1.CYTOLOGY
Directions
: each of the following statements contains five suggested completions.
Choose the one that is best in each case.
1. Each of the following statements concerning the plasmalemma is true, EXCEPT:
A
– includes elementary cell membrane; B – its supermembranous layer consists of
glycolipids and glycoproteins; C
– its submembranous layer contains filaments and
microtubules; D
– is a semi-permeable cell boundary; E – is not an obligatory cell
component.
2. The plasma membrane functions are as follows, EXCEPT:
A
– is a selectively permeable barrier; B – is the site for hormone receptors; C – provides
cell-to-cell interaction; D
– is the primary protein synthesis site; E – takes part in the active
and passive transport.
3. Each of the following statements concerning the microvilli is true, EXCEPT:
A
– are plasmalemma projections; B – contain microtubules; C – amplify cell surface area;
D
– form the brush border of intestinal epithelium; E – contain microfilaments.
4. Each of the following statements concerning the cilia is true, EXCEPT:
A
– are plasmalemma projections; B – contain nine peripheral doublets and the central
pair of microtubules; C
– are not visible in light microscope; D – their basal bodies are
similar to centrioles; E
– are movable organelles.
5. The intercellular junction where ionic channels pierce the adjacent membranes is
called:
A
– desmosome; B – nexus; C – tight junction; D – synapse; E – lateral interdigitations.
6. The disk-shaped intercellular junction where a dense plaque with filaments is
present on the cytoplasmic surface of each opposing plasma membrane is called:
A
– desmosome; B – nexus; C – tight junction; D – synapse; E – lateral interdigitations.
7. The intercellular junction that blocks the substance access to the intercellular
space is called:
A
– desmosome; B – nexus; C – tight junction; D – synapse; E – lateral interdigitations.
8. Each of the following statements concerning the mitochondria is true, EXCEPT:
A
– have a double-membrane structure; B – its inner membrane infolds to form cristae; C –
its matrix contains enzymes of Krebs’ cycle; D – its cristae contain enzymes of the
electron-transport chain; E
– are not able to produce ATP.
9. The cytoplasm basophilia is inherent in cells that:
A
– have cilia; B – accumulate lipids; C – actively synthesize proteins; D – accumulate
glycogen; E
– synthesize mucus.
10. The microfilaments are composed of the following proteins:
A
– actin; B – desmin; C – keratin; D – vimentin; E – integrin.
11. These filaments belong to the population of intermediate filaments, EXCEPT:
A
– tonofilaments; B – neurofilaments; C – actin filaments; D – glial filaments; E – desmin
filaments.
12. Each of the following statements concerning the nuclear envelope structure is
true, EXCEPT:
A
– consists of two membranes separated by the perinuclear space; B – contains nuclear
pores providing communication between the nucleus and cytoplasm; C
– its outer
membrane is studded with ribosomes; D
– its inner membrane has a fibrous lamina
anchoring chromatin; E
– its outer membrane is continuous with Golgi apparatus.
13. Each of the following statements concerning chromatin is true, EXCEPT:
A
– euchromatin is a lightly stained and dispersed; B – heterochromatin is a densely
stained and condensed; C
– heterochromatin takes part in transcription; D – two types of