Past Papers Flashcards
Haversian canals DO NOT contain
Osteocytes processes
Which leukocyte has azurophillic granules and well developed RER and Golgi apparatus?
Monocytes
It is NOT TRUE that defensins
cooperate with myeloperoxidase in the chlorination of bacterial proteins
Which leukocyte contains three different types of cytoplasmic granules?
Neutrophils
Functions of eosinophils DO NOT include
Neutralization of mediators produced by mast cells
In the blood platelet, granulomere DOES NOT contain
Tubules storing calcium ions
Elasticity of elastic fibers results from
Expansion of the cross-links between elastin molecules
In proteoglycan aggregates, proteoglycan molecules are connected by
Glycosaminoglycans (GAGs)
It is NOT TRUE that procollagen molecules
Can aggregate with other procollagen molecules
Indicate a common feature of fibroblasts and plasma cells
Well developed RER
In the smooth muscle cell, binding of myosin to actin requires
Phosphorylation of myosin
Which cells can spontaneously (without external signal) depolarize their cell membrane?
Interstitial cells of canal
FIlaments which protect sarcomere from too excessive stretching are built of:
Desmin
In the skeletal muscle fiber, voltage-sensitive protein:
Is located in thin myofilament and pulls tropomyosin away from actin
The quadriceps muscle of 100 meter world record holder is built mostly of
White muscle fibers
In nerve cells, RER, free ribosomes and dictusomes of the Golgi apparatus are:
Poorly developed because nerve cells are not capable of proliferation and differentiation
Neurosecretory cells release peptide hormones at axon terminals. What makes it possible?
Kinesin
Suggest the correct arrangement of structures in myelinated nerve fiber (inside-out)
Axon - myelin sheath - layer of Schwann cell cytoplasm - basal lamina
Which cells have unusual apical cell membrane built of thick protein plates (plaques) interconnected by flexible areas of normal cell membrane?
Dome-shaped cells of urothelium
In stratified epithelia, dividing cells are located
In the basal layers
In the microvillus, actin filaments are connected to the cell membrane by
myosin
It is NOT TRUE that stereocilia
Contain 9 peripheral doublets and 2 central microtubules
Ciliated epithelium can transport objects along its surface because
Bending (active phase) is unidirectional but slightly delayed in successive cilia
Which transmembrane linker protein occurs in anchoring (mechanical) cell-cell and cell-ECM junctions?
Cadherins & integrins
What filaments are transmembrane linker proteins connected by?
Actin filaments
Does the basal lamina control the passage of small molecules?
No, it’s function is intense transport of molecules (ions) across the basal cell membrane. It limits the transport of big (!) molecules passing across the membrane.
Hemapoietic stem cells first differentiate into
Stem cells for lymphopoetic lineage and stem cells of other lineages
The most numerous cells present in the hematopoetic bone marrow belong to
Granulopoetic lineage
Which cell of the granulopoetic lineage is the first to contain specific granules?
Myelocyte
Nerve cells with pyriform bodies and dendritic trees immensely branched in one plane are typically observed in:
Cerebellar cortex (Purkinje cells)
In the choroid plexus, ependymal cells covering the villi are interconnected by:
Tight junctions
What is responsible for highly selective permeability of the BBB?
Endothelial cells
Integrins are NOT present in:
Intercalated disks
Name a pair of cells that have different initial origin
Osteoclasts & Osteoblasts
Continuous conduction in axon is unidirectional because:
After opening, sodium channels close and for some time are insensitive to voltage
In the myelinated nerve fiber, voltage gated sodium channels are present in
The initial segment of axon and the regions of Ranvier nodes
Do macrophages produce their own basal lamina?
No
Which band DOES NOT change during sacromere contraction?
A
Where is Alpha actinin located?
In Z-lines of sacromeres, at sites of thin myofilament interconnections in smooth muscle, at sites of thin myofilaments attachments to the cell membrane in smooth muscles
Are mast cells activated by detachment or binding of IgE from/to their receptors?
Binding
In which type of cell of CT do cells predominate over the ECS?
In adipose tissue
Type 3 collagen is predominant in:
Reticular CT
The cytoplasm of reticulocyte contains hemoglobin and
Clusters of ribosomes
What is the single lipid droplet in unilocular adipocytes surrounded by?
A network of intermediate filaments
Cancellous bone is formed by
Intramembraneous ossification
Does cancellous bone contain vascular canals or bone marrow in its trabeculae?
Bone marrow
Cancellous bone is built of
Parallel bone lamellae
Very small skeletal muscle fibers associated with numerous afferent and efferent nerve terminal are:
Intrafusal fibers and are located in muscle spindles
What is located in the meshes of 3-dimensional network formed by the contractile apparatus in the cardiac muscle cell?
Very numerous mitochondria
In the cardiac muscle, all Cardiomyocytes are interconnected by
Gap junctions
Apart from different shape, pseudounipolar neurons differ from other nerve cell types in
Pathway of impulse conduction and morphology of dendrites
What does the activity of osteoclasts’ proton pump result in?
Local demineralization of resorbed bone
What do osteoblasts do using their receptor mechanism?
Influence formation and recruitment of osteoclasts
What is the first event in endochondral ossification?
Degeneration of hyaline cartilage in the central area of the shaft
Which plasma component is produced by a cell of CT proper?
Gamma-globulins
What is mainly responsible for the resistance of hyaline cartilage to pressure?
Proteoglycan aggregates
In the elastic cartilage, elastic fibers are located:
Inside chondral territories
Haversian canals do NOT contain
Osteocytes processes
Which leukocyte contains 3 different types of cytoplasmic granules?
Neutrophils
Functions of eosinophils DO NOT include
Neutralizations of mediators produced by mast cells
In the blood platelet, granulomere DOES NOT contain
Tubules storing calcium ions
Elasticity of elastic fibers results from
Expansion of the cross-links between elastin molecules
Can procollagen molecules aggregate with other procollagen molecules?
No
Which membrane proteins transport substances by rapid cyclic changes of conformation?
Carriers and pumps
The F0 component of the mitochondrial ATP-synthase contains?
Proton transporter
The mitochondrial matrix does not contain
enzymes responsible for ATP synthase
The activity of sodium-potassium pump (NA, K-ATPase) is an example of a
Aniport
The glycocalyx is composed of
Sugar residues of membrane glycoproteins and glycolipids
The ion channels cannot be opened by
Energy from ATP
The number of ribosomes in a polyribosome depends on
Molecular weight
Which adhesion molecules bind to the extracellular substance?
Integrins
The signal sequence targeting a protein to the nucleus never occurs together with
Signal sequence for SRP
The membrane of RER is continuous with
Outer membrane of the nuclear envelope
What is transported from the nucleus to the cytoplasm through nuclear pores?
mRNA, tRNA, rRNA
The membrane of trans-face of the dictyosome is most similar to
Cell membrane
Trans Golgi network does not produce these vesicles:
Preperoxisomal
Processes occurring in the dictyosome are:
Glycosylation of proteins, phosphorylation of some sugar residues, increase in membrane thickness
In the nucleolus, granular component contains mainly
Large ribosomal subunits
The first stages of receptor-mediated endocytosis are most similar to
Pinocytosis
Which process occurs in both early and late endosomes
Separation of ligands to receptors
During formation of autolysosomes digesting of a mitochondrion the mitochondrion is first
Enclosed by ER membrane which next fuses with hydrolase vesicles
Receptors responsible for binding lysosomal enzymes in trans Golgi networks recognize
Mannose 6 phosphate residues
Products of lysosomal digestion are transported
Across the lysosomal membrane to the cytoplasm
Following ubiquination proteins are digested in
Proteasosomes
What is a common feature for phagocytosis and pinocytosis?
Membrane fusion
Aggregation of coating protein (clathrin, COP) under a membrane is necessary for
Aggregation of receptor and invagination of the membrane
What is a common function of smooth ER and peroxisomes?
Synthesis of lipids
Intermediate filament occurring in epithelial cells are built of
Cytokeratins
Plus end of microtubule undergoes frequently
Polymerization and depolymerization
The compact arrangement of nucleosides in the chromatin fiber results from aggregation of
H1 his tones
A vesicle moving towards cell nucleus is transported by
Dynein
During apoptosis mitochondria
Release cytochrome c which activates caspases
Pumps are
Transporters and enzymes
Abundant noncoding DNA sequences are present in
Constitutive heterochromatin
How many microtubules will you find in the centrosome
54
In the nucleolus pre-rRNA is
Cleaved into shorter fragments
What is the correct definition of the nuclear lamina
The inner membrane of the nuclear envelope
New peroxisomes originate from vesicles formed by
ER and their enzymes are produced on free ribosomes
Which process requires involvement of micro filaments?
Phagocytosis
The ERGIC allows
Some proteins to return to ER
Caveolae and lipid rafts are specialized areas of
Cell membrane
Which lipid present in biological membranes participates in cell signaling?
Phosphoinositiol
Coating proteins surround ALL vesicles that
Participate in vesicular transport of ligands bound to receptors
The early endosome allows recirculating of receptors to
The cell membrane
What happens to receptors for man-6-P present in hydrolase vesicles?
They recirculate to the dictyosome
Which protein is produced on RER
Histone H1
Hydrolase vesicles contain
Inactive enzymes
All mitochondrial proteins are produces
On ribosomes not attached to ER
Nucleosome is composed of
DNA and his tones
The “head” of ATP synthase complex (F1) contains
ATP synthase
Which mitochondrial membrane shows high selective permeability?
The inner one
Which function is performed by both SER and peroxisomes?
Synthesis of cholesterol
Kinesin and myosin both
Walk in the same direction
The major role in the formation of new microtubules is played by
Centrioles
After completion of the translation process on RER small ribosomal subunit
Dissociated from the large one and the large one dissociates from ER membrane
Import of protein into the target location depends on
Amino acid sequence of a small protein fragment
Which adhesion molecules bind sugar residues of adjacent cells
Selectins
In the nucleus granular component contains mainly
Large ribosomal subunits
Sorting of secretory proteins from lysosomal processes takes place in
trans-Golgi network
Transformation of chromatin from “beads on a string” into chromatin fiber is
Condensation of chromatin induced by H1 histone
Hydrolase vesicles are initially coated with
Clathrin
Autolysosomes are formed by fusion of hydrolase vesicles with
Cell constituents surrounded by ER membrane
Mitochondrial DNA encodes
Some proteins of the inner membrane
Erythrocytes and blood platelets have no nuclei, what does it result from?
The same mechanism of differentiation in the bone marrow
What cells of granulopoietic lineage are the first to occur in 3 variants (neutrophilic, eosinophilic, basophilic)?
Metamyelocytes
What cells do platelets come from?
Megakaryocytes
Which leukocyte is the most abundant in a peripheral smear of blood? (Excluding erythrocytes)
Neutrophil
Which leukocyte has a multi-blood (3-5) lobed nucleus?
Neutrophil
Approx. what percentage of the volume of blood do the formed elements compromise?
45%
Which cells are described to have a central pallor?
Erythrocytes
What is the smallest leukocyte?
Lymphocytes
What is the largest leukocyte?
Monocytes
Is it true that the bactericidal system in neutrophils is oxygen dependent and uses defensins and O2?
No
What triggers exocytosis in a mast cell?
Binding of antigen to receptor IgE complex
Antigens of ABO blood groups are…
Glycocalyx oligosaccharides of erythrocytes
How is heterochromatin distributed in a plasma cell?
There is no specific distribution
Which granules of neutrophil DO NOT participate in killing of bacteria?
All granule types contain components of the bacteria-killing system
Hyalomere of the blood platelet DOES NOT contain granules with
clotting factors
Which leukocyte has azurophilic granules and well developed RER and Golgi apparatus
Monocytes
In the blood platelet, the Hyalomere does not contain which organelle?
Mitochondria
Leukocyte granules which stain with eosin contain
Major basic protein
Which blood cells have a common CFU progenitor cell in bone marrow?
Neutrophils and monocytes
How do mature blood cells enter the blood coagulation in the bone marrow?
Through transient, large pores in the endothelial cells of blood vessels
Azurophilic granules in leukocytes are a special kind of
Hydrolyse vesicles
Blood platelets aggregate at a site where:
Collagen of the vascular wall is exposed to the bloodstream
What is common for fibroblasts and plasma cells
Characteristic pattern of heterochromatin in the cell nucleus
Which sarcomata protein DOES NOT occur in I band?
Myosin
Which band DOES NOT change during sarcomata contraction?
A
What is located in the meshes of 3-dimensional network formed by the contractile apparatus in the cardiac muscle cell?
Very numerous mitochondria
After binding Ca ions, troponin…
Pulls tropomyosin away from actin
Which fiber is made up of fast-twitch muscle?
White fibers
What is myosin
Muscle fibers
Which type of tissue is a tendon composed of?
Dense regular CT
Smooth muscle cells DO NOT contain
Miofibrils
T tubules in the skeletal muscle fiber contain…
Membrane receptors for acetylcholine
During contraction of the skeletal muscle which element does not undergo shortening?
Miofilaments
In the sacromere, M line is formed by…
Transversian protein bridges between thick myofilaments
What cells are capable of spontaneous depolarization of cell membrane?
Interstitial cells of Cajal
Filaments which protect sarcomere from too excessive stretching are built of…
Titian
What is common for skeletal and cardiac muscle?
Structure of the contractile apparatus
Smooth muscle cells are not striated because…
The contractile apparatus has no sarcomeres
