UW Madison Bio 101 Exam 1 Latest 2023 with complete
solution
What is a covalent bond?
When two atoms share electrons
What are the three key polar covalent bonds (for the sake of this class)?
O-H, N-H, S-H
What can H bond to?
Other polar molecules and water.
How are polymers built?
Through dehydration reactions (Monomer in, water out)
How are polymers broken down?
Through hydrolysis reactions (Water in, monomer out)
What is the identifying shape of a carbohydrate?
Ring-shaped
What is the function of a disaccharide?
To be broken down for quick energy.
What is the function of glucose?
Glucose is a monosaccharide that is used as fuel to make ATP.
T/F: All polysaccharides are composed of glucose.
True
What is the function of a starch? Where is it found?
Function: Energy Storage
Found: in plants
What is the function of glycogen? Where is it found?
Function: energy storage
Found: animals
What is the function of cellulose? Where is it found?
Function: Structural
Found: Plant cells
What is the function of chitin? Where is it found?
Function: Structural
Found: Insects, some animals, fungi
Can animals break down cellulose?
No. Cows can only break down cellulose because of microorganisms within their
stomach that can.
Describe what a protein structure looks like?
A central carbon is bonded to an amino group, a hydrogen, a carboxyl group, and a
varying R group.
Which end of a polypeptide is read first; the carboxyl terminus or amino terminus?
The amino terminus
What must happen to a polypeptide before it can become a functioning protein?
It must fold.
What is the first level (degree) of protein structure?
It is the linked series of amino acids and their unique sequence.
, What is the second level (degree) of protein structure?
Alpha helices or beta-pleated sheets. Localized folding created by H bonding
What is the third level (degree) of protein structure?
The 3D shape of a protein due to the interactions between R groups.
What types of interactions between R groups are important in maintaining tertiary
structure? Describe them.
1.Hydrogen bonds
2. Disulfide bridge (covalent bond)
3. Ionic bonds (attraction between (+) and (-) charges)
4. Hydrophobic exclusion (interactions [many hydrophobic parts moving toward inside])
What do chaperone proteins do?
They stop improper actions from occurring while the proteins are being folded.
What is the fourth level (degree) of protein structure?
The aggregation of two or more polypeptides.
Will a change in primary structure result in problems downstream in structure or
functioning of a protein?
Not always. It just depends on what the change is and where.
Are enzymes functional at non-optimal conditions?
No. Physical conditions effect enzyme function
What are the functions of lipids?
Growth, utilization of some vitamins, insulation, hormones, excellent energy source, and
a major component of cell membranes.
What are the functions of steroids?
Hormones (estrogen and testosterone) and membrane structure (cholesterol)
How does cholesterol move through the bloodstream?
As a lipoprotein complex
Describe low density lipoprotein and high density lipoprotein.
LDL- carries cholesterol from the liver to cells. "bad" cholesterol. can clog arteries.
HDL- picks up excess cholesterol from cells. Delivers to the liver for recycling/disposal.
"Good" cholesterol. cleans up after LDLs
What is the function of fats and oils? Are they hydrophilic or hydrophobic?
The main function is energy storage. They are VERY hydrophobic.
What are the differences between saturated fats and unsaturated fats?
Saturated- there are no C=C. Straight shape. They increase the level of HDL and LDL in
the body (net (-) effect)
Unsaturated- there is at least one C=C. There are kinks in the shape of it. They
decrease LDLs and raise HDLs
What is the function of phospholipids?
Membrane structure
What does a phospholipid structure look like?
There are two fatty acid tails and a phosphate containing head group. It has
amphipathic, hydrophobic, and hydrophilic regions
What do phospholipids do in water?
micelles form (droplets). Hydrophilic heads around the outside, hydrophobic tails in the
inside.
What is the function of the plasma membrane?
solution
What is a covalent bond?
When two atoms share electrons
What are the three key polar covalent bonds (for the sake of this class)?
O-H, N-H, S-H
What can H bond to?
Other polar molecules and water.
How are polymers built?
Through dehydration reactions (Monomer in, water out)
How are polymers broken down?
Through hydrolysis reactions (Water in, monomer out)
What is the identifying shape of a carbohydrate?
Ring-shaped
What is the function of a disaccharide?
To be broken down for quick energy.
What is the function of glucose?
Glucose is a monosaccharide that is used as fuel to make ATP.
T/F: All polysaccharides are composed of glucose.
True
What is the function of a starch? Where is it found?
Function: Energy Storage
Found: in plants
What is the function of glycogen? Where is it found?
Function: energy storage
Found: animals
What is the function of cellulose? Where is it found?
Function: Structural
Found: Plant cells
What is the function of chitin? Where is it found?
Function: Structural
Found: Insects, some animals, fungi
Can animals break down cellulose?
No. Cows can only break down cellulose because of microorganisms within their
stomach that can.
Describe what a protein structure looks like?
A central carbon is bonded to an amino group, a hydrogen, a carboxyl group, and a
varying R group.
Which end of a polypeptide is read first; the carboxyl terminus or amino terminus?
The amino terminus
What must happen to a polypeptide before it can become a functioning protein?
It must fold.
What is the first level (degree) of protein structure?
It is the linked series of amino acids and their unique sequence.
, What is the second level (degree) of protein structure?
Alpha helices or beta-pleated sheets. Localized folding created by H bonding
What is the third level (degree) of protein structure?
The 3D shape of a protein due to the interactions between R groups.
What types of interactions between R groups are important in maintaining tertiary
structure? Describe them.
1.Hydrogen bonds
2. Disulfide bridge (covalent bond)
3. Ionic bonds (attraction between (+) and (-) charges)
4. Hydrophobic exclusion (interactions [many hydrophobic parts moving toward inside])
What do chaperone proteins do?
They stop improper actions from occurring while the proteins are being folded.
What is the fourth level (degree) of protein structure?
The aggregation of two or more polypeptides.
Will a change in primary structure result in problems downstream in structure or
functioning of a protein?
Not always. It just depends on what the change is and where.
Are enzymes functional at non-optimal conditions?
No. Physical conditions effect enzyme function
What are the functions of lipids?
Growth, utilization of some vitamins, insulation, hormones, excellent energy source, and
a major component of cell membranes.
What are the functions of steroids?
Hormones (estrogen and testosterone) and membrane structure (cholesterol)
How does cholesterol move through the bloodstream?
As a lipoprotein complex
Describe low density lipoprotein and high density lipoprotein.
LDL- carries cholesterol from the liver to cells. "bad" cholesterol. can clog arteries.
HDL- picks up excess cholesterol from cells. Delivers to the liver for recycling/disposal.
"Good" cholesterol. cleans up after LDLs
What is the function of fats and oils? Are they hydrophilic or hydrophobic?
The main function is energy storage. They are VERY hydrophobic.
What are the differences between saturated fats and unsaturated fats?
Saturated- there are no C=C. Straight shape. They increase the level of HDL and LDL in
the body (net (-) effect)
Unsaturated- there is at least one C=C. There are kinks in the shape of it. They
decrease LDLs and raise HDLs
What is the function of phospholipids?
Membrane structure
What does a phospholipid structure look like?
There are two fatty acid tails and a phosphate containing head group. It has
amphipathic, hydrophobic, and hydrophilic regions
What do phospholipids do in water?
micelles form (droplets). Hydrophilic heads around the outside, hydrophobic tails in the
inside.
What is the function of the plasma membrane?
