Exam 1 pt 2 Flashcards
(25 cards)
1
Q
- Compare dehydration synthesis and hydrolysis
A
- DS= removing a molecule of water to create a larger molecule
- Hydrolysis= adding a molecule of water to break apart a larger molecule
2
Q
- Describe the function and structure of ATP
A
- Adenosine triphosphate- (nitrogenous base adenine = 5 C sugar ribose)= nucleoside + 3 phosphates
- Stores energy, energy currency molecule
3
Q
What happens when an enzyme is denatured? How does this affect enzyme function?
A
- Cannot function because proteins jobs are dependent on their shape
- Heat and extreme pH causes the breaking of hydrogen bonds and Van Der Waals forces and losing its shape
4
Q
- Compare saturated and unsaturated fats and explain how each would affect membrane fluidity
A
- saturated= has maximum number of Hydrogen it can have
- unsaturated= contains at least one C=C (carbon-carbon double bond)
- unsaturated= more fluid, saturated= less fluid
5
Q
- Compare the terms: magnification, resolution, and contrast
A
- magnification= ratio of object size to image size
- resolution= clarity, the minimum distance that two objects can be distinguished and separate
- contrast= the difference between the light and dark areas in the image
6
Q
- Plasma membrane drawing and difference between hydrophobic and hydrophilic parts
A
hydrophobic tails: water-fearing
hydrophilic heads: water-loving
7
Q
- Why are enzymes so specific as to the reactions they catalyze?
A
- Substrate fits into active site
8
Q
- How does SA/VOL ratio affect cell size?
A
- SA= amount of outer covering
- VOL= how much space it takes up
- Volume increases much more rapidly than surface area and cells cannot feed themselves adequately if they’re too large
9
Q
- What is the function of; ribosomes, lysosomes, centrioles, mitochondria, cytoskeleton, and vacuoles
A
- ribosomes= protein synthesis
- lysosomes= suicide sac with hydrolytic enzymes to break large molecules into smaller ones
- centrioles= organize microtubules that serve as the cellular skeletal system
- mitochondria= generates ATP, cellular respiration
- cytoskeleton= helps cells maintain shape and internal organization
- vacuoles= holds food for later use or holds waste to get rid of
10
Q
- Compare desmosomes, tight junctions, and gap junctions
A
- Desmosomes: anchoring junctions, rivets that help adjacent cells connect to each other
- Tight junctions: prevent leakage between cells, make things watertight
- Gap junctions: cytoplasmic channels that connect one cell to the next created by membrane proteins
11
Q
- What is the fluid mosaic model?
A
- Describing the plasma membrane as being fluid, mosaic of the different components of the plasma membrane
12
Q
- Compare simple and facilitated diffusion
A
- Both with the concentration gradient, passive (no energy required)
- Facilitated: requires a highly specific carrier protein, rate of diffusion is unchanged regardless of solute concentration (reaches a plateau) due to number of specialty carrier proteins
13
Q
- Define paracrine, synaptic, and endocrine signaling
A
- Paracrine: local, signaling between nearby cells
- Synaptic: neurotransmitters moving between the space between nerve cells, specific to nerve cells
- Endocrine: hormones, certain receptors in target cells
14
Q
- Draw hypotonic, hypertonic, and isotonic environments
A
*hypotonic: lower concentration of solute in environment
*hypertonic: higher concentration of solute in environment
*isotonic: equal concentration of solute inside and out of the cell
15
Q
- What is a phosphorylation cascade? How is it advantageous?
A
- A phosphorylation cascade occurs when a signal molecule initiates a cascade where a kinase (transfer phosphate groups) transfers a phosphate to an enzyme that then transfers another phosphate etc.
- Advantage: to magnify the single signal, activation of multiple enzymes with one signal for a larger cellular response
16
Q
- Describe how a GPCR (gene protein coupled receptor) works
A
- On exterior of plasma membrane, does not dissolve. GTP not ATP, enzyme activation
17
Q
- How does a H+ ion concentration change going from pH 6 to 4?
A
- The H+ ion concentration is increasing (100x more H+ ions)
18
Q
- How does high and low pH affect enzyme function? Why?
A
- Low pH: not very active
- High pH: not very active
- Looks like a bell curve
- H+ bonds break in extreme pH environments so they become denatured
19
Q
- Give two specific examples of active transport
A
- Proton pump (plants)- H+ ions
- Sodium-potassium pump (animals) (LOH)
20
Q
- List some unique properties of water. What do they all have in common?
A
- High specific heat (amount of thermal energy a substance can absorb before changing temperature), H+ bonds absorb a lot more energy before breaking
- Cohesive behavior (sticks to itself)
- Adhesion (sticks to other molecules through H+ bonds)
- Ice buoyancy (less dense due to max number of H+ bonds), max density of water is 4C
- Heat of vaporization (how animals cool themselves)
- Versatile solvent
- All in common: H+ bonds and a polar molecule
21
Q
- Compare alpha glucose and beta glucose
A
- Alpha: below ring in 1st carbon, starch
- Beta: above ring in 1st carbon, cellulose
22
Q
- Compare kinases and phosphatases
A
- Kinase: add phosphates
- Phosphatase: remove phosphates
23
Q
- Compare dehydration synthesis and hydrolysis reactions
A
- DS: removing a molecule of water to join two molecules together
- HR: adding a molecule of water to break apart two molecules
24
Q
- Give an example of a channel protein
A
- Aquaporen: pore created by proteins that allows water to pass through into the cell
25
* What is the sequence of steps when a GPCR is activated?
* DNA->RNA->protein
