UCI Bio 93 Final Exam Questions and Answers |Complete Solutions Graded A+ |100% Correct
What happens in elongation in translation? The next tRNA, carrying the next amino acid to
be added to the polypeptide chain, enters the A site of the complex. A peptide bond is formed
between the Amino Acid in the P site and the new Amino Acid in the A site. Then, translocation
occurs, in which the tRNA in the A site moves to the P site, and the tRNA in the P site moves to
the E site. Finally, the tRNA in the E site is ejected and the polypeptide chain is in the P site.
What happens in termination in translation? The ribosome will eventually arrive at a stop
codon on the DNA. There is no tRNA that can bind to this codon. A release factor will enter the
A side, and promote hydrolysis of the polypeptide chain from the tRNA in the P site. The
ribosomal subunits and the other components dissociate. As a result, a free polypeptide chain is
released.
Is a lipid a polymer? No, because they are formed from 2 different types of subunits.
What bonds are formed to turn monosaccharides into carbohydrates? Glycosidic linkages.
What bonds are formed to turn amino acids into proteins? polypeptide bonds.
What bonds are formed to turn nucleotides into nucleic acids? hydrogen bonds.
What are saturated fats? Viscous fats found in animal products (solid at room temperature
ex: butter). They are fatty acids with no CC double bond which mean that they are more closely
packed and therefore harder to digest.
What are unsaturated fats? Fluid fats found in plant based products. They have CC double
bonds which leads to a kink in the structure, thus allowing it to be more fluid leading to easier
digestion.
What do buffers do? Resist change in pH.
,Phospholipids have a ___________ head and a _________ tail. Hydrophilic, Hydrophobic.
This allows for selective permeability when forming the phospholipid bilayer.
What is a eukaryotic cell? An animal, plant, protist, or fungi cell that has a nucleus,
organelles, and linear DNA.
What is a prokaryotic cell? A bacteria or archaea cell that has a nucleoid and circular DNA.
What do eukaryotes and prokaryotes both have? Cells, a cell membrane, and ribosomes.
How are polymers formed? Dehydration -- the removal of a water molecule to allow the
monomers to covalently bond.
How are polymers broken up? Hydrolysis -- the addition of a water molecule to break the
covalent bond between the monomers.
What are purines? Adenine, guanine (2 rings)
What are pyrimidines? Cytosine, thymine, uracil (1 ring)
What is the primary level of protein structure? The polypeptide bonding forming a linear
amino acid sequence.
What is the secondary level of protein structure? The formation of alpha helices and beta
pleated sheets by hydrogen bonds in the backbone.
What is the tertiary level of protein structure? The formation of disulfide bridges between R
groups.
, What is the quaternary level of protein structure? The formation of two or more
polypeptides.
High temperature _________ membrane fluidity. Reduces.
Low temperature ____________ membrane fluidity. Increases.
In a hypotonic solution, a red blood cell will ______. Lyse (swell) due to the intense influx of
water inside the cell. WATER FLOWS WHERE THE MOST SOLUTES ARE.
In a hypertonic solution, a red blood cell will ______. Shrivel, due to the amount of water
inside the cell that wants to escape to balance the solution. WATER FLOWS WHERE THE MOST
SOLUTES ARE.
In an isotonic solution, a red blood cell will ______. Remain the same.
What does endocytosis do? What are some examples of endocytosis? Vesicles brings
external molecules inside the cell. Phagocytosis, pinocytosis, receptor mediated endocytosis.
What does exocytosis do? Vesicles releases molecules outside the cell.
What happens in phagocyotsis? Pseudopodium surround food to generate a food vacuole.
What happens in pinocytosis? A portion of the plasma membrane pinches off to bring in
different molecules (non specific).
What happens in receptor mediated endocytosis? Receptors pick up ligands and then send a
signal to pinch off and create a coated vesicle (specific mechanism). Ex: LDL -- low density
lipoproteins -- LDL binds to receptors on the membrane and causes endocytosis to occur.
What happens in elongation in translation? The next tRNA, carrying the next amino acid to
be added to the polypeptide chain, enters the A site of the complex. A peptide bond is formed
between the Amino Acid in the P site and the new Amino Acid in the A site. Then, translocation
occurs, in which the tRNA in the A site moves to the P site, and the tRNA in the P site moves to
the E site. Finally, the tRNA in the E site is ejected and the polypeptide chain is in the P site.
What happens in termination in translation? The ribosome will eventually arrive at a stop
codon on the DNA. There is no tRNA that can bind to this codon. A release factor will enter the
A side, and promote hydrolysis of the polypeptide chain from the tRNA in the P site. The
ribosomal subunits and the other components dissociate. As a result, a free polypeptide chain is
released.
Is a lipid a polymer? No, because they are formed from 2 different types of subunits.
What bonds are formed to turn monosaccharides into carbohydrates? Glycosidic linkages.
What bonds are formed to turn amino acids into proteins? polypeptide bonds.
What bonds are formed to turn nucleotides into nucleic acids? hydrogen bonds.
What are saturated fats? Viscous fats found in animal products (solid at room temperature
ex: butter). They are fatty acids with no CC double bond which mean that they are more closely
packed and therefore harder to digest.
What are unsaturated fats? Fluid fats found in plant based products. They have CC double
bonds which leads to a kink in the structure, thus allowing it to be more fluid leading to easier
digestion.
What do buffers do? Resist change in pH.
,Phospholipids have a ___________ head and a _________ tail. Hydrophilic, Hydrophobic.
This allows for selective permeability when forming the phospholipid bilayer.
What is a eukaryotic cell? An animal, plant, protist, or fungi cell that has a nucleus,
organelles, and linear DNA.
What is a prokaryotic cell? A bacteria or archaea cell that has a nucleoid and circular DNA.
What do eukaryotes and prokaryotes both have? Cells, a cell membrane, and ribosomes.
How are polymers formed? Dehydration -- the removal of a water molecule to allow the
monomers to covalently bond.
How are polymers broken up? Hydrolysis -- the addition of a water molecule to break the
covalent bond between the monomers.
What are purines? Adenine, guanine (2 rings)
What are pyrimidines? Cytosine, thymine, uracil (1 ring)
What is the primary level of protein structure? The polypeptide bonding forming a linear
amino acid sequence.
What is the secondary level of protein structure? The formation of alpha helices and beta
pleated sheets by hydrogen bonds in the backbone.
What is the tertiary level of protein structure? The formation of disulfide bridges between R
groups.
, What is the quaternary level of protein structure? The formation of two or more
polypeptides.
High temperature _________ membrane fluidity. Reduces.
Low temperature ____________ membrane fluidity. Increases.
In a hypotonic solution, a red blood cell will ______. Lyse (swell) due to the intense influx of
water inside the cell. WATER FLOWS WHERE THE MOST SOLUTES ARE.
In a hypertonic solution, a red blood cell will ______. Shrivel, due to the amount of water
inside the cell that wants to escape to balance the solution. WATER FLOWS WHERE THE MOST
SOLUTES ARE.
In an isotonic solution, a red blood cell will ______. Remain the same.
What does endocytosis do? What are some examples of endocytosis? Vesicles brings
external molecules inside the cell. Phagocytosis, pinocytosis, receptor mediated endocytosis.
What does exocytosis do? Vesicles releases molecules outside the cell.
What happens in phagocyotsis? Pseudopodium surround food to generate a food vacuole.
What happens in pinocytosis? A portion of the plasma membrane pinches off to bring in
different molecules (non specific).
What happens in receptor mediated endocytosis? Receptors pick up ligands and then send a
signal to pinch off and create a coated vesicle (specific mechanism). Ex: LDL -- low density
lipoproteins -- LDL binds to receptors on the membrane and causes endocytosis to occur.
