exam 4 quiz Flashcards
Which of the following statements about proteoglycans is true?
Question 1 options:
a) They consist of chains of repeating disaccharide units connected to a protein core.
b) They are found in very low amounts in the basement membranes.
c) They are extremely fragile and are restricted to selected tissues.
d) Both (b) and (c) are correct.
a. They consist of chains of repeating disaccharide units connected to a protein core.
Which one of the following is not found in the extracellular matrix?
Question 2 options:
Collagen
Laminin
Fibronectin
Actin
actin
Desmosomes are ________.
Question 3 options:
disk-shaped adhesive junctions
restricted to cardiac muscle tissue
devoid of cadherins, but rich in intermediate filaments.
All of these are correct answers
disk-shaped adhesive junctions
In the early embryo, cells detach from an epithelium and transform into individual, migrating cells. This is thought to be due to _________________.
Question 4 options:
the cytoplasm taking on an anti-adhesive character
a loss of expression of E-cadherin genes
autophagy of the nucleus
an increase in the expression of E-cadherin genes
a loss of expression of E-cadherin genes
Gap junctions are composed entirely of membrane protein subunits called __________.
Question 5 options:
Occludins
Claudins
Connexins
Connexons
Connexins
Which of the following would cells interact with for the proper formation of a branching organ such as the salivary gland?
Question 6 options:
Collagen
Proteoglycans
Actin
Fibronectin
Laminin
Fibronectin
What is the most plentiful protein in the human body?
Question 7 options:
ATP synthase
actin
myosin
collagen
collargen
collagen
Which cell adhesion molecule below binds to a short sequence of carbohydrates on the cell surface?
Question 8 options:
adherins
cadherins
selectins
calmodulins
calpains
selectins
Adherens junctions hold cells together using ____________ attached to ______________.
Question 9 options:
integrins; microfilaments
cadherins; microfilaments
cadherins; intermediate filaments
integrins; intermediate filaments
adherins; microfilaments
cadherins; microfilaments
You inject a fluorescent dye into a single cell on the surface epithelium of a microscopic animal. After a brief period of time, the dye spreads to cells neighboring the injected cell. What does this suggest?
Question 10 options:
The cells are connected by gap junctions
The cells are connected by tight junctions
The cells are connected by plasmodesmata
The cells are connected by adherens junctions
The cells are connected by gap junctions
Epithelial tissues _________.
Question 11 options:
consist of extracellular materials, including a variety of distinct fibers.
often contain cells scattered throughout the tissue
contain tightly packed cells and line spaces within the body.
All of these are correct
contain tightly packed cells and line spaces within the body.
The degradation of extracellular materials is accomplished largely by_____________.
Question 12 options:
matrix metalloproteinases
ubiquitins
protein kinases
fibronectin
matrix metalloproteinases
Which of the following statements about integrins is true?
Question 13 options:
They anchor cells to the substrate
All of these statements are true.
Different cell types are restricted to just one type of integrin
They are found in both animal and plant cells
They anchor cells to the substrate
Why do cells flatten out as they make contact with a surface?
Question 14 options:
They lose water
They send out projections that make increasingly stable attachments.
They extrude cytoplasm
Their membranes stiffen
They send out projections that make increasingly stable attachments.
Which of these cells would you expect to have very little or no integrin protein on the surface?
Question 15 options:
Red blood cells
Epidermal cells
Intestinal epithelial cells
Fibroblasts
Red blood cells
A mutation in an integrin protein results in the deletion of the cytoplasmic domain. How will this affect the ability of a fibroblast to crawl?
Question 16 options:
There will be no effect
Its ability to attach and crawl will be greatly reduced because it will not be able to form focal adhesions
It will crawl faster because the integrins will be free to float in the membrane
Its ability to attach and crawl will be greatly reduced because it will not be able to form focal adhesions
A mutation in the cytoplasmic domain of an integrin protein prevents it from binding to intermediate filaments. Which of these is a likely symptom?
Question 17 options:
a) There will be no effect
b) The epithelial layers of the skin will peel away and blister
c) The ability of neural crest cells to crawl will be reduced
Both b) and c)
b) The epithelial layers of the skin will peel away and blister
The tightest attachment between a cell and its extracellular matrix is seen at the site where an epithelial cell is attached to the underlying basement membrane. The specialized adhesive structure found at such a site is called a(n) ________.
Question 18 options:
hemidesmosome
tight junction
plasmodesma
spot desmosome
hemidesmosome
What kind of cell adhesion molecule on vessel walls mediates transient interactions to trap circulating white blood cells at sites of inflammation?
Question 19 options:
cadherins
selectins
IgSFs
integrins
selectins
Metastatic cells are distinguished by the fact that they ______.
Question 20 options:
are unable to invade other tissues, while normal cells can
are less adhesive than other cells.
are less adhesive than other cells and they are able to penetrate the basement membranes lining blood vessels.
are able to penetrate the basement membranes lining blood vessels
are less adhesive than other cells and they are able to penetrate the basement membranes lining blood vessels.
An enzyme that removes hydrogen ions from its substrate is a ________.
Question 1 options:
dehydrogenase
kinase
transferase
hydrolase
isomerase
dehydrogenase
H+ ions are able to enter the a subunit and bind to _____________, which then forms _____________ and causes the c subunit to rotate.
Question 2 options:
aspartate; aspartic acid
aspartame; aspartic acid
aspartic acid; aspartate
aspartame; aspartate
aspartate; aspartic acid
Which components of ATP synthase move/rotate?
Question 3 options:
c ring and alpha/beta hexamer ring
c ring, central stalk, alpha/beta hexamer ring
c ring, a subunit, and central stalk
c ring and central stalk
c ring and central stalk
As the electrons are transferred from Cytochrome Oxidase (ETC complex IV) to an acceptor, the energy released is used to _____________.
Question 4 options:
transport protons against their concentration gradient to the intermembrane space
transport protons down their concentration gradient to the intermembrane space
synthesize ATP
recycle Cytochrome C
form the bonds in H2O
transport protons against their concentration gradient to the intermembrane space
An uncoupling protein often works by __________ the permeability of the ______________ membrane.
Question 5 options:
decreasing; inner mitochondrial
decreasing; outer mitochondrial
increasing; inner mitochondrial
increasing; inner mitochondrial
increasing; inner mitochondrial
What is the purpose of uncoupling proteins in mammalian brown adipose tissue?
Question 6 options:
They help the tissue expand and contract when needed
They allow muscles to contract more efficiently
They function as a source of heat production during exposure to cold temperatures
They give the tissue its color
They allow the production of a larger number of ATPs per glucose
They function as a source of heat production during exposure to cold temperatures
What advantage do you think the cristae confer on the mitochondria?
Question 7 options:
They greatly increase the surface area for aerobic respiration machinery
They allow swelling of mitochondria
They activate the matrix
They allow the mitochondria to shrink.
They greatly increase the surface area for aerobic respiration machinery
The inner mitochondrial membrane has characteristics in common with _________
Question 8 options:
Bacterial cell membrane
Cardiac muscle cell membrane
Bacterial cell membrane
What is the role of O2 in the electron transport chain?
Question 9 options:
Electron acceptor
Binds to proteins
Electron donor
Fuel for heat
Electron acceptor
This graph illustrates the free energy relative to oxygen of the electron transport chain. The solid blue circles are electron carrier molecules, and the light blue ovals represent protein complexes.
graph line goes down and it is talking about free energy vs direction of electron flow
From an energy standpoint, are these reactions endergonic or exergonic?
Endergonic
Some are exergonic and others are endergonic
There is not enough information
Exergonic
exergonic
Where is ATP synthase located in eukaryotic cells?
Question 11 options:
Cytoplasm
Inner mitochondrial membrane
Outer mitochondrial membrane
Matrix of mitochondria
Inner mitochondrial membrane
Where do the H+ ions accumulate as a result of the ETC?
Question 12 options:
Matrix
Extracellular matrix
Cytosol
Intermembrane space
Intermembrane space
Which direction is the ATP synthase pointing?
*pic of atp synthase mushroom thing
Question 13 options:
F0 base opens to Intermembrane space
F0 base opens to Matrix
F0 base opens to Intermembrane space
Where does the ATP end up?
*pic of atp synthase mushroom thing
Question 14 options:
Intermembrane space
Extracellular space
Matrix
Matrix
Which of the following describes what is happening when the beta subunit of the F1 region is in the loose conformation?
Question 15 options:
ADP and Pi are able to enter
ADP and Pi are trapped
ADP and Pi are released
ADP and Pi combine to form ATP
ADP and Pi are trapped
What molecule accepts the electrons that drop off of the end of the mitochondrial electron transport chain?
Question 16 options:
NADPre
H2O
O2
NADre
CO2
O2
Which of the following complexes in the ETC pump H+ ions into the intermembrane space?
Question 17 options:
I, III, IV
I, II, IV
I, II, III, IV
I and III
I, III, IV
What molecule is produced when electrons drop off of the end of the mitochondrial electron transport chain and attach to another molecule?
Question 18 options:
H2O
CO2
NADre
O2
NADPre
H2O
The TCA (Krebs) Cycle __________.
Question 19 options:
produces NAD
makes biochemicals used to make glycogen
makes biochemicals used to make triglycerides
produces ATP and NADH
produces NADP
produces ATP and NADH
What drives the rotation of the F1 head of ATP synthase?
Question 20 options:
proton movement from the cytoplasm to the intermembrane space
ATP hydrolysis
proton movement from intermembrane space to the matrix
ATP condensation
proton movement from the matrix to the intermembrane space
proton movement from intermembrane space to the matrix
