Exam 2

Question 1

Monomer

Answer 1

->molecule, that if bonded together forms a polymer
-> smaller molecules together, often using repeating units of the same kind of molecule

Question 2

Polymer

Answer 2

->Biological macromolecules are made by assembling monomers together
-> these macromolecules together are called polymers
-> polymers create something new

Question 3

Dehydration synthesis

Answer 3

putting little things together to make big polymers
-> removes a water molecule (H2O)
(water is a product)
when dehydrated you don’t have a lot of water so dehydration synthesis removes H2O

Question 4

Hydrolysis

Answer 4

breaks down a polymer
-> adds a water molecule, which breaks down a bond
Ex. eating snickers bar and digesting it
(water is a reactant)

Question 5

4 Types of Biological Macromolecules

Answer 5

carbohydrates, nucleic acids, lipids, proteins

Question 6

Carbohydrates

Answer 6

Carbohydrates are sugar-based molecules
-> Single sugar monomers are connected by glycosidic linkages (using dehydration synthesis) to make disaccharides or polysaccharides

Question 7

alpha glycosidic linkages

Answer 7

starch in plants or glycogen in animals are large polysaccharides with many branches used to store glucose for energy. These are connected by alpha glycosidic linkages that are digestible by eukaryotes.
Alpha=big strong energy!!

Question 8

beta glycosidic linkages

Answer 8

Cellulose is polysaccharide made by glucose molecules connected with beta glycosidic linkages that are not digestible by eukaryotes, and are used for structural support in plant cell walls.
b=bad
bad for eukaryotes to digest
CELLulose=CELL walls

Question 9

Nucleic acids

Answer 9

made by combining nucleotides (monomers) together using phosphodiester bonds (by dehydration synthesis) to make polynucleotides including DNA and RNA.

Question 10

3 Parts of Nucleotides

Answer 10

Base, Sugar, Phosphate

Question 11

Lipids

Answer 11

hydrophobic molecules, including the triglycerides, phospholipids, and steroids

Question 12

Triglycerides

Answer 12

consist of three fatty acids attached to a glycerol molecule (dehydration synthesis again). and can be solid (fats) or liquid (oils) at room temperature.

Question 13

Saturated fatty acids

Answer 13

lack double bonds and form straight molecules that can pack closely together so they are solid at room temperature (fats)

Question 14

Unsaturated fatty acids

Answer 14

have one or more double bonds and are bent, so they push each other further apart making them fluid (oils).

Question 15

Phospholipids

Answer 15

have a glycerol with two very hydrophobic fatty acid “tails” and one very hydrophilic phosphocholine “head.” The balance between these components is just right, making phospholipids amphipathic. Groups of phospholipids can be arranged in a bilayer in water.

Question 16

Steroids

Answer 16

not macromolecules but they are hydrophobic. An important steroid for membrane structure-function relationships is cholesterol.

Question 17

Cholesterol

Answer 17

moderates fluidity
-> makes fluid membrane more viscous
->makes viscous membrane more fluid

Question 18

Proteins

Answer 18

very large polymers made by connecting amino acids (monomers) together with peptide bonds to make polypeptides.
The function of a protein is dependent on its shape.

Question 19

Primary Structure of Protein

Answer 19

the sequence of amino acids
There are 20 naturally occurring amino acids, each with a different “R-group”
->different properties such as hydrophilic, hydrophobic, charged, polar, acidic, or basic

Question 20

Secondary Structure of a Protein

Answer 20

->repeated folding of protein backbone
2 ways:
-> folds sections of polypeptide into beta sheets
->coils into alpha helices

Question 21

Tertiary Structure of a Protein

Answer 21

->folding a single polypeptide into complex 3D shape. ->Having the correct shape is key to proper protein function.

Question 22

Quaternary Structure

Answer 22

->multiple 3D polypeptide shapes put together to form large one
->forms larger protein molecules

Question 23

How do Proteins change shape?

Answer 23

Proteins are able to change shape under different conditions because they are largely held together by weak interactions such as hydrogen bonds and ionic bonds.

Question 24

Ligand

Answer 24

signal molecule that binds to larger molecules receptors

Question 25

Cell communication

Answer 25

Reception: ligand binds to a receptor protein, causing a change in the shape of the protein.
Signaling: proteins inside the cell recognize the change in shape of a receptor bound by ligand and trigger a signal transduction cascade. Cells determine what proteins are in the signal transduction cascade to ensure appropriate response to a signal.
Response: create a diversity of responses among cells

Question 26

Receptor tyrosine kinases

Answer 26

->transmembrane receptors that have the ligand binding part outside the cell and an enzyme part inside the cell on a single protein.
->RTKs dimerize, causing autophosphorylation, which activates the kinase enzyme function and triggers a signal transduction cascade.

Question 27

G-protein coupled receptors

Answer 27

transmembrane receptors that have separate proteins for ligand binding and enzymatic response. These proteins are “coupled” by a G-protein that becomes activate on ligand binding by the receptor and in turns activates an enzyme that triggers a signal transduction cascade.

Question 28

Gated ion channels

Answer 28

normally closed but will open and allow facilitated diffusion when bound by a signaling molecule.

Question 29

Phagocytosis

Answer 29

creates large vesicles and can bring in large amounts of material

Question 30

Pinocytosis

Answer 30

creates small vesicles that are used to transport water

Question 31

Receptor mediated endocytosis

Answer 31

uses transmembrane receptor proteins to selectively bring in large amounts of the same solute very specifically.

Question 32

How to recognize Active transport?

Answer 32

-directly from chemical energy in ATP
-from high-energy electrons
-from energy in a gradient of another solute

Question 33

Channel Proteins

Answer 33

create aqueous pathways for the diffusion of ions

Question 34

Carrier Proteins

Answer 34

move larger molecules across the membrane by changing shape

Question 35

Coupled Transport

Answer 35

Symport: move more than one solute at a time in the same direction
Antiport: move more than one solute at a time in different directions