AP/DC Biology Unit 1

The three main types of bonds are?

Covalent (strongest), Ionic Bonds, Hydrogen bonds (weakest)

Covalent Bonds

Form molecules, may be polar or non polar

Polar

unequal sharing of electrons due to one atom having greater electronegativity than the other, such as in water

non polar

equal sharing of electrons such as in oxygen gas

Ionic bonds

form ionic compounds or salts due to the formation of anions (negative ions) and cations (positive ions). Relatively weak in water (dissociate)

Hydrogen Bonds

form between the positively charged hydrogen atom of one molecule and the strongly electronegative oxygen or nitrogen of another molecule. Responsible for many of water’s special properties.

Van der Waals

interactions, disulfide bonds. Form due to the asymmetrical distribution of electrons within a molecule. These weak connections contribute the the 3D shape of large molecules, like proteins

chemical reactions

make and break bonds

cohesion

linking of like molecules allows for surface tension

adhesion

clinging pf one substance to another

transpiration

loss of water through leaves of a plant

high specfifc heat

the amount of heat required to raise or lowers the temperature of a substance by 1c. high specific heat means that, compared to other materials water changes less when a given amount of heat it lost or absorbed

solvent

substance that something is dissolved in

hydrophilic

water fearing, soluable in water, polar, ionic

hydrophobic

water fearing, insoluable in water, non polar

explain how the properties of water that result form its polarity and hydrogen bonding affect its biological function

allow living organisms to transport nutrients, regulate internal temp, and perform chemical reaction

DNA

based on genetic code made of nucleic acids, all life on earth shares the same genetic code, the molecule that carries the genetic instructions used in the growth, development, functioning, and reproduction of all living organisms

Prokaryotes

no nucleus

Eukaryotes

has nucleus and membrane bound organelles

stimulus

respond to their envrionment, an organisim reacts to stimuli following a pathway through the bpdy to produce a response

homeostasis

process by which organisims maintain a relatively stable internal environment

describe the characteristics of life

cellular organization, metabolism, homeostasis, growth and development, reproduction, response to stimuli, and evolution

electron configuration

4 valence electrons, determines the number of kinds of bonds and atom can make, can form up to 4 covalent bonds, can form single, double, or triple covalent bonds.

carbon skeleton

it can form large molecules that are chains, rings, or branched, vary in length or double bond location, leads to diversity

isomers

molecules with same molecular formula by differ in arrangement of atoms. shape affects functional properties and biological function

hydrocarbon

a combination of h and c, nonpolar and stable, usually gasses at room temp, major component of carbohydrates and lipids

biomolecules

all contain carbon

carbohydrates

carbon, hydrogen, and oxygen

lipids

carbon, hydrogen, oxygen and sometimes phosphorus

protein

carbon, hydrogen, oxygen, nitrogen, sometimes sulfur, iron and magnesium

nucleic acids

carbon, hydrogen, oxygen, nitrogen, and phosphurus

macromolecules

polymers built from monomers

polymer

long chain molecules made of repreating subunits called monomers

dehydration synthesis

also called a condensation reaction, water is removed to form large molecules, monomers to polymers

hydrolysis

water is added to split large molecules, reverse od dehydration synthesis reaction, polymers to monomers

functional group

components of organic molecules attachted to the carbon skeletion that are commonly involved in chemical reactions

monomers

single, form polysaccharide

polys