Lecture 1/8 and 1/10 (1)

Characteristics of a cell

• Highly complex/organized

• Contain info and tools to act on it

• Capable of producing more of themselves

• Acquire and use energy

• Carry out variety of chemical rxns

• Engage in mechanical activities

• Respond to stimuli

• Capable of self-regulation

• Evolve

cell theory

• all organisms are composed of one or more cells

• cell is the structural unit of life

• cells arise only by division from a preexisting cell

• cells contain genetic information passed to the next generation

four types of molecules commonly found throughout cells

* carbohydrates (sugars)
* lipids (fats)
* amino acids (proteins)
* nucleic acids (dna/ rna)

monosaccharides (simple sugars)

most basic units of carbohydrates

general formula for sugars

(CH2O)n

structure of simple sugars

carbon backbone in a linear array. each carbon is linked to a hydroxyl group except one. one C has a carbonyl

glycosidic bonds

how sugars (monosaccharides) link. bond forms between the C of one sugar and OH group of another sugar

disaccharides

two monosaccharides joined together

examples of disaccharides

sucrose, lactose, maltose

polysaccharides

polymers of monosaccharides

functions of carbohydrates

• storing chemical energy

• stable building block for other molecules

lipids dissolve in

organic molecules, not water, meaning they're nonpolar

fatty acids

long, unbranched hydrocarbon chains with a single carboxyl group at one end

saturated

fatty acids lacking double bonds

unsaturated

fatty acids with double bonds

fats structure

glycerol linked by ester bonds to three fatty acids

more double bonds in a fat

lowers the melting point

fats

rich in chemical energy, have both hydrophobic and hydrophilic properties

steroids

hydrophobic and insoluble

phospholipid structure

resemble fats in structure, but only have two fatty acid chains. third hydroxyl of glycerol is attached to a phosphate group

proteins

large macromolecules of amino acids

amino acid structure

carboxyl and amine group, separated by an alpha C. there is an R group bonded to the alpha C

peptide bond

bond between amino acids. formed between the carboxyl group and amino group

nucleotide structure

phosphate group, 5 C sugar, and nitrogenous base on 1' C

ribose structure

OH on 2' C

deoxyribose structure

H on 2' C

phosphodiester linkage

• links nucleic acids

• hydroxyl group on 3' C is bonded to phosphate group on 5' C

• forms sugar phosphate backbone

purine

• 2 rings

• A, G

pyrimidine

• 1 ring

• C, T, U

which bases are involved in energy?

A and G