Biology 1000 Exam #1 - Matthew Kearley

what is the organization of living organisms

atoms, molecules, organelles, cells, tissues, organs, organ system

describe the characteristics of living organisms

have organization

acquire and use energy

maintain constant internal conditions

have inherited information that determines form and function

are composed of 1 or more cells

respond to their environment

all living organisms are going to reproduce

define science

a collection of unified insights about nature, the evidence for which is an array of facts

science does not deal with what kind of truth?

absolute truth

what are facts

explanations that are thought to be true

which scientific sources are considered to be the most reliable? the least?

most: peer reviewed journals

least: internet

list all of the scientific sources best to worst

peer reviewed journals

reviewed texts

science books

science magazines

newspapers/TV

internet

Explain the difference between a theory and a hypothesis

theory: generalization that explains many observations -- has been tested and researchers have yet to fond evidences that disprove it

hypothesis: tentative, testable explanation for an observed phenomenon

describe the steps of the scientific method and be able to apply the scientific method to a given problem

observation

hypothesis

experiment/test

conclusion

independent variables

factor of the experiment being tested

dependent variable

response of change that occurs due to the independent variable

control sample

a sample where the independent variables are omitted

what is the definition of an element

a substance that can't be reduced to a simpler substance (composed of atoms)

definition of an atom

basic unit of matter composed of protons, electrons and neutrons

describe the particles found in an atom

protons: positive, atomic number

neutrons: neutral, no charge

electrons: negative, more or less than protons

what is the definition of a nucleus

very little space, but contains nearly all the mass

given the atomic number, atomic mass, and charge of an atom, list the number of protons, neutrons, and electrons in that atom

protons = atomic mass number

neutrons = mass # - protons

electrons = if negative - more than protons

if positive - less than protons

given the number of electrons, or the atomic # and charge of an atom, determine the # of electrons found in the outer shell of an atom

1) first shell will only have two

2) 8 to make a full shell

3) atomic # = number of shells on the circles

given the mass number and atomic number, determine the number of protons and neutrons

protons = atomic number

neutrons = mass # - protons

define the term isotope

forms of a single element that differs in the number of neutrons

definition of radioisotopes

an isotope that has an unstable nucleus - loss of neutrons from the nucleus

what makes a radioisotope radioactive

it has an unstable nucleus

electrons

very little mass, negative charge (if it's negative then it has one more than proton, if positive it has one less)

ions

atoms that differ in the number of protons and electrons = positive or negative charged atoms

atoms will form _______ to satisfy the requirements of their outer shells

bonds

molecule

number of atoms in a defined spatial relationship

Covalent bonding

bonds in which atoms share electrons positive charge - lower number of electrons than the atomic number

ionic bonding

atoms bonded through attraction of oppositely charged particles (ions) - exchange electrons

polar covalent bonding

shared electrons spend more time neat the larger nucleus, creates a negative charge on 1 end of the molecule

hydrogen bonding

formed when partially positive hydrogen atom in a polar cobalt bond is attracted to a partially negative atom in antlers polar covalent bond

How do solute, solution, and solvent relate to one another?

they all have to work together to figure out which substance is which.

Solution

mixture of two or more substances

solute

substance that is dissolved in a solvent

solvent

the substance in which a solute is dissolved

describe the properties of water

provides the basis for life

freezes at 0 degrees celsius (32 degrees Fahrenheit): ice is less dense than water

has a high specific heat

buffers climates

within a water molecule it is __________ bonds that bond hydrogens to oxygen, and then within water itself _________ bonds water molecules to other water molecules

polar covalent; hydrogen

surface tension

water molecules bond to each other more strongly the to air (hydrogen bonds create surface tension)

hydrophilic molecules

interact with water (ex. salt)

hydrophobic molecules

do not interact with water (ex. lipid)

how are acids and bases defined. How do H+ and OH- ions determine pH? How is pH important to living organisms

acids lower pH and bases raise the pH living organisms usually thrive in a pH of 6-8

acids

lower pH

bases

raise pH

acidosis

lower pH levels in their blood, makes people sick

alkalosis

moved acid, higher pH levels

why is carbon so important in the molecules that make up living organisms?

it keeps things going

water intoxication

too much water can kill you and cause this

if lime (a base) is spread on a field with acidic soil, the the pH of the soil will....

increase

how many covalent bonds can carbon contain

4

if you add ammonia (base) to a neutral solution, the number of OH- ions will....

increase

what are hydrocarbons

a chain of carbons and hydrogens

what are functional groups

the groups of atoms in an organic molecule that usually participate in chemical reactions

how are functional groups important in chemical reactions? Diagram the following functional groups: Hydroxyl, Carboxyl, Amino, Phosphate

they participate in chemical reactions

most organic molecules are what type of units

repeated units

when molecules bond to one another and produce water what is it called

dehydration synthesis

when a more complex molecule is spilt into simpler molecules and water is required it is called what

hydrolysis

when you chew on bread for awhile what begins to happen

it begins to taste sweeter

what is a monomer

a single unit

what is a polymer

string of monomers

describe the characteristics or carbohydrates

contain C,H, and O

monosaccharide (monomer)

polysaccharides (polymer)

how are carbohydrates important to living organisms

they provide many important things

what are the differences between dehydration synthesis and hydrolysis?

dehydration synthesis: makes non water into water

hydrolysis: makes water into non water

what are the 4 main things in a polysaccharide

starch

glycogen

cellulose

chitin

what is a starch

carbohydrate storage in plants, digestible by animals

what is glycogen

how animals store carbohydrates

what is cellulose

primary structural component of plants (provides rigidity). Animals can't digest, only bacteria can

what is chitin

strengthens the exoskeleton of many organisms (ex. Insects and arthropods)

what are the characteristics of lipids?

composed of C,H, O

hydrophobic

energy storage, insulation

what is fat

a type of lipid (fatty acids + glycerol)

what is a fatty acid

a carboxyl and a long hydrocarbon chain

how are lipids important to living organisms?

the store energy

describe the different type of lipids

fat: saturated and unsaturated

steroids: 4 linked carbon rings

what are the differences between saturated fatty acids and unsaturated fatty acids?

saturated: all C-C bonds are single bonds (donuts, fries)

unsaturated: at least one C-C bond is a double bond (avocados, fish)

what is a phospholipid

a type pf lipid; makes up the outer membranes of cells

what are the characteristics of proteins?

they consists of polypeptide chains made up of amino acids

what is a protein

polymer commode of many amino acids

list 4 things about proteins

all amino acids have an amino group and a carboxyl group attached to a central carbon

proteins consist of polypeptide chains made up of amino acids

protein functions are numerous and depend on the proteins shape

change in the environment can change the shape of a protein = denature the protein

how are proteins important to living organisms?

they transport lipids in and out of the bloodstream

what is a lipoprotein

a capsule surrounded by a globule of lipid

why is a lipoprotein important

it transports lipids in and out of the bloodstream

LDL - low density lipoprotein ( carry cholesterol to coronary arteries of the heart)

HDL- high density lipoprotein ( carry cholesterol to liver - away from heart)

You want a high LDL and a low HDL

what are the functions of DNA and RNA?

RNA: takes DNA encoded instructions to the sites in cells where proteins are put together

DNA: contains the instructions to the sites in cells where proteins are put together

DNA and RNA are composed of _______

nucleotides

nucleotides are composed of what

a phosphate groups, a 5 carbon sugar, and a nitrogen base ( Guanine, Cytosine, thymine, and adenine)

what does a fatty acid look like

this-

what does a steroid look like

this:

what does an amino acid look like

this

prokaryotic cells

bacteria, no nuclei, single celled, many don't use oxygen, no organelles

eukaryotic cells

everything else, nuclei, many are multicellular, most use oxygen, organelles

what is a plasma membrane

outer boundary of the cell

what is cytoplasm

region inside the plasma membrane and outside of the nucleus

what are organelles

structures within the cells which carry out specific functions

what is a nucleolus

it is within the nucleus - RNA and proteins combine to make ribosomal subunits

what is cytosol

fluid in which cell's organelles are immersed outside of the nucleus

what is a ribosome

a structure that translates RNA to proteins

list and describe the components of the cytoskeleton

internal scaffolding that maintains the shape of a cell

distinguish between plant and animal cells. What structures do they share, which are different?

plant cells: starch is a storage, cellulose is their primary structure, chitin strengthens the exoskeleton

animal cells: starch is digestible, animals can't digest cellulose

what is the Golgi complex

consists of membranous sacs. received proteins from the ER, modifies them and then ships them off to their final destination

what is a vesicle

tiny membrane sacs in the cytoplasm

what is a lysosome

organelles that contains enzymes that break down organelles and return them to the cytosol so they can be reused -- also digest nutrient

what is a peroxisome

vesicle containing enzymes which break down fatty and amino acids

what is a mitochondria

it converts energy found into a molecular form ATP that the cell can use