BIOFOUND 2.3 Biological Molecules pt 3

polymer

chains of smaller repeating molecules

monomers

a small molecule used to build chains

dehydration synthesis

used to make new polymers from smaller building blocks, forms a covalent bond between two molecules by removing two hydrogen atoms and an oxygen atom

hydrolysis

used to break apart large polymers into their building blocks, breaks a covalent bond between two molecules by adding two hydrogen atoms and an oxygen atom

proteins

built from amino acids

carbohydrates (sugars)

built from monosaccharides

lipids (not polymers)

built from fatty acids

nucleic acids (DNA and RNA)

built from nucleotides

monosaccharides

one of the three major groups of carbohydrates: made of one sugar molecule

disaccharides

one of the three major groups of carbohydrates: made up of two sugar molecules held together by a covalent bond

polysaccharides

one of the three major groups of carbohydrates: made up of three or more sugars held together by covalent bonds in a large polymer

hexoses

these monosaccharides have a molecular structure with 6 carbon (C₆H₁₂O₆)

glucose

a hexose that is the major energy source for most living organisms

fructose

a hexose that is the energy source naturally found in high quantities in plants

galactose

a hexose that is the energy source naturally found in high quantities in milk

pentoses

these monosaccharides have a molecular structure with 5 carbons (C₅H₁₀O₅)

deoxyribose and ribose

both of these are pentoses that are used primarily as part of the molecular structure of nucleic acid molecules

sucrose

a disaccharide that is a combination of glucose and fructose (fruit sugar or table sugar)

lactose

a disaccharide that is a combination of glucose and galactose (milk sugar)

maltose

a disaccharide that is a combination of two glucose molecules (grain sugar)

by using hydrolysis reactions to break the covalent bond

how do we digest disaccharides?

by the process of dehydration synthesis

how are polysaccharides formed?

glycogen

the most important polysaccharide in human physiology, made up of thousands of covalently bonded glucose molecules

liver and muscle, for energy

what part of the human body stores glycogen and what for?

energy creation and storage

one of the main carbohydrate functions: glucose is the main form of sugar, though many others can be used, carbohydrates are stored as glycogen

cell communication

one of the main carbohydrate functions: cells carry carbohydrate based tags on the surface of the plasma membrane to identify themselves to other cells

building body structures

one of the main carbohydrate functions: when cells are used to build larger structures (like tissues or organs) carbohydrates are used to stick cells together and act like a molecular glue

pentose sugar

one of the three molecular parts of nucleotides: either ribose (RNA) or deoxyribose (DNA)

phosphate group

one of the three molecular parts of nucleotides: phosphorus surrounded by four oxygen atoms (PO₄)

nitrogenous base

one of the three molecular parts of nucleotides: different on each type of nucleotide

function of deoxyribonucleic acid (DNA)

carries instructions for making all proteins

strand, each strand has millions of nucleotides

what is each DNA polymer called and what does it contain?

in a double helix form (two spirals)

how are all DNAs shaped?

because DNA is two polymers held together by hydrogen bonds

why is DNA double stranded?

ATP

a nucleotide with three phosphates instead of one

adenosine triphosphate

what does ATP stand for?

when a cells metabolism creates energy, it is temporarily stored by forming extra covalent bonds between phosphates. when the bonds are broken they release a lot of energy which is then used by the cell to do cellular work

how do cells use atp?

transport work

one of the three types of cellular work: moving molecules into or out of or around cells (ex. excretion of waste into urine)

mechanical work

one of the three types of cellular work: physical movement of protein and cells (ex. muscle contraction)

chemical work

one of the three types of cellular work: performing chemical reactions as part of metabolism (ex. anabolic reactions that form new molecules require cells to spend their energy stored in ATP)

made from fatty acids, hydrophobic, not polymers

three chemical properties of lipids

hydrophobic effect

the clumping of lipids comes from what?

hydrocarbon chain

one of the two parts of a fatty acid: a long chain of carbon and hydrogen, bonds between carbon and hydrogen are non-polar and so hydrocarbon chains are very hydrophobic

carboxyl group

one of the two parts of a fatty acid: an organic acid, same group that can be found in amino acids, used to form covalent bonds with other molecules to build larger lipid molecules

triglycerides

the simplest lipids in the body, built from three fatty acids linked by covalent bonds to a small molecule called glycerol

energy storage, they store more energy per gram than glycogen and they do not require water

what are triglycerides used for and why?

phospholipid

very similar to triglyceride except for one of the fatty acids are replaced with a hydrophilic head group

amphipathic

molecules that are part hydrophilic and part hydrophobic

causes them to clump in a unique way

how does the hydrophobic effect change phospholipid molecules?

phospholipid bilayer

the unique way a phospholipid clumps

they clump together in the middle so they can separate from the water

what happens to the fatty acids tails in a phospholipid bilayer?

they face the water on either side of the bilayer

what happens to the head groups in a phospholipid bilayer?