Cytology Flashcards
Eukaryotic cell differs from the prokaryotic cell by the:
a) presence of histones in the cell nucleus
b) different shape of endoplasmic reticulum
c) absence of the cell wall in the all types of eukaryotic cells
d) presence of the nuclear envelope
a, d
The plasma membrane can by characterised as a:
a) rigid envelope of the cell
b) three-layer structure composed of two hydrophilic and one hydrophobic layer
c) phospholipid bi-layer
d) barrier freely permeable for polar substances (ions etc.)
b,c
The plasma membrane:
a) is composed only of membrane phospholipids
b) contains phospholipids and proteins
c) do not contain cholesterol
d) can be described as a fluid mosaic
b,d
Endocytosis:
a) is passive transfer of substances across the plasma membrane
b) is the mechanism of material transfer inside the cell
c) can be mediated by specific receptors
d) is the opposite to pinocytosis (transport of material outside of the cell)
b,c
Mitochondria:
a) are sometimes called the ”cell power plant”
b) contain their own DNA
c) are probably descendants of symbiotic bacteria
d) are present only in the animal cells, plant cells have chloroplasts instead of them
A,b,c
Mitochondria:
a) produce energy through the conversion of ADP to ATP
b) contain enzymes of the Krebs cycle
c) are inherited from father´s side (localised at the basis of sperm flagellum)
d) are two-membrane organelles
a,b,d
Ribosomes are:
a) enveloped by a single membrane
b) composed of RNA and proteins
c) necessary for the DNA transcription into RNA
d) polyanionic structures and are therefore stained with basic dyes
B,d
Ribosomes:
a) are composed of two subunits
b) can bind mRNA in greater numbers and form polysomes
c) play important role in proteosynthesis
d) in the cell nucleus translate mRNA into proteins
A,b,c
Endoplasmic reticulum:
a) is a place of tRNA synthesis
b) can be in some cells divided into granular and agranular endoplasmic reticulum
c) is necessary for the maturation of majority of secreted proteins
d) is formed by the rigid net of cytoskeletal proteins
B,c
Granular endoplasmic reticulum:
a) is associated with ribosomes
b) contains enzymes for the protein glycosylation
c) produce energy for the cell movement
d) is continuous with smooth endoplasmic reticulum
A,b,d
Golgi apparatus:
a) is functionally and structurally connected to endoplasmic reticulum
b) is a cell ”digestive system”
c) contains enzymes modifying proteins by sulfatation and glycosylation
d) communicates with endoplasmic reticulum by transport vesicles
A,c,d
Lysosomes:
a) are sites of intracellular digestion
b) have highly basic lumen (pH 10 or more)
c) are multiplied in phagocyting cells
d) are enveloped by single membrane
A,c,d
Microtubules are:
a) heterodimers composed of α and β tubulin
b) one of the cytoskeletal fibres
c) forming centrioles
d) main cytoskeletal fibers in flagella and cilia
A,b,c,d
Actin filaments:
a) are rigid fibers forming the shape of the cell
b) are associated with myosines
c) play an important role in the cell movement
d) enable contraction of muscle cells
B,c,d
Intermediate filaments:
a) are rigid fibers forming the shape of the cell
b) in epithelial cells consist of keratins
c) are formed from different proteins in different cell types
d) can associate with myosins and play role in vesicle transport inside the cell
A,b,c
