Histology Flashcards
(96 cards)
1
Q
Explain the 3 layers that make up blood vessels
A
Tunica intima (squamous epithelial cells) Tunica media (smooth muscle) Tunica adventitia (supportive connective tissue)
2
Q
What seperates the tunica media from the tunica adventitia
A
external elastic membrane
3
Q
What seperates the tunica media from the tunica intima
A
internal elastic membrane
4
Q
Explain what elastic arteries are
A
- large arteries e.g. aorta
- contain sheets of elastic fibres
- provide elastic recoil
5
Q
Explain the histology of arterioles
A
- contain 1 or 2 layers of smooth muscle
- almost no tunica adventitia
6
Q
Explain the histology of capillaries
A
- endothelial cells and basal lamina
- may contain pericytes
7
Q
What are pericytes
A
connective tissue with contractile properties
8
Q
What are the 3 types of capillaries
A
- continous (muscle, connective tissue)
- fenestrated (small pores - gut, endocrine glands)
- discountious (large gaps - liver, spleen)
9
Q
What are the 3 layers of the heart
A
- endocardium
- myocardium
- epicardium
10
Q
Where are intercalated disks found and what is their purpose
A
- found in the contractile cardiac muscle in the myocardium
- allows the spread of electrical activity
11
Q
Two types of pericardium
A
- fibrous (fibrocollagenous connective tissue)
- serous (simple squamous epithemlium)
Serous lies in the inner surface of the fibrous pericardium
12
Q
What lie inbetween the 2 pericardiums?
A
pericardial cavity
small amount of fluid for lubrication
13
Q
Explain the histology of the heart valves
A
- outer endothelial layer with basal lamina
- layer of collagen and elastin fibres
- lamina fibrosa lies on the fibrous skeleton
- chordae tendineae (fibre like)
14
Q
What would pacemaker cells look like down the microscope
A
- pale in colour
- smaller than contractile myocytes
15
Q
What would purkinnje fibres look like down the microscope?
A
- paler in colour
- larger than cardiac muscle cells
- found in subendocardial layer
16
Q
What are the 5 main components found in all Eukaryotic Cells?
A
- an outer membrane
- inner cytosol
- cytoskeleton
- membrane bound organelles
- inclusions
17
Q
What are inclusions
A
- other structures within the cytoplasm which may or may not be bound by a membrane
18
Q
What is the cytosol?
A
solution of proteins, electrolytes and carbohydrates
it has a fluid/gel-like properties
19
Q
What is the plasmalemma?
A
- separates the cytoplasm from the outside environment
20
Q
What is the plasmalemma composed of?
A
- amphiphatic phospholipids
- hydrophilic head
- hydrophobic (fatty acid) chains
- may contain integral proteins
21
Q
What are 2 main differences between inclusions and organelles?
A
- inclusions are non-living, may or may not be membrane bound
- organelles are living and are membrane bound
22
Q
What is the job of the rough endoplasmic reticulum?
A
- protein synthesis
- studded with ribosomes
23
Q
What is the job of the smooth endoplasmic reticulum?
A
- cholesterol and lipid synthesis
24
Q
What are the 3 main classes of filaments in the cytoskeleton? and what are their sizes?
A
- microfilaments (7um)
- intermediate filaments (>10um)
- microtubules (25um)
25
Explain microfilaments
- 7um
- composed of protein actin
- assemble and disassemble --> very dynamic
26
Explain intermediate filaments
- >10um
| - bind intracellular elements together and to the plasmalemma
27
Explain microtubules
- hollow tubule composed of alpha and beta tubulin
- originate from centrosome
- include stabilising proteins (MAPS)
- they are polar
28
What are kinesin and dynein?
| what way do they move?
They are both ATPases that attach to microtubules
- Kinein moves to cell periphery
- Dynein moves to cell centre (dynein comes home for dinner)
29
Name given to the gap between the outer and inner nuclear membrane?
- perinuclear cistern
30
Euchromatin
- DNA that is more dipsersed
| - actively undergoing transcription
31
Heterochromatin
- DNA that is highly condenses
| - not undergoing transcription
32
What is the endoplasmic reticulum (ER) and what are the 2 categories?
- forms a network of interconnecting membrane bound compartments in the cell
- SER
- RER
33
What is the Golgi complex composed of?
- flattened, membrane bound cisternae
34
What is the role of the Golgi complex?
- modification and packaging of macromolecules that arrive from SER and RER
35
What is the Cristae?
- Innerfolds of the mitochondrial membrane
36
What are intracellular junctions?
- specialised membrane structures which link individual cells together into a functional unit
37
What are the 3 types of intracellular junctions?
- occluding
- anchoring
- communicating
38
What do occluding junctions do?
- join cells together to create a diffusion barrier
39
What do anchoring junctions do?
- provide mechanical strength
40
What do communicating junctions do?
- allow movement of molecules between cells
41
What is a junctional complex?
- close association of several types of junctions found in certain epithelial tissues
42
Another name for occluding junctions?
- Tight junctions
43
Another name for anchoring junctions?
- desmosomes
44
Another name for communicating junctions?
- gap junctions
45
Explain how a tissue sample is made?
- tissue fixed
- thinly sliced
- impregnated with wax
- dehydrated, hot solvent
- cut thinly on microtome
- washed
46
What is haematoxylin?
- basic dye
- affinity for acidic
- stains purplish/blue
47
What is eosin?
- acidic dye
- affinity for basic
- stains pink
48
What are the 4 different types of tissue?
- epithelium
- connective tissue
- muscle tissue
- nervous tissue
49
What is the role of epithelium?
- cover body surfaces and line hollow organs
- mechanical barriers
- chemical barriers
- glands
50
What is the role of connective tissue
- in the growth, development and homeostasis of tissues
51
What is the role of muscle tissue?
- specialized cells to generated force by contraction
52
What is the role of nervous tissue?
- rapid communication between cells
| - made up of neurons and their supporting cells (glia)
53
True or false
| "epithelium is non-vascular"
true
54
What are the 3 different shapes of epithelium?
- squamous
- cubodial
- columnar
55
What are the 3 different layers of epithelium called?
- simple
- stratifies
- psuedostratified
56
What is glandular epithelium?
- produces secretory products, such as oil, sweat, tears and milk
57
What are exocrine glands?
- secret towards apical end
| - ducted glands
58
What are endocrine glands?
- secret towards basal end
- ductless glands
- to circulatory system (look for cappilaries)
59
3 different types of connective tissue?
- hard
- soft
- blood and lymph
60
what does connective tissue consist of?
- extracellular matrix
| - cells
61
3 different types of hard connective tissue?
- hyaline
- elastic
- fibrocartilage
62
3 different types of muscle tissue?
- smooth
- skeletal
- cardiac
63
Explain smooth muscle
- involuntary
- central nucleus
- no stritations
- visceral
64
Explain cardiac muscle
- involuntary
- stritated
- single nucleus
- intercalated discs
65
Explain skeletal muscle
- voluntary
- cylindrical
- multinucleated
- stritated
66
Explain what multipolar nerves mean?
- many dentrites
| - 1 axon
67
Explain what psuedounipolar nerves mean?
- same direction
68
Explain what bipolar nerves mean?
- one dentrite
| - one axon
69
What are the 3 different types of glia?
- oligodenrocytes
- astrocytes
- microglia
70
Role of microglia?
- provide immune surveillance
71
Role of oligodendrocytes
- produce myelin in the brain and spinal cord
72
Role of astrocytes?
- support ion transport
| - induce blood brain barrier
73
What are the 3 main salivary glands?
- parotid
- submandibular
- sublingual
74
What is the most external tissue on the digestive tract?
- muscularis externa
75
what is the name of the digestive tract nervous system?
-enteric nervous system
76
explain the histology of bronchi, bronchioles and alveoli
- bronchi larger in size, hyaline cartilage
- bronchioles, smaller, no cartilage, smooth muscle
- alveoli simple squamous epithelium
77
what is the liver made up of?
- lobules
78
What shape is a lobule in the liver?
- hexagonal
79
What veins/arteries are on the corner of a liver lobule?
- hepatic vein
| - heaptic artery
80
Where is the central vein located in a liver lobule
- centre of hexagon
81
What is unique about the pancrease glands?
- endocrine and exocrine
82
what does the pancrease endocrine glands secrete?
- insulin
83
What does the pancrease exocrine glands secrete?
- digestive juices
84
What are the three layers of blood vessels
- tunica intima
- tunica media
- tunica adventitia
85
What is the tunica intima?
- innermost of blood vessel
| - composed of squamous epithelium
86
What is the tunica media?
- composed of smooth muscle
87
What is the tunica adventitia?
- supporting connective tissue
88
What are the names of the membranes that seperates tunica intima and tunica media?
- internal elastic membrane
89
What are elastic arteries?
- larger arteries
- provides elastic recoil
- sheets of elastic tissue replaces smooth muscle
90
Define vasa vasorum?
- large arteries have their own vascular supply
91
What are capillaries composed of?
- endothelial cells
| - basal lamina
92
what are the 3 types of capillaries?
- continous
- fenestrated
- discontinuous
93
What are the histological differences in large veins?
- thick tunica adventitia
| - contains smooth muscle
94
Describe erythrocytes
- no nucleus
- red blood cell
- biconcave
- survive 4 months
- 7um in size
95
Describe neutrophils
- granules
| - multi-lobed nucleus
96
What would eosinophils look like down a microscope
- bilobed nuclease
