fat with hydrogen atoms, creating trans-fats.

Cholesterol

A type of lipid that is an important component of most cell membranes that helps maintain fluidity during temperature changes; produced by liver cells.

Steroid Hormones

Compounds derived from cholesterol that regulate growth, sexual development, maturation, and sex cell development.

Anabolic Steroids

Often abused by athletes to increase muscle mass.

Fatty Acid Tails

The structural components of triglycerides that determine whether they are saturated or unsaturated and are hydrophobic.

Saturated

Refers to fatty acids where carbon is fully bonded, resulting in straight tails.

Unsaturated

Refers to fatty acids with double bonds, resulting in kinks in the tails.

High Cholesterol

A condition that can be exacerbated by a diet high in trans fats.

Heart Disease

A health condition linked to high levels of cholesterol and trans fats in a person's diet.

Cell Membrane

A double layer of phospholipids, where the tails interact with each other forming the middle area and the heads facing inward and outward toward the fluid.

Side Chains

The ____ ______ in sterols determine the type of sterol based on their modifications off the basic structure of four interlinked rings.

Proteins

The major building blocks of organisms, used as structural components, integral in producing hair, feathers, tendons, ligaments, and cartilage, and essential for muscle contraction.

Protein Hemoglobin

Responsible for the transport of oxygen around our bodies.

Amino Acids

The building blocks of proteins, linked together by peptide bonds to form proteins.

Peptide Bond

A special covalent bond that links amino acids together in a protein.

Polypeptide

Another name for a protein, consisting of many peptide bonds.

Essential Amino Acids

Amino acids that must be obtained from our diet; 10 out of the 20 amino acids are essential.

Complete Proteins

Foods that contain all the essential amino acids.

Primary Structure

The initial structural form of a protein, comprised of amino acids in a linking chain.

Secondary Structure

Occurs when parts of the amino acids in a protein chain interact, causing the protein to fold into zig-zag or spiral shapes.

Tertiary Structure

The three-dimensional shape of a protein formed by further folding due to interactions of the side chains of the amino acids.

Quaternary Structure

The result of the interaction between different protein chains or multiple polypeptides, forming a functional protein.

Hemoglobin (as a quaternary structure)

An example of a quaternary structure protein that has 4 subunits (4 different protein chains) bound together.

Protein Structure Influences Function

Proteins can appear in 4 different structural forms, only two of which comprise a functional protein.

Environmental Sensitivity of Proteins

Proteins are highly sensitive to environmental conditions, with different proteins having different optimal operating environments.

Hydrophobic

Referring to the property of being water-repelling; characteristic of the fatty acid tails in phospholipids.

Hydrophilic

Referring to the property of being water-attracting; characteristic of the glycerol head in phospholipids.

Immune System Role of Proteins

Proteins protect our bodies from foreign invaders and play a large part in our immune system.

Clotting Proteins

Specialized proteins that help clot our blood when we get injured.

Transport Function of Proteins

Proteins help transport essential elements in our bodies and cells.

Optimal Operating Environments

Different proteins have different optimal operating environments.

Enzyme Proteins

Proteins in your stomach help break down food.

pH Sensitivity of Proteins

Proteins are sensitive to changes in pH and temperature.

Denaturation

When a protein's structure is being altered and the folding that created the functional 3D shape is changed to make the protein dysfunctional.

Enzymes

Proteins that help speed up biological, chemical reactions and act as a catalyst to speed up the reaction rates.

Activation Energy

The energy needed for the chemical reaction to occur without an enzyme.

Lock and Key Configuration

Enzymes have a ____ ___ ___ _____________ in which each enzyme is specific for certain chemicals.

Active Site

The area where the chemical with the correct shape fits into the enzyme.

Substrate

The chemical that fits into the enzyme and is the subject of the reaction.

Enzymatic Reaction Products

The result of the enzymatic reaction produces two products.

Reusability of Enzymes

Once the reaction is finished, the enzyme is ready to perform another reaction.

Nucleic Acids

Macromolecules whose function is to store information that is passed around the body about making the body and the regulation of cellular activity.

Nucleotides

The building blocks of nucleic acids composed of a sugar molecule (5 carbon sugar), phosphate group (slight negative charge), and a nitrogenous base (bases used depend on the nucleic acid in question).

Deoxyribonucleic Acid (DNA)

A type of nucleic acid that stores genetic information.

Ribonucleic Acid (RNA)

A type of nucleic acid that helps decipher the info stored in DNA.

Structure of DNA

DNA is double stranded and spirals on itself to form a helical structure.

Function of DNA

The storage of genetic information necessary to direct the production of proteins.

Nitrogenous Bases in DNA

Adenine (A), Guanine (G), Cytosine (C), and Thymine (T) and their sequence determines the message and info being stored.

RNA Structure

Single stranded, made up of a Ribose sugar, and has a Uracil nitrogenous base

Role of RNA

RNA acts as the middleman molecule that takes instructions for protein production from DNA.

Phosphate Sugar Backbone

Forms the outside structure of the helical structure of DNA.

Fidelity of Information

The stored info in nucleic acids is available to be passed on to other cells and offspring where the fidelity of the info is maintained.

Characteristics of Lipids

Nonpolar, have a lot more energy than a carbohydrate, hydrophobic.