Question | Answer |
What is every physical thing-living or not- made up of? | atoms |
smallest basic unit of life | atoms |
what kind of charge do protons have? neutrons? electrons | protons-positive
neutrons-no charge
electrons-negative |
substance made up of one type of atom and cannot be broken down into simpler substances by ordinary chemical means | element |
how do you identify an element | by number of protons in nucleus->atomic number |
where are elements organized | periodic table |
when is a atom most stable | when its outer energy levels are filled with electrons |
how do atoms become more stable | by bonding with other atoms |
*atoms rarely exists alone | |
what are atoms that have gained or lost an electron | ionic bonds |
if an atom gained an electron what kind of charge does it have | negative |
if an atom lost an electron what kind of charge does it have | positive |
**Positive and negative ions are attracted | |
*Ionic bonds are very strong chemical bonds | |
atoms that have become more stable by sharing one or more pair of electrons with other atoms | covalent bonds |
are covalent bonds weaker or stronger than ionic bonds | weaker but they are still strong |
two or more atoms held together by a covalent bonds | molecule |
what are many substances in living things made up of | molecules |
substances composed of atoms of two or more different elements held together in specific ratios | compounds |
what does water's unique properties allow | they allow life to exist on Earth |
**WATER IS A POLAR COVALENT MOLECULE | |
polar | has charged regions |
nonpolar | has no charged regions |
forms between slightly positive hydrogen atoms and slightly negative atoms | hydrogen bonds |
what does life depend on | hydrogen bonds |
what is cohesion | attraction to stick to same substances of different charges |
what is adhesion | ability of water to attract molecules of different substances |
what makes a drop of water | cohesion and surface tension |
what are the 4 properties of water | water molecules are very polar; water has a high specific heat; ice is less dense than water; capillary action |
what is capillary action | what water moves up thin tubes because of adhesion |
what is 4 reasons why water is important for life | water is a terrific solvent; water has a strong surface tension; water has a relatively high boiling point; is there water on other plants |
why is water a terrific solvent | many ions and polar molecules necessary for life can disolve in water |
what does it mean that water has a high boiling point | it takes a lot of heat energy for water molecules to leave their liquid form held together by cohesion |
formed when one substance dissolves in another | solution |
dissolve other substances and present in greater amount | solvent |
dissolve in a solvent | solute |
do polar solvents dissolve polar or non-polar solutes | polar |
do non-polar solvents dissolve polar or non-polar solutes | non-polar |
what is the pH scale used to determine | the % of hydrogen ions in water |
what has a high Hydrogen concentration and a pH less than 7 | Acids |
what has a low Hydrogen concentration and a pH greater than 7 | bases |
what substance is neutral and has a pH of 7 | water |
what can pH be regulated by | buffers |
compounds that can bind to Hydrogen when Hydrogen concentration increases and can release Hydrogen when the Hydrogen concentration decreases | buffer |
what should the pH in humans stay around | 6.5-7.5 |
if humans have too low of a pH what could that result in | ulcer |
change substances into different substances by breaking chemical bonds and forming new chemical bonds | chemical reaction |
catalysts that speed up reactions in living things | enzymes |
speeds up reactions | catalysts |
-type of protein
-breaks down materials
-ends in "ase"
-lowers activation rate | enzymes |
amount of energy needed for chemical ractions | activation energy |
***Enzymes SPEED UP reactions and LOWER activation energy | |
why do enzymes have a specific shape | so they fit a specific substrate |
something that needs to be broken down | substrate |
temperature and pH can affect the shape of the enzyme which can cause enzyme to not work | denaturization |
why is carbon the element of life | it can bond to many different elements |
3 characteristics of carbon atoms | 1) carbon can bond with itself or other atoms
2) ring or long chain structure
3) often binds to hydrogen atoms (hydrocarbon) |
what is part of 4 main macromolecules | carbon |
large molecules | macromolecules |
what are the 4 main macromolecules | carbohydrates, lipids, proteins, and nucleic acids |
what are the components of macromolecules | monomer- building block
polymer- chain of monomers |
what are carbs made of | Carbon, Hydrogen and Oxygen in a ring |
what is an example of carbs | glucose |
what do carbs do | break down carbs to release usable energy |
what is the monomer of carbs | monosaccharides |
what is the polymer of carbs | disacchardies & polysaccharides |
what are lipids made of | carbon, hydrogen, and oxygen in a chain |
what is an example of lipids | fats and oils |
what do lipids do | store energy and absorbation of vitamins and minerals |
a phospholipid has a hydrophillic head and a hydrophobic tail | |
what are proteins made of | carbon hydrogen oxygen and nitrogen |
what is an example of proteins | enzymes |
what is the monomer of proteins | amino acids |
what is the function of proteins | perform cell functions |
what is the primary structure of proteins | sequence of amino acids |
what is the secondary structure of proteins | fold and helix |
what is the teritary structure of proteins | fold ontop of each other |
what is the quaternary structure of proteins | multiple teritray |
what are nucleic acids made of | carbon hydrogen oxygen nitrogen and a phosphate |
what is an example of nucleic acids | DNA and RNA |
what is the monomer of nucleic acids | nucleotides |
what are nucleotides made of | phosphate, sugar and nitrogen base |
the usable form of energy for cells | ATP (Adenosline Triphosphate) |
when is ATP made | during cellular respiration in the mitochondria |
when energy is released and the bond of the second and third phosphate what does it turn into | ADP |
how do energy molecules and other particles go to where they need to go | through the cell membrane |
regulates what goes in/out of cell | cell membrane |
made of lipid bilayer; selectively permeable
; helps cells maintain homeostatis | cell membrane |
what are the 2 types of cell transport | passive and active |
movement of materials across cell membrane without using energy | passive transport |
* in any solution, solute particles (oxygen/gases) move constantly | |
what are the 2 types of passive transport | diffusion and facilitated diffusion |
particles move from high concentration to low concentration | diffusion |
*ultimate goal is equilibrium | |
concentration is balanced on both sides | equilibrium |
what happens once equilibrium is reached | particles continue to move across in both directions |
passive transport that needs help | facilitated diffusion |
why does water have a hard time passing through membrane | hydrophobic middle |
how does water move | high to low |
same strength | isotonic |
above strength in comparison | hypertonic |
below strength in comparison | hypotonic |
WATER GOES TOWARD HIGHER CONCENTRATION | |
in a hypertonic solution what will have to the cell | it will shrink |
in a hypotonic solution what will happen to the cell | it will swell |
what does the change in water concentration create | osmotic pressure |
movement of water creating a force | osmotic pressure |
movement of particles against a concentration gradient | active transport |
2 types of active transport | molecular & bulk |
uses protein pumps to move calcium, potassium, and sodium
*pumps will change shape | molecular transport |
moving large particles across cell membrane | bulk transport |
materials go into cell | endocytosis |
material leave the cell | exocytosis |
engulfs materials | phagocytosis |
vesicles will pinch off material | pinocytosis |