Carbohydrates and Lipids Quiz

What is a carbon backbone or skeleton? What are three ways they can be arranged?

A carbon skeleton is the chain of carbon atoms that forms the "backbone," or foundation, of any organic molecule. They can be arranged in closed circles, straight lines , or branches.

Why is cholesterol such an important steroid?

Because it modulates the fluidity of cell membranes and is the principal constituent of the plaques implicated in atherosclerosis.

How does being hydrophobic relate to lipid function?

Being hydrophobic relates to lipid function because they both repel water. Lipids make up the cell membrane so they keep the cell together. Lipids regulate water flow in and out.

Are carbohydrates hydrophilic or hydrophobic? What are the functions of carbohydrates?

Carbohydrates are hydrophilic. Functions: short-term energy, intermediate-term energy storage, structural components, and provide fiber

2 functional groups (being quizzed on)

Carbohydrates: composed of carbon, oxygen, and hydrogen Lipids: insoluble to water; used by cells for energy storage, insulation, and protective coatings; ex: fats, oils, waxes, steroids

Compare and contrast dehydration and hydrolysis.

Dehydration rips water away from two molecules so it can combine the two molecules. Hydrolysis breaks down molecules by reacting with water.

Which sugar molecule is the main fuel for cellular work?

Glucose

How are monomers related to polymers?

Monomers make up polymers.

List examples of mono and disaccharides.

Monosaccharide examples are glucose and fructose . Disaccharide examples are lactose and sucrose.

What is the monomer or subunit for carbohydrates?

Monosaccharides

Compare and contrast saturated and unsaturated fats.

Saturated- single bonds; solid at room temperature; come from animals Unsaturated- double bonds; liquid at room temperature; come from plants

For each of the following polysaccharides describe their structure, tell where they are stored, and how they are used: starch, glycogen, and cellulose.

Starch is found in plant cells that consists entirely of glucose monomers. Inside a plant cell, such as a potato cell, starch chains branch and coil up like the loops of a telephone cord. Starch is used to serve as sugar stockpiles. Plant cells, like animal cells, need sugar for energy to perform work, and as raw material for building other molecules. Glycogen in the human body is primarily stored in the cells of the liver and the muscles, and functions as the secondary long-term energy storage. Glycogen plays an important role in the glucose cycle. It forms an energy reserve that can be quickly mobilized to meet a sudden need for glucose. Glycogen represents the main storage form of glucose in the body. Cellulose is found in plant cell walls and is the fiber.

What determines the properties of an organic molecule?

The functional groups.

What are 3 functions of lipids? Describe the structure of a fat.

Three functions of lipids are storing energy, forming cell membranes, and carrying messages. Fats are triglycerides which means their basic unit is a glycerol molecule which are attached to three fatty acids through bonds.

Describe the structure and function of triglycerides.

Triglycerides are the main lipids in the body. Made up of 3 glycerides and fatty acids.

Hydrolysis

a chemical process in which a molecule of water is split, resulting in the separation of a large molecule into two smaller molecules.

Dehydration Reaction

a chemical reaction that involves the loss of a water molecule from the reacting molecule.

Hydrocarbon

a compound of hydrogen and carbon, such as any of those that are the chief components of petroleum and natural gas

Functional group

a group of atoms responsible for the characteristic reactions of a particular compound

Isomer

compounds with the same simple formula but different 3-dimensional structures resulting in different physical and chemical properties.

Unsaturated fat

double bonds; liquid at room temperature; come from plants

Hydrophilic

having a tendency to mix with, dissolve in, or be wetted by water

Lipid

large organic compounds made mostly of carbon and hydrogen, with a small amount of oxygen; examples are fats, oils, waxes, and steroids; are insoluble in water and used by cells for energy storage, insulation, and protective coatings, such as in membranes

Steroid

lipid molecule with ring structure

How is steroid structure different from other lipids?

lipids: long chains of fatty acids; steroids: ring structure

Polymer

long chain of small molecular units (monomers)

Mono, di, polysaccharide (one, two, or many sugars)

long polymer chain made up of simple sugar monomers

Why are hydrocarbons important?

needed to supply energy for cars.

Fat

organic compound consisting of a three-carbon backbone (glycerol) attached to three fatty acids.

Carbohydrate

organic compound used by cells to store and release energy; composed of carbon, hydrogen, and oxygen

Cholesterol

regulates membrane fluidity and functions as a precursor molecule in various pathways

Hydrophobic

repelling water

Saturated fat

single bonds; solid at room temperature; come from animals

Monomer

small molecular unit that is the building block of a large molecule