ch. 5 lecture notes
Cholesterol
-most common steroid in humans -precursor to steroid hormones, such as reproductive hormones -mostly insoluble in water -found in bile
What is different between fats and phospholipids
1. phospholipids have only 2 fatty acid tails instead of 3 2. phospholipids have a polar group 3. phospholipids usually have at least one unsaturated bond
Carbohydrates follow what formula?
1:2:1 for C:H:O
What do steroids look like
4 carbon rings
hydroxyl group of carbon-1 is above the ring?
Beta
What are two (optical) isomers of glucose, and have different properties?
Galactose and mannose
What is chitin made of and what type of bonds?
N-acetylglucosamine that also form hydrogen bonds
Phosphatidylcholine
Phospholipids undergo dehydration synthesis to join fatty acids, glycerol and polar head group
Are phospholipids amphiphillic molecules?
Yes
What does a trans isomer look like?
across
hydrolysis
adds water to break a molecule apart
Nitrogenous bases are classified as either purines or pyrimidines. Examples of purines are __________.
adenine and guanine
What does a cis isomer look like?
adjacent
What type of molecule can interact with oils and water molecules
amphilic molecules
Phospholipids are ___________ molecules
amphillic
What are lipids?
are fats, phospholipids and steroids that mix poorly with water
What is a phophoanhydride bond?
bond between the phosphates in the ATP
Sugars have a(n) __________ group that interacts with a _________ group that forms ring structures when the dry molecule is placed in water.
carbonyl (-C=O); hydroxyl (-OH)
The molecule with four fused rings that is found in animal membranes and is the precursor of vertebrate sex hormones is __________.
cholesterol
What builds sex hormones?
cholesterol
what is in bile?
cholesterol, Deoxycholic acid, taurocholic acid, phospholipid
How are monosaccharides joined?
covalent bonds
What do steroids do for our cells?
give structure
One characteristic shared by sucrose, lactose, and maltose is that __________.
they are all disaccharides
What is a three fatty acid tails attached to a hydroxyl of glycerol called?
triglyceride
Name two monosaccharides?
Aldose and Ketose
hydroxyl group of carbon-1 is below the plane of ring
Alpha
alpha beta glucose
Alpha: hydroxyl group of carbon-1 is below the plane of ring Beta: hydroxyl group of carbon-1 is above the ring
What other polysaccharide is similar to cellulose?
Chitin
At a conference, the speaker's grand finale was sautéing mealworms (insect larvae) in butter and serving them to the audience. They were crunchy (like popcorn hulls) because their exoskeletons contain the polysaccharide __________.
Chititn
What makes hormones?
Cholesterol
A shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture __________.
DNA
What joins fatty acids to glycerol?
Dehydration synthesis
The sex hormones estrogen, progesterone, and testosterone belong to which class of molecules?
Lipids
Starch has what type of linkage of glucose?
a 1-4
Sugars are molecules that have __________ C:H:O and are called __________.
a 1:2:1 ratio of; carbohydrates
Dehydration synthesis
a chemical reaction in which two molecules become covalently bonded to each other with the removal of water
The peptide bond is __________.
a covalent bond joining amino acids together to form a polypeptide
The components of nucleic acids are __________.
a nitrogenous base, a pentose sugar, and a phosphate
What does amphiphiliic mean?
a term describing a chemical compound possessing both hydrophillic (water-loving, polar) and hydrophobic (water -hating) properties.
alpha beta glucose are in equilibrium in aqueous solutions at a ration of __________
a:B 36:64
What is the most important and common steroid?
cholesteral
When comparing saturated and naturally occurring unsaturated fats, the unsaturated fats have __________ and are __________ at room temperature.
cis double bonds; liquids
The type of bond that forms to join monomers (such as sugars and amino acids) into polymers (such as starch and proteins) is a(n) __________ bond.
covalent
What do trans fats do to HDL (good cholesterol)?
decrease
How are fatty acids joined to glycerol?
dehydration synthesis
In living organisms, DNA exists as a __________ with the strand(s) __________.
double helix; running antiparallel
True or false, Monosaccharides usually exist in linear form?
false
In fats what does the double bond to carbons cause the fat to do?
kink, and make it a liquid because they can't stack on top of each other
where is bile found?
liver
What is the monomer of carbohydrate?
monosaccharides
nucleotides have?
nitrogenous base, 5-carbon sugar (ribose or deoxyribose) phosphate group
Are fats polymers?
no
Can humans break down B 1-4 bonds found in cellulose?
no only bacteria and other microorganisms can
Can we break down molecules in their polymerized form?
no, we can't break them down
is cholesterol nonpolar or polar
nonpolar-because it doesn't interact with water, classifying it as a lipid
Nucleic acids are polymers of what?
nucleotide
Galactose an mannose are what type of isomers of glucose?
optical
What are bacteria cell walls composed of?
peptidoglycan
polymer of amino acids?
polypeptides
How do phospholipids and triglycerides differ?
they differ from triglyceride by polar head and usually have at least on unsaturated carbon
Fats are made up of what?
three fatty acids linked to one glycerol molecule; called triglyceride
In a dehydration synthesis reaction, __________ is always formed as a by-product of the reaction.
water
__________ is always involved in hydrolysis reactions.
water
Why would a phospholipid have one unsaturated fatty acid
you wouldn't want you membranes of cells to be solid immovable structure, you would want it to be able to move
What is carbon used for?
emulsifier gets thing to dissolve well its found in bile
Carbohydrates are used in our bodies mainly for __________.
energy storage and release
"polymer "fatty acids" (lipids are do not have monomers or polymers)
fats and lipids
Lipids are composed of what three molecules part?
fats,membrane lipids, steroids
Phospholipids are composed of three molecule parts?
fatty acids, glycerol, polar group
What does cholesterol do for cell membranes?
give structure
Name monosacchrides
glucose, frutose, glactose, ribose, dioxyribose
A polysaccharide that is used for storing energy in human muscle and liver cells is __________.
glycogen
How are monosaccharides are joined together?
glycosidc linkage by dehydration synthesis
What joins disaccharides together?
glycosidic bond
How are disaccharides joined?
glycosidic bonds
The subunits (monomers) in cellulose are linked together by __________.
glycosidic linkages
Cellulose is strengthened by what type of bonds amoung parallel strands?
hydrogen bonds
Which is the term for compounds that do not mix with water?
hydrophobic
What do trans fats do to LDL (bad cholesterol)?
increase
What is peptidoglycan?
is similar to chitin, but includes alternating N-acetyl-murmaic acids subunits that are covalenty crosslinked
Why does starch use a repeating a1-4 linkage of glucose?
it is created exclusively by plants and used as form of energy storage
The lipids that form the main structural component of cell membranes are __________.
phospholipids
what are most membranes made up of?
phospholipids
where do carbohydrates come from?
photosynthesis, carbon dioxide and water put togeather
What are the polymer of carbohydrates?
polysaccharides
polymer of sugar?
polysaccharides
What causes carbohydrates to form into a ring?
putting them in water
if fat is saturated should it be liquid or solid?
solid
name polysacchrides
starch, cellulose, chitin, glycogen
What do fats do?
storage of energy and insulation protection
name disacchrides
sucrose, maltose, lactose
What hormones does Cholesterol create?
testosterone, estrogen, cortisone, petosterone
