Histology Flashcards
1
Q
What is the inner cytosol?
A
The cytoplasm - half way between a gel and fluid
2
Q
What is the cytoskeleton?
And what is it made from?
A
A structure that determines the shape and fluidity of the cell made from thin and intermediate filaments and microtubules
3
Q
What are inclusions?
A
Nutrients or pigments within the cell that do not have activity. They may or may not be bound by a membrane.
4
Q
What is the plasmalemma?
A
The cell membrane which separates the cytoplasm from outside environment
5
Q
Structure of the plasmalemma
A
Bimolecular layer of amphipathic phospholipid molecules
6
Q
Chemical elements in hydrophilic heads
A
Choline and phosphate
7
Q
Chemical molecules in hydrophobic tails
A
Fatty acid chains and cholesterol
8
Q
Exocytosis
A
A form of active transport when the cell transports molecules out of the cell
9
Q
Endocytosis
A
A form of active transport when the cell transports molecules into the cell
10
Q
Molecules that are highly permeable through the cell membrane
A
Water, oxygen and small hydrophobic molecules
11
Q
Molecules that are not highly permeable through the cell membrane
A
Charged ions
12
Q
Mitochondria function
A
Energy production
13
Q
Rough endoplasmic reticulum function
A
Protein synthesis
14
Q
Smooth endoplasmic reticulum function
A
For cholesterol and lipid synthesis/detoxification
15
Q
Golgi apparatus function
A
For modification and packaging of secretions
16
Q
Lysosomes (hydrologic enzymes) function
A
For intravenously digestion
17
Q
Nucleus function
A
Contains genetic code
18
Q
Inclusions
A
Components that have been synthesised by the cell itself or taken up from extracellular environment
19
Q
Microfilaments are composed of?
A
Fine strands of the protein actin
20
Q
Diameter of microfilaments
A
7nm
21
Q
Intermediate filaments function
A
Bind intracellular elements together and to the plasmalemma
22
Q
Diameter of intermediate filaments
A
10-15nm
23
Q
Microtubles structure
A
Hollow tubules composed of two types of tubular subunits, alpha and beta
24
Q
Where do microtubles originate from?
A
The centrosome (MTOC)
25
Microtubles allow ... to produce motion
Cilia and flagella
26
Microtubles function
They serve as a motorway. Dynein and kinesin attach to the microtubles and move along them using ATP
27
Kinesin
An ATPase that moves towards the cell periphery
28
Dynein
An ATPase that moves towards the cell centre
29
What is the nucleus surround in?
A nuclear envelope (an inner and outer membrane)
30
Perinuclear cystern
Space between the inner and outer nuclear membrane
31
The nucleus is the region of
RNA synthesis
32
mRNA and tRNA are transcribed in what?
The nucleolus, a dense area within the nucleus
33
The nucleus contains two types of DNA, name them
Euchromatin and heterochromatin
34
Euchromatin is?
Partially unwound DNA undergoing transcription
35
Heterochromatin is?
Highly condensed DNA not undergoing transcription
36
Where are the ribosomes formed?
In the nucleolus
37
Ribosome function
Protein synthesis
38
What is each ribosome made up of?
A small subunit which binds to RNA and a large subunit which catalyses the formation of peptide bonds
39
Endoplasmic reticulum
Network of interconnecting membrane bound compartments in the cell
40
Rough endoplasmic reticulum appearance and role
Studded with ribosomes. Helps to synthesise proteins destined for insertion into membranes or for secretion
41
Smooth endoplasmic reticulum role
Continues the processing of proteins produced in the RER and has a vital role in the site of synthesis of lipids
42
What does the Golgi complex do?
Modifies and packaged macromolecules that were synthesised in the endoplasmic reticulum
43
What modifications can the Golgi apparatus make to macromolecules?
Add sugars and cleave some proteins
44
The mitochondria structure
It has an inner and outer membrane. The inner membrane is extensively folded to form cristae to increase surface area
45
Function of Mitochondria
Power generators of the cell which produce ATP and contain their own DNA
46
Occluding Junctions Function
They link cells to prevent diffusion and are a focal region of close opposition between adjacent cell membranes
47
Anchoring Junctions Role
Provide mechanical strength
48
Types of anchoring junctions
Adherent junctions and desmosomes
49
Adherent junctions
Link submembrane actin bundles of adjacent cells
50
Desmosomes
Link sub membrane intermediate filaments or adjacent cells (stronger)
51
Communicating junctions
Allow selective diffusions of molecules between adjacent cells
52
What do communicating junctions look like
Physical pores
53
What are the pores of communicating junctions produced by?
Connexion proteins
54
What are communicating junctions found in?
Smooth muscle, cardiac muscle and epithelial tissue
55
Exocytosis
A form of active transport when the cell transports molecules out of the cell and is often receptor mediated
56
Phagocytosis process
Bacteria or larger particle binds to the cell surface receptors triggering extensions of the cell to engulf it forming a phagosome. The phagosome binds to lysosomes carrying digestive enzymes producing a phagolysome
57
two types of stains common stains used to bind to certain types of molecules
eosin and haematoxylin
58
haematoxylin is a ----- dye with an affinity for ------- and stains them ----
basic, acidic molecules, purplish blue
| nucleus dna and ribosomes
59
eosin is a ------ dye with an affinity for ----- and stains them
acidic, basic, pink or red
60
epithelia can form ----- ------ and --
solid organs (liver) and glands
61
what is always found between epithelial cells and what purpose does this serve?
adhesions allows strong sheets to be formed
62
what is found at the basal surface of epithelial cells?
basal lamina
63
what is basal lamina?
layer of extracellular matrix secreted by the epithelial cells, on which the epithelium sits
64
are epithelia cells vascular or non-vascular?
non-vascular
65
how do nutrients from capillaries reach the basal lamina?
they must diffuse across the basal lamina
66
squamous cell shape
flattened
67
cuboidal cell shape
like a cube
68
columnar cell shape
like a column, tall and thin
69
simple. how many layers?
1
70
stratified. how many layers?
two or more layers
71
pseudostratified. how many layers?
1, looks like multiple layers but all cells are in contact with the basal lamina
72
what do glandular epithelia produce?
secretory products such as milk sweat oil hormones etc
73
where are secretory products secreted from?
endocrine glands and exocrine glands
74
endocrine glands. where are products secreted? ducts or ductless
products are secreted towards the basal end of the cell and are then distributed throughout the body. ductless.
75
exocrine glands. where are products secreted? ducts or ductless?
products are secreted towards the apical end of the cell either into the lumen of an internal space, into a duct, or onto the body surface. They are ducted glands
76
three categories of connective tissue
soft connective tissue, hard connective tissue and blood and lymph
77
soft connective tissue examples
tendons, ligaments, storm of organs, dermis of skin
78
hard connective tissue examples
bone and cartilage
79
what two components makes up connective tissue?
extracellular matrix and cells. the type of connective tissue is determined by the types and relatives amounts of these two components
80
what does the extracellular matrix consist of?
fibres (collagen, reticular and elastic fibres|) tissue fluid and ground substance
81
soft connective tissue: loose
loosely packed fibres separated by abundant ground substance. cells are relatively plentiful
82
soft connective tissue: dense
densely packed bundles of collagen fibres. can be dense regular or dense irregular
83
what causes the semi-rigid nature of the matrix
the highly hydrated nature of ground substance
84
how does cartilage receive nutrients
it receives it from adjacent tissues by diffusion through its matrix
85
three types of cartilage
hyaline, elastic and fibrocartilage
86
what defines the type of cartilage
the extracellular matrix
87
two types of hard connective tissue
cartilage and bone
88
type of bone that is the outer shell of dense cortical bone that makes up the shaft
diaphysis
89
type of bone that looks like a thin mesh and is at either end of the bone
cancellous or trabecular
90
the name of canals that penetrate bone
Haversian canals
91
role of Haversian canals
to allow nerves and blood vessels to run through bones
92
cells found living in bones are called
osteocytes
93
how is forced produced my muscle
the movement of actin fibres over myosin fibres with the aid of accessory proteins allows force to be produced
94
two other names for smooth muscle
involuntary or visceral
95
why is smooth muscle called smooth muscle
it has no visible ridges
96
why can smooth muscle be called visceral
because it is mostly found in organs
97
general shape of muscle fibres
elongated cells with a great range in length
98
what is found at the centre of each muscle fibre?
a cigar shaped nucleus
99
other names for skeletal muscle
voluntary or striated (ridged)
100
what do muscles of the body respond to?
conscious control
101
shape of skeletal muscle cells
Giant multinucleate cylindrical cells
102
nuclei within skeletal muscle fibres description
each fibre has many nuclei that are elongated and located at the periphery of the cell, just internal to the cell membrane
103
difference in cardiac muscle compared with striated muscle
the striations in cardiac muscle are less prominent and the fibres are much shorter
104
where is the nucleus located in cardiac muscle?
one singular nucleus located near the centre of the fibre
105
sites of end-to-end attachment in cardiac muscle between adjacent cells
intercalated discs
106
what does nervous tissue consist of?
neurons and support cells (glial cells)
107
are there more neurons or glial cells?
glial cells outnumber neurons
108
the surrounding connective tissue on nerves for the CNS
Meninges
109
the surrounding connective tissue on nerves for the PNS
Epineurium
110
multipolar neurons
they are the most commo, have many dendrites and only one axon
111
bipolar neurons
they have one dendrite and one axon
112
pseudounipolar
the axon is split into two branches, one branch runs to the spinal cord and the other runs to the periphery
113
three types of principle glial cells of CNS
astrocytes, microglia and oligondenrocyes
114
astrocytes
principle glial cell of CNS: support, ion transport, induce blood brain barrier
115
microglia
principle glial cell of CNS: provide immune surveillance
116
oligodendrocytes
principle glial cell of CNS: produce myelin in the brain and spinal cord
117
Schwann cells
principle glia of PNS; produce myelin and support axons
118
what are the four basic tissue types?
epithelium, connective tissue, muscle, nervous tissue
119
where is most fluid absorbed in the digestive tract?
in the small intestine
120
how much fluid reaches the colon?
about 1.5 litres
121
name the three main salivary glands
parotid, submandibular and sublingual glands
122
why does the pancreas not digest itself?
the enzymes are produced in an inactive form
123
what type of cartridge are tracheal rings?
hyaline cartilage
124
what is the difference between bronchi and bronchioles
bronchi are surrounded in cartilage and bronchioles are surrounded by smooth muscle
125
what are alveoli lined with?
simple squamous epithelium to provide the thinnest distance between blood and air
126
4 major layers of the digestive tract - lumen and going outwards
1. muscosa
2. submucosa
3. muscularis externa
4. serosa or adventitia
127
3 parts of the mucosa
a) epithelium: sits on a basal lamina
b) lamina propria: loose connective tissue
c) muscularis mucosae: thin layer of smooth muscle
128
what is submucosa, the 2nd inner layer of the digestive tract?
loose connective tissue
129
what is muscularis externa? the 3rd layer of the digestive tract
two thick layers of smooth muscle, an inner circular layer and an outer longitudinal layer
130
what is the serosa or adventitia? 4th layer of the digestive tract
an outer layer of connective tissue that either suspends the digestive tract or attaches to other organs
131
the name for the digestive tracts nervous system
the enteric nervous system
132
where does the enteric nervous system receive input from?
from the autonomic nervous system
133
what are ganglia?
groups of neurons between the two muscle layers that make up the muscularis externa (3rd layer of the digestive tract
134
four sections of the trachea from airway outwards
airway, respiratory epithelium, lamina propria, hyaline carolinge of tracheal ring
135
bronchi and bronchioles: which has the smaller airway?
bronchioles
136
bronchi and bronchioles: which has hyaline cartilage in their walls?
bronci
137
bronchi and bronchioles: which one has smooth muscle predominating their walls?
bronchioles
138
columnar cells of the epithelium get shorter the...
further down the respiratory tract you go
139
does gas exchange happen over the epithelia?
no
140
general arrangement of lobules
hexagonal arrangement
141
where are lobules found?
in the liver
142
what is found at each corner of the lobule?
a branch of the hepatic portal vein and hepatic artery
143
what do the hepatic portal vein and hepatic artery do?
deliver blood to the lobule
144
what is at the centre of a lobule?
central vein
145
where does the central vein drain to?
the hepatic vein
146
blood travelling from a corner of a lobule to the centre does so via what?
hepatic sinusoids
147
what are the sheets of liver called?
hepatocytes
148
what are the spaces for blood flow in the liver called?
sinusoids
149
combination of hepatic portal vein, bile duct and hepatic arteriole in the corner of a lobule is collectively called the...?
portal triad
150
why is the pancreases unusual?
it is both an exocrine gland and an endocrine gland
151
what does the exocrine pancreas produce?
about a litre each day of digestive juices which help to breakdown proteins, lipids, DNA/RNA etc
152
the endocrine pancreas consists of small, scattered islands of tissue called...
islets of langerhans, which produce a number of hormones including insulin
153
layers, inwards to outwards inc elastic membrane
Tunica intima, internal elastic membrane, tunica media, external elastic membrane, tunica adventitia
154
which leukocyte is the most common and multi lobbed?
neutrophil
155
which leukocyte has granules which stain red?
eosinophils
156
which leukocyte is the rarest and is bi-lobed?
basophil
157
what colour is a basophil
intensely stained blue-purple
158
which leukocyte is a precursor of macrophages?
monocytes
