Exam 2 (Lectures6-9)

Question 1

Membranes have

Answer 1

selective permeability(some substances pass but not all

Question 2

Passive transport. energy or no energy?

Answer 2

no outside energy required

Question 3

Diffusion

Answer 3

process of random movement toward equilibrium from high concentration to low

Question 4

Equilibrium

Answer 4

particles continue to move but there is no net change in distribution

Question 5

permeable;impermeable

Answer 5

can cross easily; cannot cross

Question 6

Simple diffusion

Answer 6

hydrophobic molecules easily pass through the lipid bilayer

Question 7

membrane permeable?
water, sodium, chloride, glucose, amino acid, protein, cholesterol

Answer 7

yes but slow, no cause charge, no cause charged, no is hydrophilic, no cause charge, no, yes cause it is hydrophobic

Question 8

osmosis

Answer 8

diffusion of water across membranes. high water concentration to low water

Question 9

osmosis depends on the

Answer 9

number of solute particles not the type of particles

Question 10

osmosis solution types

Answer 10

isotonic:equal solute concentration
hypertonic solution: higher solute concentration
hypotonic solution: lower solute concentration

Question 11

rate and direction of ion movement through channels depends on the

Answer 11

concentration gradient and the distribution of electrical charge

Question 12

voltage-gated channels depend on what

Answer 12

the charge

Question 13

active transport

Answer 13

movement of substances across the membrane against a concentration and/or electrical gradient. energy required

Question 14

primary active transport

Answer 14

requires direct hydrolysis

Question 15

secondary active transport

Answer 15

energy comes from an ion concentration gradient that is established by primary active transport

Question 16

the sodium-potassium pump is an example of

Answer 16

primary active transport

Question 17

secondary active transport

Answer 17

aids in uptake of amino acids and sugars
involves symports (same direction) and antiports(opposite direction)

Question 18

Cell theory

Answer 18

cells are the fundamental units of life
all organisms are composed of cells
all cells come from prexsisting cells

Question 19

most cells are small. exceptions:

Answer 19

bird eggs,neurons,some algae and bacteria

Question 20

how much larger are eukaryotic cells than prokaryotic cells

Answer 20

10x

Question 21

why are cells small

Answer 21

they need a high surface area to volume ratio
volume determines the amount of chemical activity in the cell per unit time
surface area determines the amount of substances that can pass the cell boundary per unit time

Question 22

all cells are surrounded by a membrane

Answer 22

plasma membrane is made of a phospholipid bilayer

Question 23

plasma membrane functions

Answer 23

allows cells to maintain constant internal enviroment
is a selectively permeable barrier
is important to communicate and receive signals

Question 24

types of cells

Answer 24

eukaryotic and prokaryotic

Question 25

flagella in eukaryotes

Answer 25

sperm and algae

Question 26

characteristics of prokaryotic cells

Answer 26

the cytoplasm consists of the cytosol DNA is contained in nucleoid ribosomes-site of protein synthesis have a rigid cell wall outside plasma membrane bacteria have a slimy capsule of polysaccharides

Question 27

Characteristics of eukaryotic cells

Answer 27

membrane enclosed compartments calle dorganelles

Question 28

What techniques have been studied on organelles

Answer 28

microscopy and cell fractionation

Question 29

how mRNA ribosome travels in eukaryotic cells

Answer 29

cytoplasm to rer to golgi apparatus to plasma membrane then leaves the cell(exocytosis)

Question 30

how protein travels in eukaryotic cells

Answer 30

leaves mRNA then could go to organelles or the cytosol. organelles: goes to nucleus cytosol: either peroxisomes, mitochondria, or chloroplasts

Question 31

protein to the rer

Answer 31

a. signal recognition particle binds to a signal sequence in the amino-terminal end of the growing polypeptide and halts translation b. srp binds to the srp receptor on the er membrane c. the srp receptor brings the ribosme to a transmembrane channel d. the protein ends up in the lumen of the er, where it could go to another organelle or go out of the cell

Question 32

cellular respiration is

Answer 32

energy in fuel molecules is transformed into binds of energy-rich atp

Question 33

Endosymbiosis theory

Answer 33

explains how eukaryotes could evolve from prokaryotes: cells engulf other cells that became mitochondria and chloroplast

Question 34

deltaG=deltaH-TdeltaS

Answer 34

change of free energy equals change of enthalpy minus temperature times change of entropy

Question 35

negative deltaG

Answer 35

free energy is spontaneous reaction (exergonic)

Question 36

positive deltaG

Answer 36

free energy is not spontaneous (endergonic)

Question 37

exergonic reaction

Answer 37

reactants release a great amount of enrgy to the products. negative deltaG cell respiration catabolism

Question 38

endergonic reaction

Answer 38

reactants have a great amount of energy required to reach the products. positive deltaG active transport cell movement anabolism

Question 39

exergonic and endergonic reactions are

Answer 39

coupled reactions

Question 40

ATP in coupled reactions

Answer 40

ATP is often but not always involved in coupled reactions

Question 41

activation energy

Answer 41

amount of energy required to start a reaction larger the Ea the slower the reaction

Question 42

how does an enzyme accelerate the reaction

Answer 42

by reducing the Ea

Question 43

deltaG in chemical reactions

Answer 43

deltaG is the same with and without an enzyme

Question 44

uncatalyzed reaction;catalyzed reaction

Answer 44

without enzyme;with enzyme

Question 45

how do enzymes lower the energy barrier

Answer 45

by bringing the reactants togther

Question 46

catalyzed reactions reach a maximum rate faster with an enzyme or without an enzyme

Answer 46

with an enzyme

Question 47

the major metabolic pathways are

Answer 47

1. glycolysis,2.pyruvate,3.krebs cycle(cac), 4. electron transport chain

Question 48

glycolysis

Answer 48

glucose is converted to pyruvate, ATP and electron carriers

Question 49

pyruvate and krebs cycle (cac)

Answer 49

convert pyrivate into CO2,ATP and electron carriers

Question 50

electron transport chain

Answer 50

converts electron carriers and O2 into ATP and H2O

Question 51

external to mitochondrion

Answer 51

glycolysis and fermentation

Question 52

inside mitochondrion

Answer 52

inner membrane-electron transport chain matrix- citric acid cycle and pyruvate oxidation

Question 53

Glycolysis outputs

Answer 53

2 ATP and 2NADH

Question 54

inputs

Answer 54

glucose, nad+,adp+, phosphate

Question 55

outputs

Answer 55

2nadh 2atp 2 pyruvate

Question 56

pyruvate oxidation outputs

Answer 56

CO2 and nadh

Question 57

citric acid outputs

Answer 57

CO2 reduced electron carriers(nadh and fadh2) and atp

Question 58

oxidative phosphorylation

Answer 58

flow of electrons release energy energy used to pump protons concentration gradient used to make atp

Question 59

isozymes are

Answer 59

enzymes that catalyze the same reaction but have different properties such as optimal temperature