MCQ 1 Flashcards
In which of the following processes are the chaperons
involved?
Protein folding
Characteristic reaction to the medial Golgi
Removal of some non-phosphorylated mannose residues.
These processes all occur in mitochondria, except: A) Citric acid cycle B) Translation C) Beta oxidation D) Transcription E) Glycolysis
Glycolysis
True for mitochondria
A) A 20-80 amino acid signal peptide is located on the N-terminal of the proteins to be imported into
mitochondrium
B) Import of proteins does not require chaperones
C) Protein synthesis of mitochondrium – similarly to
the cytoplasm – requires 64 types of tRNAs
D) Passing through the outer membrane of
mitochondrium by proteins is highly dependent
on the potential gradient measured
E) Cardiolipin content of the eukaryotic plasma
membrane is synthesized also in mitochondria
A) A 20-80 amino acid signal peptide is located on the N-terminal of the proteins to be imported into
mitochondrium
What are the major characteristics of the facilitated
diffusion?
A) This process provides a facilitated transport of
molecules without energy and transmembrane
proteins
B) This is an active transport that facilitates the
transport of glucose across the plasma membrane
C) It is the process of passive transport via transport
protein
D) It is mediated only by ion channels
E) Molecules and ions move against their
concentration gradient
C) It is the process of passive transport via transport
protein
- In general, it requires active membrane transport:
A) Uptake of LDL particle
B) Glucose uptake by facilitated diffusion
C) Ca2+ transport via ion channels
D) Transport of nucleotides
E) Engulfing of microorganisms
D) Transport of nucleotides
The constitutive heterochromatin:
A) Makes up the nucloskeleton (NO)
B) Carries out transcription, consequently it is
electron dense NO
C) Can be anchored to the nuclear lamina (YES)
D) Contains genes which are required for the
fundamental cell physiological functions (NO, has very few genes)
E) Provides genetic information for the synthesis of
ribosomes
C) Can be anchored to the nuclear lamina
Which highly condensed subcompartments of nucleolus is
formed by the nucleolar organizer region (NOR) of the
chromosomes?
A) Fibrillar center (FC)
B) Granular component (GC)
C) Dense fibrillar component (DFC)
D) GC + DFC
E) None of the above answers are correct
A) Fibrillar center (FC)
Protein(s) synthesized on polyribosomes: A) Acetylcholine-receptor B) Histones C) Acid hydrolases D) Glycosyl transferase E) Insulin
B) Histones
Which of the following processes occurs in the lumen of
rER?
A) Key steps of phospholipid biosynthesis
B) Loading of amino acid onto the tRNA
C) Co-translation membrane transport
D) Formation of disulphide bonds X
D) Formation of disulphide bonds
In which group do the terms belong together?
A) Basophilia, rER, hematoxylin
B) Basophilia, sER, hematoxylin
C) Acidophilia, nucleus, hematoxylin
D) Acidophilia, nucleus, eosin
E) Eosinophilia, acidophilia, rER
A) Basophilia, rER, hematoxylin
How do the resolving powers of the light microscope and
the transmission electron microscope relate to each other?
A) They are about the same
B) The resolving power is 1000x higher in the case
of the TEM
C) It is depending on the magnification
D) The resolving power is 100x higher in the case of
the TEM
E) None of the above answers is correct
B) The resolving power is 1000x higher in the case
of the TEM
The correct sequence of the chemicals used during the
embedding for TEM:
A) Propylene oxide, ethanol, plastic resin
B) Ethanol, xylene, paraffin
C) Ethanol, propylene oxide, epoxy resin
D) Epoxy resin, propylene oxide, ethanol
E) Ethanol, xylene, epoxy resin
A)
What is a criteria of terrestian life?
A) Motility
B) Stable internal environment
C) Energy production
D) Responsiveness to visual signals
E) Ability to do detoxification
B) Stable internal environment
Which statement is true?
A) According panspermy theory, meteorite may
carry organic compound
B) In Oparin`s coacervate composed by gelatin and
oil, organic molecules appear after one week
incubation
C) The positively charged clay or pyrite as an
absorptive catalyzer surfaces (prebiotic pizza)
provided an optimal surface for cell adhesion
D) According prebiotic pancake theory, the building
blocks were formed in the primordial soup, but
polymerization took place in air
E) Enzymatic activity for some RNA (e.g.
ribozyme), contradict to the RNA word theory
A) According panspermy theory, meteorite may
carry organic compound
An anticodon is found in:
A) mRNA
B) rRNA
C) tRNA
D) the newly synthesized protein
E) DNA
C) tRNA
We do not use it as a chemical fixative:
A) Ethylalcohol
B) paraformaldehyde
C) Methylalcohol
D) Heavy metal salts
E) Xylene
E) Xylene
According to the central dogma:
A) The sequence of nucleotides in DNA determines
the primary structure of a protein
B) The sequence of amino acids in a polypeptide is
determined by the ribosome
C) Each codon in mRNA encodes more than one amino acid
D) Ribosomes are the sites of transcription in the
cell
E) Each amino acid can bind to one tRNA
A) The sequence of nucleotides in DNA determines
the primary structure of a protein
What can be calculated by the Abbe`s equation?
A) The minimal distance on the microscopic image
B) Magnification of objective lens
C) Semiangle of the objective lens
D) Total magnification of LM
E) Magnification of eyepiece lenses
A) The minimal distance on the microscopic image
The aim of the ……….. is to give a mechanical support to the specimen
A) Sectioning finn på huskeregel
B) Embedding
C) Fixation
D) Covering
E) Staining
B) Embedding
The acidophilic compounds are:
A) Anionic
B) Acidic
C) Cationic
D) Hydrophobe
E) None of them
A) Anionic
Where can an SRP-R (signal recognition particle receptor) be found? A) In nuclear pore complex B) In nucleolus C) In the inner nuclear membrane D) In the membrane of ER E) In the lumen of ER
D) In the membrane of ER
The cell membrane is composed of:
A) Phospholipids and cholesterol
B) Proteins, phospholipids and cholesterol
C) Cholesterol, phospholipids, proteins and
carbohydrates
D) Nucleic acids, phospholipids and carbohydrates
E) Proteins and carbohydrates
C) Cholesterol, phospholipids, proteins and
carbohydrates
What electrons are the most important in the image
formation of SEM?
A) Secondary ones
B) Adsorbed ones
C) Resorbed ones
D) Scattered ones
E) Absorbed ones
A) Secondary ones
What is the name of “n sina” in the Abbe`s equation?
A) Semi aperture of the objective
B) Numerical aperture
C) Semi angle of the aperture
D) Minimal distance
E) Refractive index
C) Semi-angle on aperture
The aim of the ……. Is to preserve the structure
characteristic to living organism
A) Sectioning
B) Embedding
C) Fixation
D) Casting
E) Infiltration
C) Fixation
What substance may be used for embedding during TEM
microtechnics?
A) Canada balm
B) Paraffin
C) O2O4
D) Plastic resin
E) Glutaraldehyde
D) Plastic resin
What is a role of SRP (signal recognition particle)?
A) Nucleo-cytoplasmic transport
B) Recognition of NLS
C) Recognition NES
D) Recognition of ER signal sequence
E) Proteolysis of ER signal sequence
D) Recognition of ER signal sequence
Phospholipid molecules have ………. head groups and
……….. Tail groups
A) Hydrophilic; hydrophilic
B) Hydrophobic; positively charged
C) Hydrophilic; hydrophobic
D) Hydrophobic; hydrophilic
E) Negatively charged; hydrophobic
D) Hydrophilic; hydrophobic
Where can a TATA box be found?
A) In prokaryotic promoter
B) In prokaryotic mRNA
C) In eukaryotic primary transcript
D) In eukaryotic promoter
E) In none of them
D) In eukaryotic promoter
What is in the dense fibrillary compartment (pars fibrosa)?
A) rDNA
B) pre-rRNA
C) pre-ribosomes
D) ribosomes
E) none of them
C) Pre-ribosomes
Active transport is different from simple diffusion and
passive transport in that it:
A) Need carrier protein
B) Does not require an input of energy
C) Involves the expenditure of energy
D) Can be used to transport molecules across the
cell membrane
E) Cannot be used to transport molecules across the
cell membrane
C) Involves the expenditure of energy
The contrast of electron microscopic image is enhanced by
the following:
A) U, Pb and O2
B) Pb, P and O2
C) U, NA and Ca
D) U, P and O2
E) U, Pb and K
A) U, Pb and O2
Which of the following does Not have a membrane?
A) Peroxisome
B) Nucleus
C) Nucleolus
D) Ribosome
E) Both C and D
E) Both C and D
- A certain protein is 60 amino acids long. How many
nucleotides are required in DNA to code for this protein?
A) 20
B) 30
C) 60
D) 120
E) 180
E) 180
What electrons are the most important in the image
formation of TEM?
A) Secondary ones
B) Adsorbed ones
C) Resorbed ones
D) Scattered ones
E) Absorbed ones
D) Scattered ones
Which is a very frequent sequence motive of eukaryotic
gene promotor?
A) AUG
B) TAC
C) TATA
D) TAGA
C) TATA
What is in the fibrillar center (pars amorpha)?
A) rDNA
B) pre-rRNA
C) pre-ribosomes
D) ribosomes
E) none of them
B) Pre-rRNA
The movement of molecules from a region of high
concentration to lower concentration is:
A) Simple diffusion
B) Passive transport
C) Active transport
D) Uniport transport
E) Both A and B
E) Both A and B
Water molecules may cross the membrane by
A) Cotransport
B) Active transport
C) Passive transport (facilitated
transport)
D) Uniport transport
E) Symport transport
C) Passive transport (facilitated transport)
Which of the following structures is present in ALL
eukaryotic and prokaryotic cells?
A) Mitochondrium
B) Nucleus
C) Ribosome
D) RER
E) SER
C) Ribosome
The ubiquitin
A) Is an important signal that directs proteins to the
nucleus
B) Is a signal sequence present at the N-terminal of
proteins which are synthesized on ribosomes
attached to the endoplasmic reticulum
C) Is a second messenger
D) Is a signal for protein degradation via the
proteasome
E) Can be found in the proteins targeted to the
peroxisomes
D) Is a signal for protein degradation via the
proteasome
Which of these statements is false for trygocytosis?
A) It involves transfer of mitochondria from one cell
to the other
B) It represents transfer of membrane patches from
one cell to the other
C) The consequence of trogocytosis is the transfer of
cell surface receptors
D) Trogocytosis represents transfer of membrane
phospholipids as well
E) Trogocytosis results in the cell surface
appearance of molecules not synthesized within
the cell
A) It involves transfer of mitochondria from one cell
to the other
Energy is required for the following processes, except:
A) For the assembly of clathrin coat
B) For moving of ribosomes to the next mRNA
codon
C) For the polymerization of the microtubules
D) For the Na+/K+ pump
E) For the gated transport
E) For the gated transport
Characteristic to chemokinesis
A) Migration of cells is elicited by the mechanical
stimuli of the environment
B) It is elicited by substances released from dead
cells
C) Human cells express never show type of
migration
D) It is elicited by chemicals and the direction of
movement has a random character
E) Vectorial movemen
D) it is elicited by chemicals and the direction of movement has a random character.
Which of the following statements is false for the nuclear
lamina?
A) It is a protein network underneath the inner
nuclear membrane
B) One of its functions is the anchoring of
peripheral heterochromatin
C) The meshwork like structure is connected to the
nucleoskeleton
D) It is made of lamins
E) It makes connection to the inner nuclear
membrane and chromatin, as well
E) It makes connection to the inner nuclear
membrane and chromatin, as well
The NOR
A) Is a special region in all chromosomes
B) Participates in organizing the nucleoskeleton
C) Contain genes for all tRNA molecules
D) Is chromosomal region where the nucleolus is
formed around
E) None of the above answers is correct
E) None of the above answers are correct
Protein(s) synthesized on ribosomes of rER:
A) LDL receptor
B) Mitochondrial ATP-ase
C) Monomeric G-proteins
D) Actin
E) Histones
C) Monomeric G-proteins
Which of the following statements is true?
A) The mannose-6-phosphate signal can be found in
the secretory proteins
B) The sorting signal is added to the lysosomal
proteins in the trans-Golgi network
C) The ER- and Golgi resident proteins contain
retention signals
D) The targeting signal of cytosolic proteins is present at the C-terminal end
E) All of the above answers are correct
B) The sorting signal is added to the lysosomal
proteins in the trans-Golgi network
Phospholipase C activation leads to:
A) Decreased PIP2 and DAG level
B) Increased IP3 and decreased DAG level
C) Decreased IP3 and increased Ca2+ concentration
D) Increased PIP2 and increased Ca2+
concentration
E) Increased IP3 and increased Ca2+ concentration
E) Increased IP3 and increased Ca2+ concentration
What is the most determining factor of the resolving
power in light microscopy?
A) The wavelength of the illuminating light and the
lens opening semi-angle
B) The wavelength of the illuminating light and the
objective opening semi-angle and refractive index
of the material between objective and the sample
C) The wavelength of the illuminating light and the
ocular opening semi-angle and refractive index of
the material between ocular and the sample
D) The wavelength of the illuminating light and the
objective opening semi-angle and refractive index
of the material between ocular and the sample
E) The intensity of the illuminating light and the
objective opening semi-angle and refractive index
of the material between objective and the sample
B) The wavelength of the illuminating light and the
objective opening semi-angle and refractive index
of the material between objective and the sample
Cytoplasmic basophilia is resulted by:
A) Granules of motorneurones stained
ortochemically by cresyl violet
B) Glycogen granules of liver cells
C) Zymogenic granules of apical parts of pancreas
acini
D) Large membrane system of rER in cells of
ganglion spinale
D) Large membrane system of rER in cells of
ganglion spinale
The correct sequence of the used chemicals during the
embedding for LM:
A) Paraffin, ethanol, xylene
B) Ethanol, paraffin, xylene
C) Xylene, ethanol, paraffin
D) Ethanol, xylene, epoxy resin
E) Ethanol, xylene, paraffin
E) Ethanol, xylene, paraffin
What is the solenoid or chromatin fiber?
A) It consists of RNA wound in histone protein core
B) It is a 30 nm fiber consisting of packed
nucleosomes
C) It is the beads-on-a-string form of chromatin
D) It is heterochromatin wrapped around H1 histone
E) It is a ribonucleoprotein particle
B) It is a 30 nm fiber consisting of packed
nucleosomes
Various functions of the nuclear lamina are except:
A) Maintenance of nuclear envelope and nuclear shape
B) Spatial organization of nuclear pores within the nuclear membrane
C) Regulation of translation
D) Anchoring of interphase heterochromatin
E) Role in DNA replication, lamins are found within the nucleoplasm (internuclear filaments) and these lamin foci are often associated with sites of DNA replication
C) Regulation of translation
Motorprotein interacting with actin microfilaments:
A) Myosin
B) Dynein
C) Keratin
D) Kinesin
E) Collagen
A) Myosin
The disadvantage of using frozen sections is:
A) It causes irreversible structural changes in the specimen
B) It cannot be used fro demonstration of lipids
C) It has a limite use because of being time consuming
D) It cannot be used prior to enzyme histochemical reactions
E) It requires a special microtome to prepare the sections with
E) It requires a special microtome to prepare the sections with (?)
Characteristic to an acidic dye:
A) Stains the acidic components of the cell
B) Stains metachromatically e.g. heparin
C) Cresyl-violet is an acidic dye
D) It detects several cytoplasmic proteins as well as histones
E) In some cases we can use these dyes as a fixative (e.g. OsO4)
D) It detects several cytoplasmic proteins as well as histones
We do not use it as a chemical fixative:
A) Ethylalcohol
B) Formaldehyde
C) Epoxy resin
D) Heavy metal salts
E) Methylalcohol
C) Epoxy resin
Becuase steroids generally act by ____, their effects are typically ____ than the effects of peptide hormones
A) Regulating transcription; slower
B) Activating second messengers; slower
C) Opening ion channels; Faster
D) Regulating transcription; faster
E) Activating G proteins; slower
A) Regulating transcription; slower
The main types of extracellular vesicle, except:
A) Exosome
B) Apoptotic bodies
C) Large oncosome
D) Transport vesicle
E) Microvesicle
B) Apoptotic bodies
What is the nucleosome?
A) It is the structural unit of chromatin
B) It is a pre-ribosomal unit in the nucleolus
C) It is composed of pre-mRNA and histone proteins
D) It is composed of rDNA and non-histone proteins
E) It is nuclear unit of inactive transcription factors
A) It is the structural unit of chromatin
What is the function of nucleolus?
A) Coding of ribosomal proteins
B) mRNA synthesis
C) Assembly of ribosomal subunits
D) Ribosomal protein synthesis
E) rDNA synthesis
D) Ribosomal protein synthesis
The SRP
A) Recognises all the signals found at the N terminus of proteins
B) Is involved in sorting of all proteins
C) Is a chaperon
D) Targets free ribosomes to rER membrane by recognizing an amino acid sequence at the N terminus of synthesized protein
E) Targets ribosomal subunits from the nucleolus to the cytosol by recognizing….
D) Targets free ribosomes to rER membrane by recognizing an amino acid sequence at the N terminus of synthesized protein
When a chemical messenger (or ligand) reaches a target cell, it binds to a receptor. A hydrophobic ligand binds to a(n) _____, whereas a hydrophilic ligand binds to a(n)____:
A) Intracellular receptor; transmembrane receptor
B) Transmembrane receptor; intracellular receptor
C) Autocrine receptor; paracrine receptor
D) Transmembrane receptor; nuclear receptor
E) Both first to transmembrane receptor then to a nuclear receptor
A) Intracellular receptor; transmembrane receptor
What is not true for Golgi?
A) It can be detected in TEM preparation by Ag impregnation
B) The oligosaccharide chains of proteins are modified in the Golgi
C) All the proteins become O-glycosylated in the Golgi
D) Some proteins are phosphorylated in cis-Golgi
E) The protein sorting takes place through the whole Golgi
C) All the proteins become O-glycosylated in the Golgi
How do vesicles travel down the axon of a nerve cell?
A) They are carried by dynein motors down flagella
B) They are carried by kinesin motors down microtubules
C) They diffuse down their concentration gradients
D) They are carried by myosin down actin microfilaments
E) They are carried by kinesin motors down microfilaments
B) They are carried by kinesin motors down microtubules
Which of the following is a function of the Golgi complex?
A) Protein synthesis
B) Modifying and packaging of lipids and proteins into vesicles
C) Lipid synthesis
D) Ca2+ storage in muscle cells
E) Ribosome synthesis
B) Modifying and packaging of lipids and proteins into vesicles
Which statement is true for Urey-Miller experiment:
A) The primitive atmosphere was mimicked by mixture of methane, water, hydrogen, oxygen
B) Lightning was stimulated by lamp
C) After one day Miller identified lipids and saccharides
D) At the end of one week experiment Miller identified five amino acids
E) The experiment was repeated by Aleksandr Ivanovich Oparin
D) At the end of one week experiment Miller identified five amino acids
What is true for glycocalyx:
A) Proteoglycans absorbed to it are oligosaccharides composed by maximum 15 hexoses
B) It protects the cells against bacteria
C) The glycocalyx is rich in positively charged chemical groups and therefore can be visualized by applying negatively charged colloidal stains
D) Glycocalyx is hydrophobic
E) Glycocalyx does not participate in receptor mediated processes
B) It protects the cells against bacteria
Which of these is NOT part of vesicular transport of the cell?
A) Late endosome
B) Endoplasmic reticulum
C) Lysosomes
D) Golgi complex
E) Peroxisomes
E) Peroxisomes
Histone proteins
A) Core region of nucleosomes formed by trimerization
B) The distance between these proteins is about 60 bp
C) they have a role also in regulation of translation
D) They are organized around the constitutive heterochromatin
E) Majority of these proteins is phylogenetically well conserved
E) Majority of these proteins is phylogenetically well conserved
True for the nucleus
A) Heterochromatin is associated always to its pores
B) It has an internal skeleton
C) Its chromatin is composed mostly by DNA and lower part proteins and nucleolipids
D) Its location is close to the basal part of the cell
E) Contains bare DNA in prokaryotes
B) It has an internal skeleton
Which cellular activity is NOT characteristic to rER?
A) Synthesis of secretory proteins
B) Glycosylation of proteins entering rER
C) Synthesis of histones
D) Oligosaccharide-transferase activity
E) Its membrane contains dolichol
C) Synthesis of histones (?)
They are second messengers:
1) Ca2+
2) SRP
3) IP3
4) ATP
A) 1,2,3
B) 1,3
C) 2,4
D) 4
E) 1,2,3,4
B) 1,3
What is autophagy?
A) During this process the enzymes released from the lysosomes digest self composing elements of the cell
B) This process is started by formation of isolating membrane
C) Belongs to the receptor mediated endocytosis
D) It is observed only in dying cells
E) It is essentially the same as apoptosis
? E) It is essentially the same as apoptosis
Characteristic to caveolas
A) They are covered by clathrin layer
B) They possess coatomer-coverage
C) COP proteins are their building elements
D) They participate in micropinocytosis
E) They participate in potocytosis
E) They participate in potocytosis
Essential factors that determine chemotactic ability of eukaryotic cells
A) Concentration gradient of chemicals which are detectable even in relation of the cell size of the migrating cell
B) Temperature of substances inducing cell migration
C) Magnetic field
D) Number of migrating cells
E) The detectable concentration gradient by swimming of eukaryotic cell
A) Concentration gradient of chemicals which are detectable even in relation of the cell size of the migrating cell
