Ch. 2,3,4 SG questions

What are the major groups of organic compounds studied in biology?

lipids, Carbohydrates, nucleic acid, and proteins

Define the following: a. isomers b. geometric isomers c. enantiomers d. Why are enantiomers of biological interest? e. What is the significance of functional groups?

a.Compounds that have the same numbers of atoms of the same elements but different structures causing them to have different properties b. They have the same covalent partnerships, but they differ in spatial arrangement. c. they are mirror images of each other, they can never be arranged to be in the same position. d.Enatomers are important in the pharmaceutical industry because the two enantiomers of a drug may not be equally effective; in some cases they can be harmful, causing defects. e. Functional groups effect chemical reactions in characteristic ways.

What is a hydrogen bond? How does it form and how is it different from a covalent bond?

A hydrogen bond is an attraction, It's formed when a hydrogen is covalently bonded to one electronegative atom. A hydrogen differs from a covalent bond because it's an attraction, not a real bond. It's an attraction because the positive charge of the hydrogen is attracted to a negative charge of another atom.

What happens when electrons change levels?

An electron can only move from shell to shell by releasing or absorbing energy. If the electron absorbs energy it moves to a shell farther from the nucleus ( light), if the election loses energy it moves to a shell closer to the nucleus (heat)

Main topics of natural selection Essay has to do with water- Properties

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Sketch a few molecules of water, indicate their polarity, and where H bonds form.

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Describe some of the shapes of carbon skeletons.

Length, Double bonds, Branching, and rings

How do non-polar covalent bonds differ from polar covalent bonds?

Non-polar covalent bonds are when the electrons are shared equally (EX: H2) Polar covalent bonds are when one atom is bonded to a more electronegative atom causing an unequal sharing of electrons.

Define organic chemistry.

Study of Carbon compounds

Helium has an atomic number of 2 and atomic mass of 4. Explain.

The atomic number is the number of protons in the elements nucleus and the mass tells us that helium has two protons and to neutrons in it's nucleus; its the sum

Why do atoms form covalent vs. ionic bonds?

Atoms form covalent bonds, a sharing of electrons between two nonmetals, to complete their outer shells. Atoms form ionic bonds, a transfer of electrons, which happens when one atom is more electronegative than the other, this is between a metal and nonmetal.

Define isotope and give some examples.

Atoms of the same element that differ in the number of neutrons. Carbon-12 has two isotopes, Carbon-13 an Carbon-14. They are the same element but they have different neutrons, 12 has 6, 13 has 7 and 14 has 8

List the "special" properties of water and give an example of why the property may be important to living things.

Cohesion & Adhesion: These properties are what hold water molecules together otherwise water would be like grains of sugar, and as living organisms water makes up most of our body mass and is needed to live. Good Solvent: Allows for the dissolving of foods with nutrients for an organisms body. Lower density as a solid: Allows fish to still live in the water when water freezes, otherwise all marine life would not be able to survive. High Specific heat: Allows marine life to live in a stable environment temperature wise, so their bodies are no constantly going from hot to cool, which could throw off their homeostasis causing death. Also waters high specific heat keeps the earths temperature stabilized as well. High Heat of vaporization: Allows for water to vaporize easily, water as a vapor is cannot be drank by organisms and without water they would die.

For each of the functional groups, complete the chart:

Hydroxyl: Def: A hydrogen atom is bonded to an oxygen atom, which is bonded to the carbon skeleton of the organic molecule Name Of Compound: Alcohols Example: Ethanol Functional Properties: Polar due to much time near electronegative oxygen atoms; Can form hydrogen bonds with water, helping dissolve other compounds Carbonyl: Def: A carbon atom joined with an oxygen atom by a double bond Name Of Compound: Ketones and Aldehydes Example: Acetone and Propanal Functional Properties: Can be structural isomers, found in sugar Carboxyl: Def: Oxygen atom is doubled bonded to a carbon atom that thats bonded to an - OH group Name Of Compound: Carboxylic Acid Example: Acetic acid Functional Properties: acidic properties covalent bond between oxygen and hydrogen is polar Amino: Def: a nitrogen atom boned to two hydrogen atoms and to the carbon skeleton Name Of Compound: Amines Example: Glycine- amino acid Functional Properties: acts as a base, picks u H+ from surrounding solution; ionized Sulfhydryl: Def: sulfur atom bonded to hydrogen; resembles a hydroxyl groups shape Name Of Compound: Thiols Example: Cysteine Functional Properties: Can form covalent bonds; helps stabilize proteins structure Phosphate: def: Phosphorus atom bonded to four oxygen atoms; one oxygen atom is bonded to the carbon skeleton, two carry negative charges Name Of Compound: Organic phosphates Example: glycerol phosphate Functional Properties: contributes negative charge to the molecule of which it's apart, can react with water, releasing energy Methyl: DEf: carbon atom bonded to three hydrogens atoms Name Of Compound: Methylated Compounds Example: 5- Methyl Cytidine Functional Properties: affects expression of genes, affects shape and functions depending on arrangement

What are the most common elements in the human?

Oxygen, Carbon, nitrogen, Hydrogen- Phosphorus, calcium, sulfur, potassium

Why is H bonding so important to water's properties?

Properties such as cohesion, adhesion, surface tension, and high specific heat would not exist without hydrogen bonding. The Hydrogen bonds are what hold the water molecules together.

How are isotopes used in biology?

Radioactive isotopes are used to date fossils and label chemical substances in metabolic processes;, treatment of disease (i.e. radiation therapy for cancer, radioactive iodine treatment for thyroid cancer) Imaging, diagnosing, test, treatment.

What is the significance of valence numbers?

This determines the behavior of the atom