CH 2 CYU questions

Why are steroids, like cholesterol, considered to be lipids?

Steroids are lipids because they are hydrophobic and insoluble in water

Differentiate between glycogen and starch.

Storage molecules in cells -Glycogen in animal cells -Starch in plant cells

List the three components of ATP. Why is ATP an important energy molecule for cells?

The three components of ATP are Adenine, Ribose, and three phosphate molecules

List the three components of nucleic acids. Identify the nucleotides found in DNA and RNA.

The three components of nucleic acids are Nitrogen base, Pentose (5-carbon) sugar,and Phosphate Nucleotides in DNA:adenine, thymine, cytosine, and guanine Nucleotides in RNA: adenine, uracil, cytosine, nd guanine

Explain the difference between a molecule and an atom.

Atoms are small, whereas molecules are larger and are formed when two or more atoms interact.

Differentiate between cellulose, chitin, peptidoglycan, and lipopolysaccharide.

Cellulose: Gives strength and rigidity to plants and microscopic algae Chtiin: Found in the exoskeletons of certain fungi Peptidoglycan: Provides the main source of structural support to the bacterial cell wall Lipopolysaccharide: Complex of lipid and polysaccharide found in the outer membrane of gram-negative bacteria•Responsible for symptoms of fever and shock

Differentiate between a proton, electron, and a neutron.

Protons have a positive charge and can be determined by atomic number. Electrons have a negative charge and determine the number of bonds. Neutrons have o charge.

-What role do functional groups often play in organic molecules? -Which functional group can act as an acid? -Which functional group can act as a base? -Which functional group can assist in energy transfer reactions? -Which functional group is common to alcohols? -Which two functional groups are common to amino acids?

- Functional groups Help define the class of certain groups of organic compounds - carboxyl & phosphate -amino - phosphate -hydroxyl - sulfhydryl and

Why is carbon considered the fundamental element of life?

-Ideal atomic building block to form the backbone of organic molecules -Four electrons in outer orbital can be shared with for other atoms, including carbon

What do scientists mean when they say that a protein has "denatured"? Why is this an issue for a protein?

A protein is denatured when there is a disruption of the native state of a protein, once denatured it loses the ability to be effective.

Differentiate between a solute and a solvent.

A solute is a substance that gets uniformly dispersed into a solvent. The solvent is the dissolving medium

Differentiate between acids and bases chemically, and in terms of their position on the pH scale.

Acidic solution: occurs when a component dissolved in water releases excess hydrogen ions (H+)-Also absorbs excess hydroxyl ions (OH-) Basic solution: occurs when a component dissolved in water absorbs excess hydrogen ions (H+)-Also releases excess hydroxyl ions (OH-) Lower on the scale = acidic Higher on scale = basic Neutral = 7

What is agar and why is it useful in the microbiology lab?

Agar is a Natural component of seaweed and it is Important in preparing solid culture media

List and describe four types of chemical bonds.

Ionic: when two atoms interact by exchanging/transferring electrons Covalent: atoms will share electrons Hydrogen: weak or temporary interactions that exist only between ionic and polar molecules Van Der Waals: The weakest of the chemical bonds

Provide a brief definition of pH.

Measures the acid and base concentrations of solutions

Differentiate between a monosaccharide, a disaccharide, and a polysaccharide.

Mono = 1 sugar Di = 2 sugars Poly = 3 or more sugars

How do phospholipids differ from true lipids? Why are phospholipids important biological molecules?

Phospholipids Have a hydrophilic region and a hydrophobic region whereas lipids are hydrophobic

Differentiate among primary, secondary, tertiary, and quaternary levels of protein structure.

Primary (1o) structure:-The type, number, and order of amino acids Secondary (2o) structure:-Arises when functional groups on the outer surface of the molecule interact with each other.•α helix•β pleated sheet Tertiary (3o) structure:-Torsion caused by interaction between functional groups Quaternary (4o) structure:-Large multiunit proteins formed by more than one polyprotein

Differentiate between saturated and unsaturated lipids

Saturated fatty acid: All carbons in the fatty acid chain are single-bonded to 2 other carbons and 2 hydrogen atoms Unsaturated fatty acid: a fatty acid in which at least one double bond exists between carbon atoms

What role does water often play in the creation of solutions?

Water is the most common universal solvent.

What is an atom?

smallest unit of matter