ap bio exam review

trace elements

required for an organism, but only in small amounts

isotopes

an atom with the same number of protons but a different number of neutrons in the nucleus

smaller

electrons are significantly (smaller/larger) than protons and neutrons.

ionic bond

bond formed between 2 atoms when 1 or more electrons are transferred from one atom to the other; results from attraction of opposite charges

ions

charged forms of atoms

covalent bond

bond where electrons are shared between atoms

nonpolar covalent

electrons are shared equally between atoms

polar covalent

electrons are shared unequally between atoms

polar

water is a (non polar/polar) covalent molecule.

the positive and negative charges from it being a polar molecule strongly attract.

why do water molecules readily stick together?

hydrogen bonds

weak chemical bonds that form when a hydrogen atom that is covalently bonded to one electronegative atom is attracted to another

hydrogen

what bonds is water held together by?

they become strong

what happens when there are several hydrogen bonds compared to a single bond?

solvent

capable of dissolving many kinds of substances

cohesion and adhesion

how is water able to move up the stems and branches of plants?

capillary action

occurs in thin vessles, movement of substances (water)

acidic

contains many hydrogen ions

alkaline/basic

release hydroxide ions into a solution

soap

example of a common base

10, 10

a change in the pH scale is done on an increase of x____, which means a change from 3 to 4 is ___x more basic.

high

a low concentration of hydrogen ions means a (low/high) pH.

organic compounds

carbon atoms surrounded by hydrogen atoms

NaCl

example of an inorganic compound

polymers

chains of building blocks

monomer

individual building blocks of a polymer

dehydration synthesis/condensation reactions

a water molecule is lost and a larger compound is formed; hydrolysis can also occur

hydrolysis

polymers are broken down into monomers; the water breaks the bond between 2 monomers

carbohydrates

organic compoiunds that contain carbon, hydrogen, and oxygen; usually in a 1:2:1 ratio

sugar

saccharide

a carbohydrate made up of a single saccharide (sugar); serve as an energy source for cells

monosaccharide

C₆H₁₂O₆

glucose and fructose chemical formula

fructose

common sugar found in fruits

disaccharides

hydrogen from one sugar molecule combines with the hydroxyl group (-OH) of another sugar molecule, creating water

glycosidic linkage

when 2 monosaccharides are joined to form a dissacharide

storage of sugar

glycogen and starch functions

cellulose

made up of beta glucose; major part of cell walls in plants; lends structural support

chitin

a polymer of beta glucose molecules that acts as a structural molecule for the walls of fungi and exoskeletons

an amino group (-NH₂), a carboxyl group (-COOH), a hydrogen, and an R-group

what are the 4 parts of an amino acid?

R-group/side chain

only part of an amino acid that varies

the side chain/r group

what part of an amino acid affects if it’s hydrophobic or hydrophilic?

hydrophobic

non-polar and uncharged

hydrophilic

polar and uncharged

dipeptide

when 2 amino acids join

peptide bond

bond formed between 2 amino acids

polypeptide

form in the shape of a string; group of amino acids joined together

protein

polypeptide chain twists and folds in on itself to form this 3D structure

primary structure

linear sequence of amino acids

secondary structure

polypeptide twists, coils, or zigzags

r groups are interacting with one another

why does a polypeptide fold and twist?

tertiary structure

amino acids far from the primary structure interact

quaternary structure

several polypepetide chains interact to form this structure

hemoglobin

molecule in the blood that helps distribute oxygen to tissues in the body

chaperone proteins (chaperonins)

help the protein fold properly and make the process more efficient

lipids

consist of carbon, hydrogen, and oxygen atoms; exs: triglycerides, phospholipids, and steroids

due to nonpolar structure, they act as structural components of cell membranes, an insulation source, signaling molecules, and energy storage

function of lipids

triglycerides

made of a glycerol molecule and 3 fatty acid chains

saturated fat

a fatty acid with hydrogens along its carbon chain; may have a few gaps where double bonds exist instead of hydrogen

unsaturated fat

fatty acid where there’s a double bond in the chain

more

(more/less) double bonds in a lipid makes it more unsaturated.

linear, solids

saturated fatty acids have a _______ structure, meaning they tend to form _______.

phospholipid

have 2 fatty acid tails and a negatively charged phosphate head; both hydrophobic and hydrophilic

amphipathic molecule

molecules that are both hydrophobic and hydrophilic

cholesterol

type of lipid with a four-ringed structure; increases membrane fluidity; holds things together at high temperatures

nucleic acids

contain carbon, hydrogen, oxygen, nitrogen, and phosphorus

higher

smaller cells have a (higher/lower) surface area to volume ratio, which allows them to more efficiently exchange outside materials.

decreases, less

as cells increase in volume, the surface area to volume ratio (increases/decreases), and the exchange of materials becomes (more/less) efficient.

prokaryote

bacteria and archaea, for example; fairly simple

one continuous circular strand of DNA found freely in the nucleoid

what does the genetic material in a prokaryote look like?

cell wall

composed of peptidoglycans, found in prokaryotes

plasma membrane

lipid layer of a prokaryotic cell

false

t/f: prokaryotes don’t have ribosomes.

flagella

long projections used for movement

capsule

feature found in prokaryotes outside of the cell wall that gives extra protection

plasma membrane

double-layered structure made up of phospholipids and proteins

phospholipid bilayer

2 lipid layers form an hydrophobic sandwich

regulates movement into/out of cell; semipermeable

function of the plasma membrane

semipermeable

only certain molecules can pass (mostly small hydrophobic molecules)

peripheral proteins

protein associated with the lipid bilayer that are located on the inner or outer surface of the membrane

integral protein

protein firmly bound to the plasma membrane; amphipathic;

transmembrane proteins

integral proteins that extend all the way through the membrane

fluid mosaic model

each layer of the phospholipids is flexible and it is peppered with different protein and carbohydrate chains

adhesion proteins

form junctions between adjacent cells

receptor proteins

ex: hormones, act as docking sites for arrivals at the cell

channel proteins

form channels that selectively allow the passage of certain ions or molecules

cell surface markers

exposed on the extracellular surface; play a role in cell recognition and adhesion

carbohydrate side chains

attached to the outer surface of some proteins

nucleus

largest organelle; directs cell action; determines reproductive ability; houses DNA

chromosomes

DNA organized into large structures

nucleolus

where tRNA is made and ribosomes are assembled

ribosomes

site of protein synthesis; round structure composed of a large and small subunit; composed of rRNA and proteins; can free float or be attached to the ER

endoplasmic reticulum

continuous region that extends to many regions of the cytoplasm, provides mechanical support, aids in intracellular transport

rough ER

attached to the nucleus; studded with ribosomes; compartmenalizes the cell; proteins generated here are moved to or across the membrane or they are used to build golgi, lysosomes, or the ER

smooth ER

lacks ribosomes; makes lipids, hormones, and steroids; breaks down toxic chemicals

golgi complex

modifies, processes, and sorts proteins; packages and distributes materials to be sent out of the cell; lysosome production

vesicles

golgi packages final products in these little sacs, which carry products to the plasma membrane

mitochondria

power stations responsible for converting energy from organic molecules into useful energy; most commonly ATP

cristae

folds inside the mitochondria; where most of ATP production is done

increasing the surface area of making ATP

haivng folds in the mitochondria helps with…

lysosomes

carry digestive enzymes which break down old organelles and debris; essential for apoptosis

centrioles

small, paired, cylindrical structures found within microtubule organizing centers; most active during cell division