Unit 3 Flashcards
What are molecules called if the contain carbon?
Organic
How many bonds can a carbon atom form?
4
monomers
simple organic molecules
polymers
made of monomers arranged in a simple repeating structure
macromolecules
large, complex molecules made from thousands of atoms (does not have to be a polymer)
condensation reaction
link monomers to form polymers
In a condensation reaction is water added or removed?
One water molecule removed
hydrolysis reactions
break down polymers into smaller molecules
In a hydrolysis reaction is water added or removed?
One water molecule is added
What are the 4 classes of macromolecules in living things?
- Carbohydrates
- Lipids
- Proteins
- Nucleic Acids
What do carbohydrates contain?
contain carbon, hydrogen, and oxygen atoms
What are 3 important things to know about carbohydrates?
- Energy source/storage
- Structural molecules that give cells shape
- Recognition or signaling molecules
Monosaccharides
carbohydrate monomers
What are some characteristics of monosaccharides?
- most end in -ose
- typically have a formula that’s a multiple of CH2O.
What are two things monosaccharides can be used for?
fuel and combining polymers
Pentoses
5-carbon sugars
What are 2 examples of pentoses and where are they found?
- ribose, found in RNA
- deoxyribose, found in DNA
Hexose
6-carbon sugars
What is an example of a hexose?
glucose
Glucose
used as a source of energy by the cell
How is glucose made?
by photosynthesis
What does glucose start?
cellular respiration
What do monosaccharides do in aqueous solutions?
Form rings
Planar
flat
What is the structure of sugar rings?
It has -H and -OH groups above and below the plane of the ring
Isomers
compounds with the same formula but a different arrangement of atoms
What makes a glucose isomer alpha-D-Glucose (trans configuration)?
When the carbon 1 -OH and CH2OH are on OPPOSITE sides
What makes a glucose isomer beta-D-Glucose (cis configuration)?
When the carbon 1 -OH and CH2OH on the SAME side
Disaccharides
Consist of two monosaccharides
Glycosidic Linkages
The covalent bonds joining monosaccharides
Maltose (2 characteristics)
- The bonding of two glucose units
- glycosidic linkage at α-(1,4)
What two monosaccharides are needed to make maltose?
glucose + glucose
What two monosaccharides are needed to make sucrose?
glucose + fructose
What two monosaccharides are needed to make lactose?
glucose + galactose
Polysaccharides
carbohydrates made from long chains of monosaccharides (hundreds)
What can polysaccharides be (2)?
- storage molecules
- structural compounds
Starch (2 things to know)
major storage form of energy/glucose in plants
polymer made from alpha-glucose monomers
What 2 things does starch contain?
amylose and amylopectin
Amylose (3 thing to know)
- made from α-glucose monomers
- linked by α-(1,4) glycosidic linkages
- wound into coils stabilized by hydrogen bonds
Amylopectin
α-glucose joined by α-(1,4) and α–(1,6) glycosidic linkages
What do α–(1,6) glycosidic linkages do?
form branches
What is the structure and function of amylose (3)?
- helical in structure
- tightly packed
- good for storage
What is the structure and function of amylopectin (3)?
- branched
- takes up more space
- easier to digest
What is amylopectin used for?
making adhesives and lubricants
Where are starches found?
plants
Where is glycogen found?
animals
What are the two types of storage polysaccharides?
starches and glycogen
Glycogen (4 things you need to know)
- major storage form of glucose (energy) in animals
- polymer made from alpha-glucose monomers
- joined by α-(1,4) and α-(1,6) linkages
- has more branches than amylopectin in starch
Where can glycogen be found?
muscle and liver
What does the liver store glucose as?
glycogen
How does the liver provide sugar/glucose?
it turns glycogen into glucose
What is a structural polysaccharide?
cellulose
Cellulose (3 things you need to know)
- the most abundant natural polymer
- the strength and support in plant cell walls
- a polymer made from beta-glucose monomers
How do you form a bond between two molecules of beta-glucose?
each β-glucose molecule is rotated 180° compared to the one next to it
What is the structure of a polysaccharide (3)?
- has straight, unbranched chains that run parallel
- has hydrogen bonds linking cellulose chains to provide strength
- provides rigidity to cell walls to prevent cells from bursting when full with water
Lipids (4 things you need to know)
- contain nonpolar hydrocarbons
- are insoluble in water due to nonpolar hydrocarbons.
- are grouped together because
they are hydrophobic - are not true polymers
What are the functions of lipids (2)?
-energy source
-energy storage
How is the energy in carbohydrates described?
readily available/quick energy
How is the energy in lipids described?
available at a slower pace
What is an important comparison between lipids and glycogen?
Lipids contain more energy per gram than glycogen
What are the 3 types of lipids?
fatty acids, phospholipids, and triglycerides
What is the structure of a fatty acid?
carboxylic acid group (COOH) with a hydrocarbon chain attached
What are some characteristics of fatty acids?
- Fatty acids can vary in length due to the # carbons in the hydrocarbon tail
- Fatty acids are insoluble
Why are fatty acids insoluble?
due to the nonpolar hydrocarbon tail
How can fatty acids be classified?
whether or not they have double bonds
Saturated fatty acids
only single bonds in the hydrocarbon tail
Unsaturated fatty acids
one or more double bonds in the hydrocarbon tail
What can unsaturated fatty acids be?
monounsaturated or polyunsaturated
Monounsaturated fatty acids
one double bond in the fatty acid tail
Polyunsaturated fatty acids
two or more double bonds in the fatty acid tail
What types of isomers can unsaturated fatty acids be?
cis or trans
Cis isomer
hydrogens on same side of double bond (fatty acid tails have kinks)
Trans isomer
hydrogens on opposite side of double bond
What do phospholipids consist of (3)?
- Two fatty acids
- One glycerol
- One phosphate group
What is the function of a phospholipid?
Major component in cell membranes- lipid bilayer
What does a triglyceride consist of?
three fatty acids and one glycerol
What is the main function of a triglyceride?
energy storage
What are two things triglycerides can be at room temperature?
fats (solid) or oils (liquid)
What types of fatty acids are fats made up of?
saturated and trans-unsaturated fatty acids
What what types of fatty acids are oils made up of?
cis-unsaturated fatty acids
Which fats occur naturally in foods
saturated and cis-unsaturated fats
Where are saturated fats found?
in animal sources such as meat and dairy
Where are cis-unsaturated fats found?
in plant sources such as nuts, oils, fish, and vegetables
How are trans-unsaturated fats made?
they are man made
Which fats have negative health effects?
saturated and trans-unsaturated fats
Which fats have positive health effects?
cis-unsaturated fats
What do trans-unsaturated and saturated fats increase the risk of?
coronary heart disease (CHD)
What can the high energy content of lipids contribute to (4)?
- (CHD)
- stroke
- high blood pressure
- type 2 diabetes
Body Mass Index (BMI)
indicator of body fatness
nomogram
tool used to find BMI
What do steroids have?
four nonpolar fused rings
Cholesterol
a steroid that contributes to the production of hormones, vitamin D, bile, and cell membrane support
What kinds of effects does cholesterol have on health?
- synthesized in the liver & obtained from animal products
- factors other than diet can affect cholesterol levels (genetic factors)
- lowering its ingestion may lower the risk of CHD in some individuals
- Can cause CHD if it builds up in the walls of arteries & causes clogging/ atherosclerosis;
Proteins
most structurally and functionally diverse of life’s molecules
What are the monomers of proteins?
amino acids
What are the components of an amino acids?
- Central Carbon
- Amine Group
- Carboxyl Group
- Hydrogen Group
What is important about R groups?
it distinguishes each of the different amino acids
How many amino acids to living things use?
20
What type of reaction forms polypeptide bonds?
condensation reactions
What determines a protein’s function?
its shape
Primary structure
The unique sequence of amino acids in a polypeptide
What codes the sequence of polypeptides?
genes in the DNA
Genes
sequence of DNA that programs an amino acid sequence and controls a characteristic of an organism
Secondary Structure
The folding or coiling of the polypeptide into a repeating configuration
What types of configuration come out of secondary structure?
α helix and β pleated sheet
What stabilizes secondary structures?
hydrogen bonds
Where to hydrogen bonds form in secondary structures?
between amine and carboxyl groups
Tertiary Structure
the overall 3-D shape of a polypeptide
How are tertiary and quaternary structures stabilized?
by interactions between R groups
What types of bonds stabilize tertiary and quaternary structures (4)?
- hydrogen bonding
- ionic interactions
- hydrophobic interactions
- disulfide bridges
How do amino acids with nonpolar R groups fold?
they cluster in the interior of the protein (away from water)
How do amino acids with polar R groups fold?
they cluster on the surface (interact with water)
What is the position of proteins that contain amino acids with nonpolar R groups in the phospholipid bilayer?
they are embedded in the nonpolar interior
What is the position of proteins that contain amino acids with polar R groups in the phospholipid bilayer?
they protrude from the membrane and form the pore
What determines tertiary structure?
primary structure determines tertiary structure
Quaternary Structure
the overall protein structure that results from the aggregation of two or more polypeptide subunits
What can disrupt secondary, tertiary, and quaternary structure?
high temperatures or varying pH levels
What does high temperature and varying temperature not effect primary structure?
covalent bonds remain undisturbed
Denaturing
structural change in a protein that results in the loss of its biological properties
What are the two types of protein shapes?
globular and fibrous
Globular
overall spherical shape; mostly water soluble; can be enzymes, transport proteins, hormones
What is an example of a globular protein?
hemoglobin
Fibrous
long fiber shape; insoluble in water; structural/movement functions
What is an example of a fibrous protein?
collagen
What are 2 protein functions?
Hormones and Sensation
What is an example of the protein function of ‘hormones’?
Insulin signals glucose uptake by cells
What is an example of the protein function of ‘sensation’?
Rhodopsin detects light in the retina of the eye
