Biology & Biochemistry

Question 1

Prosthetic Group

Answer 1

a nonprotein group forming part of or combined with a protein (e.g., Heme)

Question 2

Holoenzyme

Answer 2

an apoenzyme together with its cofactor – a holoenzyme is complete and catalytically active.

“that’s a holla-enzyme”

Question 3

Chaperones

Answer 3

a protein that assists the conformational folding or unfolding and the assembly or disassembly of other macromolecular structures

Question 4

Cofactors

Answer 4

a non-protein chemical compound or metallic ion that is required for an enzyme’s activity as a catalyst

Question 5

Nonsense Mutation

Answer 5

a mutation that causes the premature truncation of a protein, often leaving it ENTIRELY DYSFUNCTIONAL

Question 6

Missense Mutation

Answer 6

protein is translated and transcribed in a normal fashion, with some changes to amino acid sequence

Question 7

Frameshift Mutation

Answer 7

a mutation that causes significant disruption and renders the protein dysfunctional

Question 8

Silent Mutation

Answer 8

no alteration in protein activity

Question 9

Km

Answer 9

1/2 * Vmax, a rough estimate of binding affinity, a measure for how well an enzyme binds its substrate

an increase in Km means lower affinity

Question 10

Competitive Inhibition

Answer 10

Km: Increased
Vmax: No Change

Question 11

Uncompetitive Inhibition

Answer 11

Km: Decreased
Vmax: Decreased

Question 12

Noncompetitive Inhibition

Answer 12

Km: No Change
Vmax: Decreased

Question 13

Epithelial Cells

Answer 13

Epithelial cells are cells that come from surfaces of your body, such as your skin, blood vessels, urinary tract, or organs. They serve as a barrier between the inside and outside of your body, and protect it from viruses. A small number of epithelial cells in your urine is normal.

Question 14

Endoderm

Answer 14

The innermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the lining of the gut and associated structures.

Question 15

G1

Answer 15

“The first gap phase”

• cells grow larger
• copies are made of organelles
• prepare for later steps

Question 16

G2

Answer 16

“Gap phase two”

• cells make more proteins + organelles
• organize cell content

Question 17

S

Answer 17

“Synthesize”

• complete DNA copies are made
• duplicate centrosomes, which help with DNA separation

Question 18

Mitosis

Answer 18

• DNA forms chromosomes
• Pulled apart by mitotic spindle
• Composed of prophase, metophase, anaphase, and telophase

Question 19

Cytokinesis

Answer 19

• cytoplasm split into two

- different between plants & animals

Question 20

G0

Answer 20

rest phase

Question 21

Desmosomes

Answer 21

a structure by which two adjacent cells are attached, formed from protein plaques in the cell membranes linked by filaments

Question 22

Gap junctions

Answer 22

protein channels that permit the flow of small ions from cell to cell – they are abundant in the heart, where proper ion flow is necessary for coordinated contraction

Question 23

Plasmodestata

Answer 23

a narrow thread of cytoplasm that passes through the cell walls of adjacent plant cells and allows communication between them

Question 24

Tight junctions

Answer 24

At the site of a tight junction, cells are held tightly against each other by many individual groups of tight junction proteins called claudins, each of which interacts with a partner group on the opposite cell membrane. The groups are arranged into strands that form a branching network, with larger numbers of strands making for a tighter seal.

The purpose of tight junctions is to keep liquid from escaping between cells, allowing a layer of cells (for instance, those lining an organ) to act as an impermeable barrier.