Chapter 2 - Chemical components of cells

polymer

Long molecule made by covalently linking multiple identical or similar subunits (monomers).

Subunit

A monomer that forms part of a larger molecule, such as an amino acid in a protein or a nucleotide in a nucleic acid. Can also refer to a complete molecule that forms part of a larger molecule.

The distribution of elements in the Earth's crust differs from

the human body

Humans: lots of H

Earth: lots of O

ionic bond

electrons are donated

covalent bond

electrons are shared

electrons in covalent bonds are shared

unequally (partially neg or pos)

noncovalent bond

does not involve the sharing of electrons; singly are relatively weak, Examples are hydrogen bonds and van der Waals attractions.

hydrophobic force

A noncovalent interaction that forces together the hydrophobic portions of dissolved molecules to minimize their disruption of the hydrogen-bonded network of water;

acid

releases a proton when dissolved in water and created hydronium ions, lowering pH

base

accepts a proton when dissolved in water, usually nitrogen containing purines in DNA/RNA

methyl

--CH3

hydroxyl

--OH

carboxyl

--COOH

carbonyl

--C=O

phosphoryl

PO3 2-

amino

-NH2

carbohydrate monomer

monosaccharide or sugars (glucose) --OH

carbohydrate polymer

disaccharide, polysaccharide (sucrose, glycogen, starch)

condensation reactions

a chemical reaction in which two or more molecules combine to produce water or another simple molecule, BUILDS

--energetically unfavorable

glycosidic bond

covalent bond between two monosaccharides

fatty acid/palmitic acid structure

1. long hydrocarbon chain and is hydrophobic

2. carboxyl group (--COOH) and acts as an acid, and in aqueous it is --COO- and is hydrophilic and reactive

fatty acids have both

hydrophobic and hydrophilic components

saturated palmitic acid

max number of H and NO double bonds

unsaturated palmitic acid tails

one or more double bonds and created kinks

-cannot pack together

fatty acids are stored as

glycerol in the cytosol

lipids are insoluble in

water (hydrophobic)

lipids are soluble in

fat and nonpolar organic solvents like benzene

phosopholipid bilayer

hydrophilic head facing towards aqueous environment and hydrophobic fatty acid tails facing inwards

fatty acid groups

--OH and -COOH or -COO-

amino acids are the monomers

proteins

all animo acid groups

-COOH and --NH2

protein is a polymer made of

monomers of animo acids

peptide bonds

Covalent bonds linking amino acids in proteins.

peptide bonds are formed by

condensation bonds

polypeptide

A polymer (chain) of many amino acids linked together by peptide bonds.

nucleic acid monomers

nucleotides

nucleic acids polymers

DNA and RNA, polynucleotides

nucleotide structure

5 carbon sugar (ribose or deoxyribose), phosphate group, nitrogenous base

ribonucleotides

Nucleotides containing ribose sugar (RNA monomer)

deoxyribosenucleotides

nucleotides containing deoxyribose sugar (DNA monomer)

Pyrimidines

Cytosine, Thymine, Uracil derived from 6-ring pyrimidine ring

purines

Adenine and Guanine 5-ring

ATP structure

adenine (nucleotide), ribose, 3 phosphate groups

phosphodiester bonds

Bonds between phosphate group and pentose sugar in nucleic acids.

DNA double helix structure

composed of 2 polynucleotide chains that run in opposite directions and held together by H bonds between bases

polymers grow by

Addition of a monomer onto one end of the polymer chain by condensation rxn

the function of polymers are determined by

sequence of monomers/subunits

shape and sequence of macromolecules determines

the function

what is needed to form a macromolecular assembly such as a ribosome

covalent and noncovalent bonds

nucleotides function

-energy transfer (ATP)

-forma RNA and DNA molecules

How is protein, RNA, and DNA molecules formed

from monomers/subunits by condensation reactions

noncovalent bonds

Weak chemical bonds in which no electrons are shared

Ex: hydrogen bonds, van der Waals

how do protein chains fold?

noncovalent attractions

how do macromolecules bind to other molecules?

noncovalent attractions

electrostatic attraction

the attraction between positive and negative charges Ex: ionic bonds and polar covalent bonds