Chapter 1-6 AP Bio

entropy

a measure of quality of energy in the sense that the lower the entropy the higher the quality

what are the properties of life?

order, response to stimuli, reproduction, adaptation, growth and development, regulation, homeostasis, energy processing, and evolution (GRAD HERO REP)

what are the levels of life from smallest to largest?

atom/molecule (not life), organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem, and biosphere

what is a covalent bond?

a bond where two atoms share valence electrons

what is the difference between a nonpolar and polar covalent bond?

nonpolar covalent bonds share electrons equally because same electronegativity, like in a hydrogen diatom

polar covalent bonds share electrons unequally, like H2O

what is polarity in a molecule?

there is one negative end & one positive end

what is hydrogen bonding?

noncovalent attraction between hydrogen & an electronegative atom

what is cohesion?

linking of like molecules

how does cohesion work in water?

water can be transported up cuz water molecules on the leaves pull lower water molecules with them

adhesion

the clinging of one substance to another

how does adhesion work in water?

helps water travel up plants cuz the water adheres to the cell walls by hydrogen bonds & helps counter gravity

surface tension

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

how does surface tension work with water?

at the border between air & water there’s **ordered** arrangement of water molecules, w/ H bonded to one another & water below, so water has high surface tension

capillary action

tendency of water to rise in a thin tube

What are the four macromolecules?

carbohydrates,lipids, proteins, and nucleic acids

dehydration synthesis reaction

two molecules covalently bond by removing water

hydrolysis

Breaking down complex molecules by adding water

what are carbs made of

CHO 1:2:1

what are carbohydrates?

produce/store energy for organisms

monosaccharides

simple sugars; monomers of carbs, like glucose, galactose, fructose

disaccharides

2 monosaccharides like sucrose, malltose, lactose

polysaccharides

more than 2 monosaccharides like starch, chitin, glycogen, cellulose

how are lipids nonpolar?

has hydrocarbons which form nonpolar covalent bonds

fatty acids

chains of carbon atoms bonded to H atoms; monomers of lipids like fats or oils, move and store energy for an organism

fats

three fatty acids linked to one glycerol molecule; solid at room temp

saturated fats

fatty acid molecules that are packed closely together; solid at room temp; straight; no double bonds between carbons; most animal fats; max H atoms

unsaturated fats

bent; liquid at room temperature; not a lot of H, 1 or more double bonds, most plant and fish fats

trans fat

making unsaturated fat to saturated by adding H to solidify it

glycerol

3 carbon alchohol w/ hydroxyl group attached to each carbon

steroids

lipids characterized by a carbon skeleton consisting of four fused rings; reduce inflammation

function of steroids

component of cell membranes (cholesterol), signaling molecules that travel through the body (hormones)

triglycerides

fats/oils glycerol and 3 fatty acids connected by dehydration synthesis; energy source

phospholipids

2 fatty acids (tail: hydrophobic/nonpolar) & phosphate group attached to glycerol (head: hydrophyllic/polar)

function of phospholipids

lipid bilayer of membrane

amino acids

monomers of proteins composed of an amino group and carboxyl group

directionality of protein

amino group to carboxyl group

peptide bonds

the bond between amino acids

polypeptide

polymer of amino acids

amino group

nitrogen bonded to 2 H & to carbon skeleton

carboxyl group

A functional group in organic acids consisting of a single carbon atom double-bonded to oxygen atom & bonded to a hydroxyl group.

20+ amino acids

determined by their r group, categorized as hydrophobic with nonpolar side chains, hydrophilic with polar side chains, or hydrophilic with electrically charged side chains

primary protein structure

a protein as it appears as a sequence of amino acids

secondary protein structure

amino acids linked by H bonds & coils/foils in polypeptide chain; 2 types: aplha (helix) beta (pleated sheets)

tertiary protein structure

3D shape of a protein due to side chain (R) interactions

quaternary protein structure

protein consisting of multiple polypeptide

what happens to a protein that loses its structure?

the protein loses its three-dimensionalness and goes back to a string of amino acids

what can cause protein denaturation

changes in pH, salt concentration, temp, or other environmental factors (changes structure/function)

monomer of nucleic acid

nucleotide

what are the three parts of a nucleotide?

a nitrogenous base, five-carbon sugar, and phosphate group

gene expression

allows organisms to reproduce and pass along their genes, provides instructions for its own replication, directs RNA synthesis, and controls protein synthesis through RNA

DNA

genetic material organisms inherit from their parents

how many bonds between A & T

2

how many bonds between C & G

3 (harder to separate)

why is DNA antiparallel

one side is 5’ > 3’ while the other is 3’ > 5’ (we can only add to 3’)

RNA

genes on a DNA molecule direct mRNA synthesis; the mRNA then interacts with ribosomes to produce proteins

what parts of nucleotide make the steps of the ladder

nitrogenous base

what parts of a nucleotide make the sides of the ladder

phosphate and sugar

flow of info to make proteins

DNA--\>RNA\---\> protein

why is DNA replication semi-conservative

must keep half of DNA to be able to replicate it (for example 30 A & 20 G = 20 C & 30 T)

what is the difference between a prokaryotic and eukaryotic cell?

prokaryotes are unicellular organisms without nuclei, eukaryotes are multicellular with nuclei

differences between plant and animal cells

Plant cells have chloroplasts, a cell wall, and vacuoles while animal cells don’t

structures that all cells have

a cell membrane, cytoplasm, DNA, and ribosome

nuclear envelope

encloses the nucleus and separates its contents from the cytoplasm

nuclear lamina

A netlike array of protein filaments lining the inner surface of the nuclear envelope; helps maintain the shape of the nucleus.

chromosomes

units of discrete DNA organization

chromatin

complex of DNA & proteins that make up chromosomes

nucleolus

prominent structure in nuclei that appears as granules and fibers adjoining chromatin

Ribosomes

site of protein synthesis

endoplasmic reticulum

A system of membranes that is found in a cell's cytoplasm & assists in the production, processing, and transport of proteins and in the production of lipids.

smooth er

ER that has no ribosomes

rough er

ER that is dotted with ribosomes

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell

Lysosomes

carry out intracellcular digestion

cell membranes

the semipermeable membrane surrounding the cytoplasm of a cell with hydrophilic heads and hydrophobic tails

fluid mosaic model

model that shows how a membrane is a mosaic of protein lolecules bobbing in a fluid bilayer of phospholipids

aquaporins

channel proteins that allow the passage of water through the plasma membrane

tonicity

the ability of a surrounding solution to cause a cell to gain or lose water

isotonic

when the concentration of two solutions is the same

hypertonic

when a cell gains water in a solution because it has a higher salinity than the solution

hypotonic

when a cell loses water because it has a lower salinity than the solution

facilitated diffusion

Movement of specific molecules across cell membranes through protein channels

what cells can diffuse through a membrane?

small,uncharged, hydrophobic molecules

what cells need energy to diffuse through a membrane?

charged molecules like ions, water, and polar molecules

phagoctyosis

when a cell engulfs a particle by extending pseudopodia around it and packaging it into a food vacuole

pinocytosis

when a cell continually gulps droplets of extracellular fluid into tiny vesicles

receptor mediated endocytosis

The movement of specific molecules into a cell by the inward budding of membranous vesicles containing proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances.

exocytosis

when particles are enclosed in a vesicle and released from a cell

catabolic pathways

Metabolic pathways that release energy by breaking down complex molecules into simpler compounds;increase entropy

anabolic pathways

Metabolic pathways that consume energy to build complicated molecules from simpler ones;decrease entropy

how does the first law of thermodynamics apply to life?

when an organism dies its energy is released as energy for its predator or heat

entropy

a measure of molecular disorder, or randomness

how does atp work?

atp powers cellular processes by adding a phosphate group to another molecule to activate it

exergonic reactions

proceeds with a net release of free energy and is spontaneous

endergonic reactions

Endergonic reactions are those in which the products have more energy than the reactants, so energy is required as an input; unspontaneous

what do enzymes do?

they lower activation energy of reactions by acting as catalysts

substrate

the reactant an enzyme acts on

cofactors

amino acids that are tightly bound to the enzyme and bind loosely along the substrate to assist in catalysis

coenzyme

If the cofactor is an organic molecule.

competitive inhibitors

bind to the active site of an enzyme, by mimicing the substrate and blocking the real substrate from entering the active site

noncompetitive inhibitors

bind to the enzyme and impede the reaction by changing the enzyme's shape