1-2 Anatomy Flashcards
1
Q
FRONT (QUESTION)
A
BACK (ANSWER)
2
Q
Which stain is used in histology that binds to acidic structures and appears blue?
A
Hematoxylin
3
Q
What is the shortest distance at which two points can be seen as separate called in microscopy?
A
Resolving power
4
Q
What is the most commonly used fixative in the preparation of histologic specimens?
A
10% formaldehyde
5
Q
Which type of electron microscope provides a 3-dimensional view of a structure or cell?
A
Scanning Electron Microscope (SEM)
6
Q
Identify the step in histologic specimen preparation where xylene is generally used.
A
Clearing
7
Q
What is the name of the red acid dye that binds to basic structures in histologic staining?
A
Eosin
8
Q
Which process involves the use of protein coagulants or cross-linking agents to allow maximum preservation of structures?
A
Fixation
9
Q
What process follows fixation and involves running tissue samples through a series of increasing concentrations of organic solvent?
A
Dehydration
10
Q
What is the name of the stain that colors glycogen and carbohydrate-rich molecules magenta?
A
Periodic Acid-Schiff (PAS) Stain
11
Q
Name the step in histologic specimen preparation that involves placing the specimen on a slide warmer.
A
Mounting
12
Q
What heavy metal is typically used to coat a specimen in scanning electron microscopy (SEM)?
A
Gold or Palladium
13
Q
Identify the acid dye used to color reticular fibers black in histological staining.
A
Silver Stain
14
Q
What material is used to wipe the surface of the glass slide during mounting?
A
Egg albumin
15
Q
It is where the specimen is placed to facilitate drying and ensure specimen remains flat on slide during mounting.
A
Slide warmer
16
Q
Name the process in histology where tissue is made firm enough to allow very thin slices to be made.
A
Embedding
17
Q
Which part of the light microscope magnifies the image from the objective lens?
A
Ocular Lens or Eyepiece
18
Q
Which type of electron microscope produces a negative image on electron-sensitive film?
A
Transmission Electron Microscope (TEM)
19
Q
Name the step in preparing histologic specimens that follows embedding, involving the trimming and slicing of the paraffin-embedded tissue.
A
Sectioning
20
Q
Name the branch of anatomy that deals with the macroscopic morphology of the human body as seen with the naked eye.
A
Gross Anatomy
21
Q
Which structure in a cell is typically stained blue by hematoxylin due to its acidic nature?
A
Nucleus
22
Q
This step in preparing histologic specimens aims to facilitate drying and to make sure that the specimens remain flat on the slide.
A
Mounting
23
Q
HPO is used under 10x Eyepiece lens microscope. What is the total magnification?
A
400x Total Magnification (Formula: Magnification of Objective Lens x Magnification of Eyepiece)
24
Q
Which objective lenses are only used when studying very minute parts of specimens like individual cells or parts of cells?
A
HPO and OIO
25
What happens when a sample is viewed beyond the resolving power of the microscope?
empty magnification; no essential details can be viewed further
26
Enumerate: types of micrscopes
light micrscope: compound light microscope; electron microscope: transmission electron microscope, scanning electron microscope
27
Why is the light micrcoscope considered a compound microscope?
it uses several lenses to magnify an image
28
How is an image formed using the light microscope?
light beam is focuses > passes thorugh the specimen > enters objective lens > magnified by ocular lens
29
Enumerate: 4 objective lenses and its respective magnifications
scanning: 4x
low power: 10x
high power: 40x
oil immersion: 100x
30
Enumerate: types of ocular lenses
monocular
binocular
31
How is the total magnification identified?
magnification of objective lens x eyepiece
32
True or false: biological specimens are inherently of high contrast hence staining allows easier identification of parts
false: low contrast
33
Identify the stain used in this photomicrograph
hematoxylin and eosin
34
Identify the stain used in this photomicrograph
periodic acid schiff
35
Identify the stain used in this photomicrograph
best's carmine stain
36
Identify the stain used in this photomicrograph
silver stain
37
In order: what are the steps in preparation of histologic specimens using the he&e stain?
1. obtaining the specimen
2. fixation
3. dehydration
4. clearing
5. embedding
6. sectioning
7. mounting
8. deparaffinization and staining
38
Enumerate: two main types of electron microscope
tranmission electron microscope
scanning electron microscope
39
What are the important components used per step in preparing histolgoic specimens?
Obtaining the specimen: tissue sample near time of removal/de4th
Fixation: 10% buffered formalin/ 10% formaldehyde
Dehydration: organic solven (ethanol)
Clearing: xylene
Embedding: melted paraffin
Sectioning: specimen, paraffin, water bath
Mounting: egg albumin
Deparafinization and stianing: xylol, stain
40
What is the basic morphological and functional unit of all living things?
Cell
41
It is capable of independent existence as long as its environmental conditions are favorable.
Cell
42
What type of organism pertains to macroscopic organisms including humans?
Unicellular Organisms
43
This results from the union of the male gamete (sperm cell; spermatozoon) and the female gamete (ovum).
Zygote (fertilized ovum)
44
What is the multiplication of the fertilized ovum and the differentiation of its progenies eventually giving rise to an extremely complex organism?
Mitosis
45
What are the cells that perform the same general functions and are linked together by some amount of intercellular material and/or cell-to-cell junctions?
Tissues
46
What do you call the tissues, in varying portions, that bond together to form more complex functional structures?
Organ
47
Organs that have interrelated functions grouped together are called _______.
Organ System
48
Give at least 8 components of the cell.
Cell membrane (cm), Mitochondria (mi), Microvilli (mv), Smooth endoplasmic reticulum (sER), Ribosomes (ri), Rough endoplasmic reticulum (rER), Nucleus (ne), Nucleolus (nu), Chromatin (ch), Peroxisome (pe), Golgi complex (Gc), Lysosomes (ly), Centrosome (cs), Centrioles (ce), & Protein (pr)
49
What are the variations in the morphology of cells?
Neuron, Neutrophil, Hepatocytes, Oocyte, & Skeletal Muscles
50
Cells of the body vary in (1)______, (2)______, and (3)______, not only among the different cell types but also among cells of the same cells.
Size, Shape, Form
51
Because of the white morphological variations, human cells, and other eukaryotic cells do not share common basic structures. (true/false)
FALSE. They share common basic structures despite white morphological variations.
52
Cells consist of mass of cytoplasm, encased by cell membrane, and a nucleolus, a structure that is encased by a nuclear envelope embedded in the cytoplasm. (true/false)
FALSE. Nucleolus must be nucleus.
53
Cells vary by function or activity. (true/false)
TRUE
54
Cell membranes merely serve as an envelope that delimits the cells from their surroundings.
FALSE. The cell membrane provides various functions for the cell and the body.
55
What are cell membranes mainly made up of?
Phospholipids, Protein molecules, Cholesterol, & Polysaccharides
56
What is the typical size of a cell membrane?
8-10 nm
57
What do you call the structure of the cell membrane?
Trilaminar
58
What is a trilaminar structure?
An electron-lucent line sandwiched by two electron-dense layers.
59
Give at least 3 functions of a cell membrane.
- Protects the cell
- Delimits the cell from its surroundings
- It determines which substance can move in and out of the cell and it regulates the movement of these substances.
- It provides attachment for the skeleton of the cells
- Provides binding sites for the receptors for enzymes and other substances
- Allow cell to cell recognition
- In many cell types, it forms specialized junctions with the cell membrane of adjacent cells or the extracellular matrix.
60
What are the 3 parts of a phospholipid molecule?
1 head & 2 tails
61
What part of the phospholipid molecule is globular, polar, and hydrophilic, and consists of a gylycerol?
Head
62
What part of the phospholipid molecule is slender, non-polar, and hydrophobic?
Tail
63
What type of bonds link the fatty acids to the head?
Covalent bonds
64
What region of the phospholipid bilayer does the tail occupy?
Inner region
65
True or false, the tail is the electron-dense region that we can observe using the TEM
False, electron-lucent
66
The phospholipid molecules layered in what way to form the phospholipid bilayer?
closely opposed layers
67
True or false, the phospholipid bilayer allows water, gases, and few polar molecules to pass freely.
False, non-polar molecules
68
What accounts for 1/2 the total mass of the cell membrane?
Protein molecules
69
True or false, all transmembrane proteins are integral proteins, but not all integral proteins are transmembrane proteins.
TRUE
70
Thse type of proteins are loosely bound to the outer or inner surface of the membrane
Peripheral Proteins
71
List the four Membrane protein functions
Transport of substances, Enzymatic activity, Signal transduction and Cell to cell recognition
72
These molecules help in decreasing the cell's permeability to water-soluble substances.
Cholesterol
73
Where are Cholesterol molecules usually found?
In between spaces of phospholipid molecules
74
What forms do polysaccharides mostly take within the membrane?
glycolipid and glycoprotein
75
Thi is a thin layer of amorphous electron-dense material, that allows for cell-to-cell recognition, cell-to-cell adhesion and immunological response,
Glycocalyx
76
The thickness of the trilaminar entity depends on?
The amount of protein content
77
True or false, the cell membrane is not a unit membrane.
FALSE
78
Where can we find the specialized junctions formed by the cell membrane?
in localized regions of the cell membrane that are in contact with other with other cells or the extracellular matrix (ECM)
79
What term do we use to discribe the fingerlike cytoplasmic processes that allow for cell-to-cell attachments?
interdigitation
80
Identify the two types of junctional complexes that cells form with neighboring cells or with the extracellular matrix.
Occluding and Adhesive
81
This term refers to tight junctions or closing belt
Zonula occludens
82
List the several types of adhesive junctions
Zonula adherens, Fascia adherens, desmosome, and hemidesmosome
83
What do you call the junctions that enable the cells to communicate with each other?
Gap junction
84
What is the folded structure in the inner membrane of the mitochondria?
Cristae
85
In the endoplasmic reticulum, the rough and smooth ERs are differentiated by attached structures. What are these attached substances?
Ribosomes
86
True or False. The higher the viscosity of the cytoplasmic matrix, the lower the number of fibrillar elements.
FALSE
87
What's wrong in this statement. All mitochondria in all cells of the body originate from the sperm cells as mother's eggs do not contribute to the cytoplasmic component in the formation of zygote.
Sperm cells and mother's eggs are interchanged. All mitochondria in all cells of the body originate from the MOTHERS EGGS.
88
Which of the following form the supporting framework that maintains the shape and internal organization of the cell? A. Cytosol B. Incusions C. Fibrillar elements D. Organelles
c. Fibrillar Elements
89
It is the principal source of energy for various metabolic processed of the cell.
Adenosine Triphosphate (ATP)
90
What DNA can only be found outside the nucleus? A. Perosixmal B. Ribosomal C. Lysosomal D. Mitochondrial
D. Mitochondrial
91
Who is our lecturer on the cell?
Dr. S. Remulla
92
Ribosomes are sites for what synthesis?
Protein synthesis
93
It is the most extensive membrane-bound structure in the cytoplasm.
Endoplasmic Reticulum
94
Aside from lens fibers, what other cell is devoid of organelles? A. Mature WBC B. Immature WBC C. Mature RBC D. Immature RBC
C. Mature RBC
95
Ribosomes are produced in what part of the cell?
Nucleolus
96
Which RNA type is responsible for the connection of clusters of ribosomes? A. tRNA B. mRNA C. rRNA
B. mRNA
97
What makes the surface of the rough ER rough?
Presence of ribosomes and polyribosomes
98
Identify whether the given function is performed by the rough ER or the smooth ER: Protein processing and transport to Golgi complex
Rough ER
99
Identify whether the given function is performed by the rough ER or the smooth ER: Lipid synthesis
Smooth ER
100
Identify whether the given function is performed by the rough ER or the smooth ER: detoxification
Smooth ER
101
Identify whether the given function is performed by the rough ER or the smooth ER: carbohydrate metabolism
Smooth ER
102
This type of ER has more cisternae and vesicles
Rough ER
103
Smooth ER has _____ with few cisternae and vesicles
tubules
104
Which is more extensive in most cells? rough ER or smooth ER?
Rough ER
105
What is the function of hepatocytes as specialized form of smooth ER?
detoxification
106
What is the function of muscle cells as specialized form of smooth ER?
sarcoplasmic reticulum for calcium storage
107
It is a dynamic organelle capable of remodeling, disassembly, and assembly, and interaction with other organelles.
Endoplasmic Reticulum
108
It is an organelle several layers of membrane-bound, smooth-surfaced, and flattened tubes (cisternae) that are stacked on top of each other in a semicircular manner.
Golgi complex
109
TRUE OR FALSE. Golgi complex is membrane-bound.
TRUE
110
rounded dilatations (vesicles) on their lateral ends and their cavities are filled with fluid
Cisternae
111
When viewed under LIGHT microscope, golgi complex appears as network of solid strands impregnated with ____ or _____
silver salts; osmium
112
TRUE OR FALSE: Golgi complex is distinguishable when H&E stains were used.
FALSE. Not distinguishable.
113
It is the resulting image of Golgi complex in H&E preparations were used.
Negative golgi complex
114
It is pale region adjacent to the nucleus in cells with intensely basophilic cytoplasm
Negative golgi complex
115
The cytoplasm of golgi complex is _____ during H&E preparation
basophilic
116
TRUE OR FALSE: Golgi complex is distinguishable under electron microscope.
TRUE
117
What are the two faces of golgi complex
cis and trans face
118
It is the convex surface of the golgi complex
cis face
119
Other term for cis face
forming face
120
It is the face wherein it acts as the receiver of the transfer vesicles from the ER
cis face
121
Other term for trans face
maturing face
122
It is the type of vesicle that is pinched off from the trans (maturing) face.
secretory vesicle
123
This contains chemical containing pouches that float freely in the cytoplasmic matrix
Lysosomes
124
The hydrolytic enzymes of the lysosomes are from?
Golgi complex
125
TRUE OR FALSE: Lysosomes are distinguishable by histochemical methods that identify their hydrolytic enzymes
TRUE
126
Lysosomes are active at what pH level?
5
127
Lysosomes are inactive at what pH level?
7.2
128
Lysosomal enzymes of osteoclasts were released INTRAcelullarly or EXTRAcellularly?
Extracellularly
129
Where do lysosomal enzymes come from?
Golgi complex
130
TRUE OR FALSE: Lysosomes can be distinguished in H&E preparations
FALSE. Indistinguishable under H&E
131
It is the type digestion of foreign substances brought into the cell via phagocytosis
Heterophagy
132
It is the type digestion of the cell's own unneeded structures
Autophagy
133
It is the process of engulfing materials
Phagocytosis
134
cells capable of phagocytosis are referred to as?
phagocytes
135
This term refers the protrusions of the membrane at the binding site during phagocytosis
pseudopodia
136
resulting membrane-bound structure in phagocytosis
phagosome
137
It is the first organelle that detects the phagosome
primary lysosome
138
hydrolytic enzymes of the primary lysosome mixed with the digested material results to?
secondary lysosome
139
other term for secondary lysosome
phagolysome
140
Residual bodies in phagocytsosi can be removed in the cells through?
Exocytosis
141
Residual bodies accumulate in lipofuschin stain as?
lipochrome
142
It is an organelle that is membrane-bound spherical bodies that contain oxidases and hydrolases
Peroxisome
143
YES OR NO: Is peroxisome membrane-bound?
Yes
144
This aids in the detoxification and catabolism of various substances and some can result to hydrogen peroxide
Oxidases
145
Cells use the _____ in their peroxisomes to catalyze the conversion of hydrogen peroxide into oxygen and water
catalase
146
This enzyme prevents cytotoxic effects of hydrogen peroxide
catalase
147
The enzyme of peroxisome came from?
free ribosomes
148
The enzyme of lysosome came from?
Golgi complex
149
It is referred as the microtubule organizing center (MTOC)
centrosome
150
Centrosome is made up by:
2 centrioles and centriolar satellite
151
The two centrioles are collectively called as?
diplosome
152
Centrioles are surrounded by granular structures made up of protein called
centriolar satellite
153
It is the site of microtubule assembly and production
centrosome
154
What are the structures that were derived from the centrosome?
psyllium and flagella
155
It is a tubular structure made of electron-dense wall surrounding an electron-lucent space
centrioles
156
The wall of centrioles is made up of how many groups of microtubules?
9
157
Each group (triplet) of centrioles consist _____ microtubules.
3
158
What structure connects the innermost microtubule of a triplet is to the outermost microtubule of the adjacent triplet of microtubules?
fine filaments
159
centrioles are sources of?
mitotic spindles, cilia, and flagellum
160
Do centrioles divide or bud?
Bud
161
The _____ pull the sister chromatids apart during mitosis and disappears during telophase
mitotic spindles
162
It means affinity to basic dye.
Basophilic
163
It means affinity to acidic dye.
Acidophilic or Eosinophilic
164
A type of microscope that uses the electrons that has been transmitted through the specimen.
Transmission Electron Microscope
165
In this type of microscope, it gathers the electrons that has bounced off the specimen.
Scanning Electron Microscope
166
Among the 2 types of electron microscope, which type has a greater resolving power?
Transmission Electron Microscope
167
Give the stains that give off magenta or red color when in contact with glycogen.
Periodic Acid Schiff stain and Best Carmine stain
168
Generally temporary and inert structures found in cells of variable size, shape, and content
Cytoplasmic inclusions
169
There are cell types that contain ALL kinds of inclusions. (True or False)
FALSE (No cell contains all types of inclusions)
170
The kind and number of cytoplasmic inclusions present in a cell depend on __ and __.
Cell function; cell state of activity
171
Type of cytoplasmic inclusion present in adipose cells
Fat/lipid droplets
172
Lipid droplets are membrane-bound in the cell. (True or False)
FALSE (NOT membrane-bound)
173
Lipid droplets are __ (extracted, preserved) in routine histologic preparations but __ (extracted, preserved) after treatment with glutaraldehyde and osmic acid.
extracted; preserved
174
In __ cells, the nucleus is pushed to the periphery due to the large amount of stored lipids.
Adipose
175
Type of cytoplasmic inclusion that is the storage form of carbohydrates
Glycogen
176
Glycogen is an inclusion mainly abundant in __ and __ cells.
liver; muscle
177
The __ method of histologic preparation allows glycogen to be visible as purple/magenta granules.
Periodic-Acid Schiff (PAS)
178
Glycogen granules are NOT membrane-bound. (True or False)
TRUE
179
As seen in electron micrographs, __ particles refer to the electron-dense glycogen granules that are 90 nm in diameter while __ particles are those that are 20-30 nm in diameter.
Large/alpha; small/beta
180
Proteins from the Golgi complex to be released extracellularly via exocytosis; also known as secretory granules
Zymogen granules
181
Zymogen granules are characteristic of ___ cells.
Secretory epithelial
182
Zymogen granules are NOT membrane-bound. (True or False)
FALSE (Are membrane-bound)
183
The three most common types of pigment granules
Melanin; hemosiderin; lipofuschin/lipochrome
184
Pigment granules that appear yellowish-brown; are of coalesced residual bodies common in long-lived cells
Lipochrome/lipofuschin
185
Pigment granules that appear brown in color; pigment produced from the lysosomal digestion of hemoglobin
Hemosiderin
186
Pigment granules responsible for brown to black coloration of the skin
Melanin
187
Melanin is present in __, __, __, and __.
Skin; nerve cells of substantia nigra; locus coeruleus of brain; pigment epithelium of retinas
188
Melanin is produced by __ then transferred to __ for storage.
Melanocytes; keratinocytes
189
In a photomicrograph, melanocytes are readily distinguishable from keratinocytes due to what unique feature?
Clear area/space surrounding the melanocytes
190
Residual bodies are NOT membrane-bound. (True or False)
FALSE (Are membrane-bound)
191
Hemosiderin is made distinguishable from other pigments via what staining method?
Prussian blue staining
192
The iron-containing pigment responsible for the color of red blood cells
Hemoglobin
193
Give an organ which may have cells in which hemosiderin can be observed.
Spleen
194
What component of hemosiderin allows it to be distinguishable from other pigments via special staining?
Iron
195
Give two examples of cells that may contain lipofuschin granules.
Myocardial muscle cells; Sertoli cells in testes
196
Cytoplasmic inclusions present in very few cell types and of unknown exact chemical composition and functions
Crystals
197
Crystals are most often __-shaped.
rod
198
Crystals are thought to be __ products as they are more common in cells of older individuals.
degenerative
199
Crystals are NOT membrane-bound. (True or False)
TRUE
200
Give the two cell types in which crystals can be found.
Leydig cells; Sertoli cells
201
Dust particles are membrane-bound. (True or False)
TRUE
202
Dust particles are numerous in the cytoplasm of phagocytes of the lungs, specifically ___ and ___.
Pulmonary alveolar macrophages; dust cells
203
What type of materials make up dust particles?
Exogenous
204
What is the color of the structures of dust particles?
Brown to black
205
What is the complex network of fibrillar elements that forms the structural framework or skeleton of the cell?
Cytoskeleton
206
Fibrillar elements of the cytoskeleton can only be demonstrated with the aid of ___ and ___.
Special histologic techniques; electron microscopy
207
The cytoskeleton is mainly involved in ___ and ___.
Movement of organelles and cellular structures; changes in cell shape
208
Microfilaments are only present in some cells. (True or False)
FALSE (Present in ALL)
209
Microfilaments are abundant in ___ areas of most cells.
Peripheral
210
Microfilaments are organized to form an interconnecting network and are involved in activities occurring in the cell membrane such as ___ and ___.
Exocytosis; endocytosis
211
Microfilaments are made up of ___.
F-actin (filamentous actin)
212
Actin comprises ___ of the total protein in cells.
10% to 15%
213
Half of the actin in cells exists as F-actin while the rest exists as ___.
G-actin (globular actin)
214
How is F-actin formed?
Coiling of two G-actin strands
215
Why do microfilaments undergo quick and frequent assembly and disassembly?
To accommodate changes of cell shape and cell movement
216
Give at least 3 functions of microfilaments.
- Provide internal support
- Involved in exocytosis and endocytosis
- Involved in the movement of cell organelles
- Involved in contraction (e.g., muscle cells and myoepithelial cells)
- Play a role in cell locomotion
217
Microfilaments are less in number and serve as a supportive element in the ___ area of the cell.
Central
218
Microfilaments are scattered haphazardly in the central area of the cell. (True or False)
TRUE
219
In the cell, intermediate filaments are found in ___ and ___.
Cytoplasm; nucleus
220
Compared to microfilaments and microtubules, their size is ___ the two.
Between / Intermediate
221
Give at least 3 intermediate filaments in the cytoplasm that are morphologically similar but different in protein contents.
- Keratin
- Desmin
- Vimentin
- Neurofilament
- Glial filament
222
What are the intermediate filaments found in the nucleus?
Lamins (A and B)
223
Keratin filaments are only present in ___, especially in ___ or the main cell type in the epidermis.
Epithelial cells; keratinocytes
224
Why does the biochemical composition of keratin filaments vary depending on cell type?
Due to several types of keratin subunits
225
The primary function of keratin filaments is ___, but they are also involved in ___.
Protecting epithelial cells from mechanical and non-mechanical stresses; cell-to-cell attachment
226
Desmin is also known as ___.
Skeletin filaments
227
Desmin is more numerous in what type of muscle cells?
Smooth muscles
228
Desmin filaments help maintain muscle cell architecture and structure by ___.
Connecting or anchoring many cytoplasmic components
229
Vimentin filaments are present in what type of cells?
Cells that differentiate from the mesenchyme (e.g., fibroblasts and muscle cells)
230
What are the functions of vimentin?
- Maintains cell shape and integrity of the cytoplasm
- Stabilizes cytoskeletal interactions
- Provides support and anchor cytoplasmic organelles
231
Neurofilaments are present in the ___ and ___ of neurons.
Cell body; all the processes
232
In the processes of neurons, neurofilaments run ___ to the long axis of processes.
Parallel
233
What is the main function of neurofilaments?
Providing internal support to the neurons
234
What are glial filaments also known as?
Glial fibrillary acidic protein (GFA)
235
Where are glial filaments found?
Glial or neuroglial cells
236
Lamins A and B are part of the nuclear lamina (fibrous lamina). (True or False)
TRUE
237
Lamins A and B function in ___ and ___.
- Helping maintain the shape of nucleus
- Anchoring the nucleus to the ER
238
Microtubules are ___ than microfilaments and intermediate filaments.
Thicker
239
Microtubules can be assembled and disassembled quickly. (True or False)
TRUE
240
Microtubules are hollow tubules with walls formed by ___.
13 tubulin molecules
241
___ surround microtubules to strengthen and stabilize their walls.
Microtubule-associated proteins (MAPs)
242
How are microtubules formed?
Polymerization of alpha-tubulin and beta-tubulin
243
Where are microtubules formed?
Centrosome or microtubule organizing center (MTOC)
244
What are the functions of microtubules?
- Play a role in the movement of attached organelles within the cytoplasm
- Provide internal support to the cell
245
Give examples of organelles and structures with walls that are comprised of microtubules.
- Centrioles
- Mitotic spindles (during mitosis and meiosis)
- Core (axenome) of cilia
- Flagellum (tail) of the sperm cell (spermatozoon)
246
What is the largest structure inside the cell?
Nucleus
247
What type of nucleus do neutrophils have?
Multi-lobar
248
The nucleus exists in almost all cells except ___ and ___.
Red blood cells (RBCs), Lens fibers of the eyes
249
Most cells are uninucleated and only some are multinucleated. Give an example of cells with more than one nucleus.
Osteoclasts
250
What structure delimits the nucleus from the cytoplasmic matrix?
Nuclear envelope/membrane
251
What is the substance that fills the interior of the nucleus?
Nuclear matrix/Nucleoplasm (also karyolymph or nuclear sap)
252
The nucleoplasm has a similar composition with the ___.
Cytosol (fluid part of the cytoplasm)
253
What structures are embedded in the nucleoplasm?
Chromosomes
254
At interphase, these structures are embedded in the nuclear matrix.
Chromatin, one or more nucleoli
255
This structure embedded within the nucleus is only visible during interphase.
Nucleolus
256
These are "codes" that produce nucleic acids and proteins.
Genes
257
In what structure within the nucleus are genes stored?
Chromosomes
258
Why is the nucleus considered as the data bank of the cell?
It houses chromosomes where genes are stored
259
What structure inside the nucleus serves as the site for RNA synthesis?
Nucleolus (produce mRNA, tRNA, rRNA)
260
The nuclear envelope/membrane has a single unit membrane. (True or False)
FALSE (it has 2, an inner and an outer membrane)
261
Which portion of the nuclear envelope is continuous with the ER?
Outer nuclear membrane
262
Which portion of the nuclear envelope is closely associated with the nuclear lamina?
Inner nuclear membrane
263
It is a fluid-filled space that separates the outer and inner nuclear membranes.
Perinuclear space (also intermembranous space or perinuclear cisterna)
264
Each individual membrane of the nuclear envelope is thicker than the perinuclear space. (True or False)
FALSE (each membrane is 7 to 8 nm thick while the perinuclear space is 10 to 30 nm thick)
265
This structure is made up of lamins, nuclear intermediate filaments, and nuclear lamin-associated membrane proteins.
Nuclear lamina (also fibrous lamina)
266
Clumps of RNA are attached to the nuclear lamina. (True or False)
FALSE (chromatin is not RNA)
267
These are hundreds to thousands of circular openings that perforate the nuclear envelope.
Nuclear pores
268
What structure stabilizes the nuclear pores?
Nuclear lamina (also fibrous lamina)
269
What structure surrounds each nuclear pore?
Nuclear pore complex
270
What structure covers the nuclear pore as a thin film?
Pore diaphragm
271
Aside from providing a mechanical support for the nucleus, what are the other functions of the nuclear lamina?
- Chromatin organization (since chromatin are attached)
- Cell cycle regulation
- DNA replication and repair
- Cell differentiation
- Apoptosis (programmed cell death)
- Exchange of substances between the nucleus and the cytoplasm
272
Highly condensed form of chromatin
Chromosomes
273
How many somatic pairs of chromosomes do humans have?
22
274
How many pairs of sex chromosomes do humans have?
1
275
How many chromosomes are present in diploid cells?
46
276
The removal of the nucleus in nucleated cells can lead to ___.
Cell death
277
This structure is too thin to be appreciated under the optical microscope but can be seen under EM.
Nuclear envelope
278
In males, somatic and sex chromosomes are homologous. (True or False)
FALSE
279
Female sex chromosomes have a shorter Y chromosome. (True or False)
FALSE
280
Give the two distinct dispersal patterns of chromatin.
Heterochromatin, euchromatin
281
Portions of chromosomes actively producing RNAs
Euchromatin
282
The human genome consists of the total amount of DNA present in the chromosomes only. (True or False)
FALSE
283
Pale areas in the nucleus that do not take up stains
Euchromatin
284
Nitrogenous bases are paired by what type of bond?
Hydrogen bonds
285
Only about __% of the DNA molecules in the chromosomes encode for genes.
5
286
In the human chromosomal genome, there are ___ nitrogen-containing bases arranged in a specific order.
3 billion
287
Give the three components of a DNA molecule.
Deoxyribose (sugar), phosphate groups, pair of nitrogenous bases
288
This structure is a filamentous protein network in the interphase nucleus that is anchored on the fibrous lamina.
Nuclear scaffold
289
Large and small ribosomal subunits find their way to the cytoplasm together via nuclear pores. (True or False)
FALSE
290
The nucleolus is absent in cells that produce very little to no proteins. (True or False)
TRUE
291
The grainy area in the nucleolus
Pars granulosa
292
The nucleolus is not membrane-bound. (True or False)
TRUE
293
What is the function of the nucleolus?
To produce ribosomal units
294
The nucleolus is present during interphase and late anaphase. (True or False)
FALSE
295
The electron-dense area formed by rRNA molecules produced in the nucleolar organizing region
Pars fibrosa
296
An rRNA molecule linked to proteins from the cytoplasm is called ___.
Ribonucleoprotein or ribosomal subunits
297
The number of nucleolus in hepatocytes
2 or more
298
There are ___ pairs of chromosomes with nucleolar organizers in humans.
5
299
Area where chromosomes containing nuclear organizers (genes that code for rRNA) gather then transcribe and produce rRNA
Nucleolar organizing region
300
This is formed when rRNA from the pars fibrosa and imported proteins from the cytoplasm get linked together.
Pars granulosa
301
What is the bond between protein monomers called?
Peptide bond
302
What are the monomers that make up proteins?
Amino acids
303
Two types of protein can have the same amino acid sequence. (True or False)
FALSE
304
Type of protein that catalyzes biochemical reactions
Enzymes
305
What is the process of assembling amino acids into new polypeptide chains?
Protein synthesis
306
Essential amino acids are synthesized by the cells. (True or False)
FALSE
307
Essential amino acids are obtained from ingested food. (True or False)
TRUE
308
In the nucleus, the DNA sequence is first transcribed into what?
Pre-mRNA
309
What is the template for an mRNA?
DNA sequence
310
DNA: deoxyribose; RNA: ___?
Ribose
311
In transcription, Guanine pairs with ___ while Adenine pairs with ___?
Cytosine; Uracil
312
The genetic material produced after post-transcriptional modification
mRNA
313
What is the significant sequence of 3 adjacent bases in mRNA called?
Codon
314
Each amino acid has only one codon. (True or False)
FALSE
315
Each codon represents only one amino acid. (True or False)
TRUE
316
Where does tRNA transcription occur?
Nucleus
317
What is the trinucleotide sequence located at one end of the tRNA?
Anticodon
318
It translates the mRNA code into polypeptide chains.
Ribosome
319
What is the start codon and its corresponding amino acid?
AUG, Methionine
320
It signals the ribosome to end the process of protein synthesis.
Stop codon (i.e., UAG, UAA, UGA)
321
More than one ribosome can translate an mRNA at the same time. (True or False)
TRUE
322
What is an mRNA with multiple ribosomes called?
Polyribosome
323
Proteins from free ribosomes are exported out of the cell through exocytosis. (True or False)
FALSE
324
Proteins from attached ribosomes can be used by the cell or exported out of the cell. (True or False)
TRUE
325
What are the small membrane-bound vesicles released by the rER towards the Golgi complex?
Transfer vesicles
326
The transfer vesicles arrive at which part of the Golgi complex?
Forming face/cis face
327
The form in which proteins are released from the maturing face of the Golgi complex
Secretory vesicles
328
What is the process of transporting secretory products out of the cell?
Exocytosis
329
The cell membrane is a semipermeable membrane that allows all materials to enter and exit the cell. (True or False)
FALSE
330
The taking in of large solid substances into the cell
Phagocytosis
331
The taking in of fluids into the cell
Pinocytosis
332
Exocytosis which requires a signal for releasing secretory materials out of the cell
Regulated Secretion
333
Exocytosis which requires no signals for releasing secretory materials out of the cell
Constitutive Secretion
334
What is the bulk transport of substances that pass through the cell and released at the opposite cell surface?
Transcytosis
335
A ___ is capable of independent existence as long as its environmental conditions are favorable
cell
336
All living things are multicellular. (True or False)
FALSE
337
Integral proteins can either be attached inside or outside the cell membrane. (True or False)
FALSE (peripheral proteins)
338
Polysaccharides in the membrane are mostly in the form of ___ and ___.
glycolipid, glycoprotein
339
What is the term for the cell coat formed by the projection of glycolipid and glycoprotein from the outer surface of the cell membrane?
glycocalyx
340
Similar to the cell membrane, a unit membrane is made up of ___.
phospholipid molecules
341
What are the structures enclosed by a unit membrane?
peroxisomes, lysosomes, endoplasmic reticulum, Golgi complex
342
Cytoplasm refers to the material within a living cell, excluding the nucleus. (True or False)
TRUE
343
What is the homogenous substance where various formed elements are embedded?
cytoplasmic matrix or cytosol
344
What are the formed elements embedded in the cytosol?
organelles, inclusions, cytoskeleton
345
Cytosol is viscid, translucent and colloidal in nature. (True or False)
TRUE
346
Cytosol is mostly made up of water wherein ___ and ___ are dissolved.
inorganic ions, organic molecules
347
What are the functions of the cytosol?
site of essential biochemical processes, environment for organelles in the performance of their functions
348
Organelles are present in all cells except in ___ and in ___.
RBCs and lens fiber
349
What organelles are not delimited by unit membranes?
ribosomes, centrosome
350
The wall of a mitochondrion encloses a cavity that is filled with matrix called ___.
intercristal space
351
The mitochondrion consists of a wall which has one layer. (True or False)
FALSE (it has two layers called outer and inner leaflets)
352
The inner membrane of the mitochondrion is folded to form the cristae that projects into the intercristal space. (True or False)
TRUE
353
Why are mitochondria called the "powerhouses" of the cell?
generates most of the cell's energy for performing metabollic processes, degradation process of the enzymes in the mitochondrial matrix yields a lot of ATP molecules
354
___ is the only DNA in the cells that is found outside the nucleus.
mitochondrial DNA
355
Why do all mitochondria in all cells of the body originate only from the female gametes?
male gametes do not contribute to the cytoplasmic component in zygote formation
356
What connects polyribosomes/polysomes together?
mRNA
357
What makes the cytoplasm basophilic?
increased number of ribosomes (numerous phosphate groups of the RNA in ribosomes)
358
Organelle made up of interconnecting tubules, vesicles, and sacs known as cisternae
endoplasmic reticulum
359
The ER is the most extensive membrane-bound structure in the cytoplasm. (True or False)
TRUE
360
It is the site of protein synthesis and it receives and processes the proteins from the attached ribosomes.
rough endoplasmic reticulum
361
It is the site of synthesis of lipids, phospholipids, cholesterol, and other steroids.
smooth endoplasmic reticulum
362
It is involved in the metabolism of carbohydrates and detoxification of substances like metabolic products and drugs.
smooth endoplasmic reticulum
363
It passes the proteins to the Golgi complex in the form of transfer vesicles.
rough endoplasmic reticulum
364
It plays a role in the transport of fatty acids and lipids.
smooth endoplasmic reticulum
365
These are pouches made of unit membranes and hydrolytic enzymes from the Golgi complex.
lysosomes
366
The chemicals in the lysosomes are hydrolytic enzymes bound by unit membranes. (True or False)
TRUE
367
What are the lysosomal enzymes?
proteases, lipases, carbohydrates, esterases, nucleases
368
The lysosomes can digest nearly all organic substances in the cell. (True or False)
TRUE
369
At what pH is the lysosome active and inactive?
active at pH = 5; inactive at pH = 7.2
370
What is the difference between heterophagy and autophagy?
Heterophagy - digestion of foreign substances brought into the cell via phagocytosis; Autophagy - digestion of the cell's own unneeded structures
371
What is the process of engulfing materials such as microorganisms and senescent red blood cells?
phagocytosis
372
All cells are capable of phagocytosis. (True or False)
FALSE
373
What is the term for cells that are capable of phagocytosis?
phagocytes
374
It releases lysosomal enzymes extracellularly and is responsible for bone resorption.
osteoclast
375
Pouches made of unit membranes and enzymes from the cytoplasmic matrix
peroxisomes
376
This enzyme is responsible for the detoxification and catabolism of various substances.
oxidases
377
This enzyme converts hydrogen peroxide to oxygen and water.
catalase
378
Hydrogen peroxide is converted into oxygen and water since it is poisonous to cells. (True or False)
TRUE
379
It is the microtubule organizing center (MTOC).
centrosome
380
Two centrioles are collectively called ___.
diplosome
381
Centrioles are cylindrical bodies that are surrounded by granular structures made up of protein called ___.
centriolar satellites
382
It is the site of microtubule assembly and production.
centrosome
383
It is a tubular structure consisting of an electron-dense wall of assembled microtubules surrounding an electron-lucent space.
centrioles
384
The wall of a centriole is made up of __ triplets of microtubules.
nine
385
Centrioles are sources of ___, ___, and ___.
mitotic spindles, cilia, flagellum
386
What connects the innermost microtubule of a triplet to the outermost microtubule of the adjacent triplet?
fine filaments
387
How do centrioles replicate?
Centrioles bud and grow out of the lateral surface on each centriole. The procentrioles elongate to form daughter cells and set perpendicularly to their mother cells. The mother-daughter centrioles make up a diplosome and acquire centriolar satellites to form a centrosome.
388
What is the ratio of melanocytes to keratinocytes?
1:10
389
Intermediate filaments are located in ___ and ___. Their size is usually in between that of microfilaments and microtubules, with a diameter of around ___ nm.
cytoplasm, nucleus, 10-12
390
Keratin filaments are only present in epithelial cells, especially in ___. Their primary function is to protect cells from mechanical and nonmechanical stresses.
keratinocytes
391
Neurofilaments are characteristic of nerve cells (neurons) and are present in the cell body and all the processes of neurons. They provide internal ___.
support
392
Microtubules are surrounded by ___ that strengthen and stabilize their walls.
microtubule-associated proteins (MAPs)
393
Tubulin refers to a small family of minute ____ proteins.
globular
394
The nucleus is bounded from the cytoplasmic matrix by a ____ envelope.
nuclear
395
Chromosomes are structures embedded in the nucleoplasm which are called ___ in the interphase stage.
chromatin
396
The nuclear envelope is also known as the ___.
nuclear membrane
397
The perinuclear space can be regarded as a specialized portion of the ___.
rough endoplasmic reticulum
398
The nuclear lamina provides mechanical support to the ___.
nucleus
399
The nuclear pore complex is stabilized by the ___.
nuclear lamina
400
The nuclear lamina is made of lamins, nuclear intermediate filaments, and nuclear lamin-associated membrane ___.
proteins
401
Chromosomes are the highly condensed form of ___.
chromatin
402
At interphase, chromosomes are stretched out into fine entangling threads termed as ___.
chromatin
403
Chromatin has 2 distinct dispersal patterns: extended areas (___) and condensed areas (___).
euchromatin, heterochromatin
404
The human genome contains the total amount of DNA present in the chromosomes and in the ___.
mitochondria
405
A DNA molecule resembles a very long twisted ladder made of deoxyribose, phosphate groups, and pairs of nitrogenous bases like adenine, thymine, cytosine, and ___.
guanine
406
In the human chromosomal genome, there are 3 billion nitrogen-containing bases arranged in a specific ___.
order
407
A gene is the segment of the DNA molecule that contains the unique sequence of base pairs for the production of a particular ___.
protein
408
The transport of secretory vesicles to release substances outside the cell
exocytosis
409
The engulfing of extracellular substances to bring them into the cell
endocytosis
410
This process allows endocytosed substances to cross the cell and be released at the opposite surface.
transcytosis
411
This transport allows molecules to move across the membrane without energy.
passive transport
412
This transport uses energy to move molecules across the membrane.
active transport
413
It provides pathways for ions to pass through.
ion channels
414
It uses carrier proteins to move molecules across.
carrier transport
415
The engulfing of solid substances to bring them into the cell
phagocytosis
416
The engulfing of liquid substances to bring them into the cell
pinocytosis
417
The engulfing of large amounts of liquid into the cell
macropinocytosis
418
The engulfing of minute amounts of liquid into the cell
micropinocytosis
419
This attacks the pinocytic vesicle to release its contents.
lysosome
