Electronegativity, Bond Types, Water Properties, and Organic Isomers in Biology

what are the primary ions in electrolytes

sodium, potassium, calcium, magnesium, and chloride

Electronegativity

the pull an atom has on its electrons

How does electronegativity effect the sharing of electrons between 2 atoms: Higher electronegativity means?

stronger pull on electrons

How does electronegativity effect the sharing of electrons between 2 atoms: bigger difference in electronegtivity?

more unequal sharing between electrons

How does electronegativity "sets the stage" for hydrogen bonding between water molecules?

Electronegativity makes water polar. Oxygen pulls electrons closer, making O slightly negative and H slightly positive. The H of one water molecule is attracted to the O of another, forming a hydrogen bond.

Non-polar Covalent Bond

two atoms have the same or similar

electronegativity they will share the electrons equally

Polar Covalent Bond

big difference in electronegativity between the two atoms, one will have a much stronger pull on those shared

electrons and they will share unequally

Hydrogen Bond Defintion

intermolecular bond (between molecules)

Why do hydrogen bonds occur?

because a slightly positive hydrogen is attracted to a slightly negative atom nearby, like oxygen.

What is the role of electronegativity in hydrogen bonding between water molecules?

Electronegativity makes water polar. Oxygen is slightly negative and hydrogen is slightly positive, so they attract and form hydrogen bonds.

Properties of Water (8)?

-water has a high specific heat

-water has a high heat of vaporization

-cohesion

-adhesion

-solid water is less dense than liquid water

-water is an excellent solvent

-water organizes non-polar regions of molecules

-water dissociates into ions

Water has a high specific heat:

define:

example of why/how this property is significant in LIVING organisms

-needs a lot of energy to chage temperatures

-significant because it helps keep the weather more stable as well as humans body temperatures more stable

Water has a high heat of vaporization:

define:

example of why/how this property is significant in LIVING organisms

-boils (liquid to vapor)

-significant because of the process evaporate cooling which is sweating. Sweating is a process that helps cool us down.

cohesion:

define:

example of why/how this property is significant in LIVING organisms

-stick to other water molecules

-examples is forming water droplets and surface tension

Adhesion:

define:

example of why/how this property is significant in LIVING organisms

-stick to other molecules or surfaces

-examples: waters meniscus. plants uptake water, humans moving water through tissues

solid water is less dense than liquid water:

define:

example of why/how this property is significant in LIVING organisms

-basically ice floats

-freesing fixes hydrogen bonds in place which make its less dense

examples: icebergs, the top of water freezes for bodies of water (think of fish in pond and the insulation created)

Water is an excellent solvent:

define:

example of why/how this property is significant in LIVING organisms

-many molecules are able to dissolve in water

In humans: blood is mostly water, so it can carry nutrients, salts, oxygen, and wastes.

names of 3 terms for solvent

-solvent

-solute

-solution

Explan solvent

the liquid part of a solution

Explain Solute

what gets dissolved in the solvent

Explain Solution

the end result of solvent+solute

water organizes non-polar regions of molecules:

define:

example of why/how this property is significant in LIVING organisms

-some molecules are more polar while others are more non polar

-example on how soap works and phospholipid bilayer

Water dissociates into ions:

define:

example of why/how this property is significant in LIVING organisms

-H2O splits into OH- and H+

-OH- is hydroxide ion which increases the pH and is basic

-H+ is a hydrogen ion which decreases the pH and is acidic

Define the term polar

electrons are shared unequally, making one side slightly positive and the other side slightly negative.

define the term non polar

means electrons are shared equally, so there is no positive or negative side.

define the term hydrophobic

-nonpolar

-doesnt dissolve in water

-water "fearing"

define the term hydrophilic

-polar/ionic

-dissolves in water

-water "loving"

define the term phospholipid

a molecule that makes up the cell membrane. It has a water-loving head and water-fearing tails.

define the term micelle

Micelle = a little bubble that traps oily/nonpolar stuff inside.

-think of micellar water for makeup removal

define the term phospholipid bilayer

two layers of phospholipids that make up the cell membrane. The heads face water and the tails face inward.

pH Scale basic facts (number scale) (lower numbers are acidic or basic) (what is the neutral number)

-number scale: 1-14

-lower numbers are acidic

-higher numbers are basic

-neutral number= 7

what defines an acid?

-a substance that releases H⁺ ions in water.

-Acids have a pH below 7.

What defines a base?

a substance that accepts H⁺ ions or releases OH⁻ ions in water. Bases have a pH above 7.

Is HCI a strong acid or base

strong acid (pH 1-2)

Is NaOH a strong acid or base?

Strong base (pH 14)

What is the pH of blood?

7.35-7.45

What is a buffer?

-keep pH constant/stable

What is the role of buffers in the body?

help the body maintain a relatively constant pH

What is the general equation for the carbonic acid buffer system

H₂CO₃ ⇄ H⁺ + HCO₃⁻

How does the carbonic acid buffer system work?

more basic goes right

more acidic goes left

what is the point of the carbonic acid buffer

This system helps keep blood pH stable.

What are the different ways in which a carbon chain can differ?

-length

-branching

-rings

-double bonds

Define what an isomer is

-same chemical formula but different structure

what are the 3 types of isomers?

1) structural isomers

2) geometric isomers

3)enantiomers

Explain a structural isomer

differ in basic arrangements

Explain Geometric isomer

occur with double bond between carbons

Explan enantiomers

mirror image of each other

What is Natural Selection

survival of the fittest

Who founded natural selection

Charles Darwin

explain the pocket mouse video

-mutation for dark fur

-dark fur is due to natural selection

-camouflaged better from the predators

-lava flow turned terrian for light brown to black

explain the lactase video

-lactose -> came from a mutation

-livestock, famine, people who could digest lactose were more likely to survive and then passed the mutation down

what is the sickle cell example

Sickle cell can be harmful, but people with one sickle cell allele have some protection against malaria. In areas where malaria is common, this allele can stay in the population because it gives a survival advantage.

Describe Sexual selection

organisms have a preference in the mate they choose

describe gene flow

migration of a species so new alleles enters a new population which adds variation

describe genetic drift

Random changes in allele frequencies, especially in small populations.

bottleneck effect

populations size is significantly reduced by enviromental events or human activities

describe mutation

random changes to dna creating new alleles

describe artificial selection

what humans select as characeteristics they want

what are the main differences between prokaryotic cells and eukaryotic cells

Prokaryotic = no nucleus

Eukaryotic = has nucleus

which organisms are prokaryotes

bacteria

which organisms are eukaryotes

plant and animal cells

whats the hierarchy of biological classification

Dumb King Philip Came Over For Great Sandwiches

Dumb-

Domain

King-

Kingdom

Philip

Phyla

Came-

Class

Over-

Order-

For-

Family

Great-

Genus

Sandwiches-

Species

how are living organisms named (bionomial nomenclature)

Example: Homo sapiens

Rules: Genus is capitalized. species is lowercase. Both words are italicized.

explain what subatomic particles are

small particles that make up an atom

proton?

positive charge

makes up half the nucleus of an atom

electron?

negative charge

orbits around the nucleus

neutron?

no charge

makes up half the nucleus of an atom

how do you find the number of protons, neutrons, and electrons of an atom, pratice with a chemical

what is a valenece electron and what does it do?

-electrons in the outermost shell of an atom

-the determine the reactivity of the atom

what is the oclet rule

Atoms are most stable when they have 8 electrons in their valence shell.

what is the law of conservation of matter

What you start with in a reaction must equal what you end with.

what is a covalent bond. give the fun fact

2 atoms share electrons

-fact: they are the strongest bond and hard to break

types of covalent bonds

single, double and triple

what do covalent bonds only occur between

they only occur between nonmetals

what are the two types of covalnet bond

non polar and polar

what is an ion

number of protons doesnt equal the number of electrons

what causes ions to form

Ions form when atoms gain or lose electrons to become more stable.

what is an ionic bond

attraction of ions with opposite charge

what are ionic bonds between?

a metal and nonmetal

does the metal or nonmetal dominate everytime

nonmetal dominates everytime

how to determine the number of electrons in an ion

the atomic number

how to find the net charge of an ion

Protons − electrons = charge

what is a cation

positively charged and lost an electron

what is an anion

negatively charged and gained an electron

what are ions called in the human body

electrolytes

chemical symbol for sodium?

Na

chemical symbol for potassium?

K

chemical symbol of calcium?

Ca

Chemical symbol of carbon

C

Chemical symbol of hydrogen

H

Chemical symbol of oxygen

O

Chemical symbol of sulfur

S