Biology Module 1

Type I error

false positive

Type II negative

false negative

correlation

connection between two different ideas

causation

something that produces an effect

Theory

unifying explanation for observations, explains why/how

Scientific law

explanation of an observation under certain conditions, explains what

Levels of biology (from largest to smallest)

biosphere, ecosystem, community, population, organism, organ, tissue, cell, molecule, atom

What 5 things do all living organisms have in common

require materials and energy, maintain homeostasis, respond to their environment, reproduce and develop, adapt and evolve

cell metabolism

sum of all chemical reactions that lead to energy production

examples of homeostasis

temp regulation, moisture regulation, pH regulation, sugar level regulation

what is homeostasis controlled by?

feedback systems in the organism

What ensures an organism’s survival?

responding to the environment

The responses to the organisms environment are known as

behaviors

why are mutations beneficial to life?

they increase population diversity

why do organisms adapt?

to better function in their environment

evolution

a series of adaptations over time that lead to genetic changes

What are the three parts of atoms?

protons, electrons, neutrons

What identifies the isotope of an atom

neutron

What makes up the nucleus of an atom?

protons and neutrons

What part of the atom is constantly moving, so much so that we can never precisely identify where they are?

electrons

Electron shell

an energy level where electrons orbit a nucleus

electrons in shells ______ farther away from the nucleus have more _____ energy than electrons closer to the nucleus

farther, potential

Where does the chemistry happen in the atom

valence shell

compounds

molecules made up of different atoms

how do atoms form bonds with each other?

electrons

what are the two types of bonds?

covalent bonds and ionic bonds

ionic bond

when two atoms bond, the more electronegative atom strips a valence electron away from the less electronegative atom

What happens in an ionic bond once the electrons are shared?

the two atoms become ions, having either a net negative or net positive charge

What happens to the more electronegative atom in an ionic bond?

It now has one extra electron and carries a negative charge (anion)

What happens to the less electronegative atom in an ionic bond?

it now has one less electron and carries a positive charge (cation)

How are atoms held together in ionic bonds?

by their electrostatic interactions

Whats another name for compounds with ionic bonds?

salts

Examples of ionic compounds

NaCl, CaCl2, KCI, MgCl2

Covalent bond

when two atoms share a pair of valence electrons

Which is stronger, Ionic or covalent?

Covalent

Non-polar covalent bonds

the attraction for the electrons by the nuclei in a covalent bond is equal

Polar covalent bond

the attraction for electrons by the nucleus is unequal

Where do shared electrons in polar covalent bonds spend more time in?

the orbital of the nucleus of the more electronegative atom

What two elements are very electronegative?

Oxygen and Nitrogen

What type of bond does Oxygen and Nitrogen form with Carbon and Hydrogen?

polar covalent

What type of bond does carbon and hydrogen form with each other?

non-polar covalent

What percent of body mass does oxygen make up?

65

What percent of body mass does carbon make up?

18.5

What percent of body mass does hydrogen make up?

9.5

What percent of body mass does Nitrogen make up?

3.3

Hydrogen bonds

weak bond when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another atom

What forms Van Der Waals bonds?

a molecule with a non-polar covalent bond’s electrons are constantly moving around, allowing it to have temporarily positive/negative charged regions

Is water polar or non-polar?

polar

What atom in water carries a partial negative charge?

oxygen

What atom in water carries a partial positive charge?

Hydrogen

Hydrogen bonds form and break with ____ frequency

high

Hydrogen bonding orders water molecules into ________

a high level of structural organization

What are the properties of water?

cohesion, temperature moderation, floating ice, excellent solvent

What makes the cohesion of water molecules so strong?

Hydrogen bonds

Cohesion

linking together of like molecules

adhesion

water molecules forming hydrogen bonds with other non water molecules

Cohesion contributes to the _______________

transport of water and dissolved nutrients against gravity

Adhesion of water to cell walls does what?

helps counter the downward pull of gravity

surface tension

how difficult it is to stretch or break the surface of a liquid

What gives water a high surface tension?

Hydrogen bonds

How does water moderate temperature?

Absorbing heat from warmer air, releasing heat into cooler air

heat (energy)

thermal energy in transfer from one body of matter to another

Temperature

average kinetic energy of the atoms and molecules in a body of matter

Specific heat

amount of heat that must be absorbed or lost for 1g of a substance to change its temperature by 1 degree celcius

Specific heat of water

1 cal/g

Alcohol specific heat

0.6 cal/g

Why is water’s specific heat so high?

hydrogen bonding

When hydrogen bonds break

heat is absorbed

When hydrogen bonds form

heat is released

percent of earth covered in water

70-75 percent

earth ________ heat during the night

releases

earth ________ heat during the day

absorbs

How do organisms stay cool?

evaporating cooling

evaporating cooling

when water molecules evaporate, the remaining liquid water is cooler. molecules with the most kinetic energy leave the liquid phase

When ice forms what cannot be broken?

the hydrogen bonds

when can hydrogen bonds break and reform?

just above freezing, allows molecules to be more tightly packed

Above what temperature does water behave like other liquids?

4 degrees celcius

water __________ as it warms

expands

water _______ as it cools

contracts

Why is floating ice essential to organisms living in the water?

it insulates the water below

Solution

homogenous mixture of two or more substances

Solvent

dissolving agent of a solution

Solute

substance that is dissolved in a solution

A _________ dissolves in a _________ to make a _________

solute, solvent, solution

What makes water a powerful solvent, especially for salts?

the polarity

What atoms are attracted to cations?

oxygen

What atoms are attracted to anions?

Hydrogen atoms

Water molecules form what around each ion of the salt?

hydration shell

Water dissolves what type of molecules?

polar

Do amino acids have charges?

some

How is a hydration shell formed?

water molecules interact with the charged surface of a protein

Hydrophillic

water loving, salts, charged particles, and polar molecules (amino acids) will dissolve in water

Hydrophobic

water fearing, oils, non polar amino acids (fats), will not dissolve in water

What types of molecules can’t form hydrogen bonds?

nonionic and non-polar

What happens when a water molecule breaks apart

creates ions like a salt

What happens when a hydrogen atom participating in a hydrogen bond shifts from one molecule to another?

it leaves it’s electron behind, transferring an H+ ion (proton)

Hydroxide ion

water molecule that lost its proton

Only ___ water molecule in every ____ dissociates into ions

1, 10 million

Acid

substance that increases H+ concentration of a solution

What disassociates into H+ and Cl- in water, increasing the concentration of H+

HCl