Histology - IMMS Flashcards
(127 cards)
1
Q
What colours do haemotoxylin and eosin stain the cell nuclei an cytoplasm?
A
- Nuclei = blue - Cytoplasm = pink but colour varies depending on nature of cytoplasmic contents
2
Q
What do these stains show: - PAS - Van Gieson - Trichrome - Alcian Blue?
A
- sugars, e.g. goblet cells - elastic tissue - 3 types of cell - mucins
3
Q
Why do cells vary in size?
A
Depends on metabolic activity, e.g. lymphocytes smaller than nerve cells as aren’t as metabolically active (need less mitochondria)
4
Q
What are the 6 types of cell shapes?
A
- rounded - polygonal - fusiform - squamous (flattened) - cuboidal - columnar
5
Q
What common feature do metabolically active cells have?
A
Nucleoli (within nucleus, site of ribosomal RNA formation)
6
Q
What is chromatin? What are the two types?
A
Condensed DNA wound around histones. Can’t be transcribed unless decondensed. - Heterochromatin = permanently condensed - Euchromatin = becomes decondensed in the life cycle of the cell
7
Q
What is the mitochondria?
A
- powerhouse of cell - site of oxidative phosphorylation - have own nucleus
8
Q
What is RER?
A
Site of protein synthesis, lots of ribosomes
9
Q
What is SER?
A
- site of membrane lipid synthesis - processes synthesised proteins
10
Q
What is the Golgi apparatus?
A
- processes macromolecules synthesised in ER - prominent in plasma cells (called perinuclear ‘hoff’)
11
Q
What are the 3 parts of the Golgi apparatus?
A
- cis face = receives transport vesicles from SER, phosphorylase some proteins - medial Golgi = forms complex oligosaccharides by adding sugars to lipids and peptides - trans Golgi network (end) = sorts macromolecules into vesicles which bud from surface
12
Q
What are vesicles?
A
Small membrane-bound organelles used for transport, storage and exchanging cell membrane between compartments. An example is a lysosome
13
Q
How are lysosomes formed?
A
Hydrolyse vesicles fuse with endosomes to form endolysosomes
14
Q
What is the cytoskeleton? What does it contain?
A
- supports cell’s shape - microfilaments (actin) helps this (smallest, 5nm) - intermediate filaments (6 types) spread tensile forces through tissue = cytokeratin, desmin, glial fibrillary acidic, neurofilament, laminin, vimentin - microtubules act as a scaffold for chromosomes during mitosis + meiosis (made of tubulin) (largest, 25nm)
15
Q
What is lipofuscin and where is it found?
A
- membrane-bound orange-brown pigment, formed from peroxidation of lipids in older cells - heart and liver
16
Q
Where are lipids and glycogen found?
A
- lipids found in adipocytes (fat cells) - glycogen found in cytoplasm
17
Q
Are all the constituents of the body contained inside cells?
A
No, there is interstitial fluid, e.g. water + extra cellular material, e.g. tendons
18
Q
A sample of liver from a patient who has a disease that makes them store excess iron in the liver is examined by a pathologist. Which stain can be used to stain iron blue? A - Alcian blue B - Haemotoxylin C - Iron haemotoxylin D - Perl’s stain E - Periodic acid-Schiff stain
A
D - Perl’s stain
19
Q
Different cells have different lifespans. Which of the following cell types lives for the whole life of a person? A - Enterocytes (gut lining cells) B - Erythrocytes (red blood cells) C - Cardiac myocytes (heart muscle cells) D - Fibroblasts (connective tissue cells) E - Keratinocytes (skin cells)
A
C - Cardiac myocytes (heart muscle cells)
20
Q
Which stain(s) have been used on this section? A - Alcian Blue B - Giemsa C - Haemotoxylin and eosin D - Periodic acid Schiff E - Perls Prussian Blue
A
D
21
Q
What is the shape of these cells? A - Columnar B - Fusiform C - Polygonal D - Rounded E - Squamous
A
B
22
Q
What is the lifespan of these cells? A - 5 days B - 120 days C - 400 days D - 3600 days E - 21000 days
A
B
23
Q
What is chromatin? A - Mitochondrial DNA B - Nuclear DNA C - Nuclear DNA + proteins D - Nuclear RNA E - Nuclear RNA + proteins
A
C
24
Q
What is the function of the arrowed organelle? A - DNA transcription B - Energy production C - Lipid degradation D - Protein degradation E - Protein synthesis
A
A
25
Which metabolic process takes place here? A - Fatty acid metabolism B - Lipid synthesis C - Kreb’s cycle D - Nucleotide phosphorylation E - Respiratory chain
C
26
Which organelle causes this pale area? A - Golgi body B - Lysosomes C - Mitochondria D - Rough ER E - Smooth ER
A
27
What is the function of this organelle? A - Form complex oligosaccharides B - Form membrane lipid C - Protein phosphorylation D - Proteolysis E - Synthesise protein
E
28
Which of these filaments has the smallest diameter? A - Actin B - Desmin C - Nuclear laminin D - Tubulin E - Vimentin
A
29
Which of these intermediate filaments is predominantly found in muscle? A - Cytokeratin B - Desmin C - Neurofilament protein D - Nuclear laminin E - Vimentin
B
30
What is this pigment? A - Bilirubin B - Haemosiderin C - Lipofuscin D - Melanin E - Rhodopsin
C
31
What type of tissue is this? A - Bone B - Epithelium C - Germ cells D - Muscle E - Nerve
D
32
What is epithelia? What are the 3 purposes of the barriers it forms?
Epithelia comprise a cohesive sheet of cell, with one or more layers, resting on a basement membrane. Form barriers for protection, e.g. skin, absorption, e.g. gut and secretion, e.g. pancreas
33
What are the two types of epithelia regarding layers of cells?
- Simple epithelia = single layer of cells on basement membrane - Stratified (compound) epithelia = 2 or more layers of cells on basement membrane
34
Explain the shape of simple squamous epithelium.
- Single layer of flattened plate-like cells - Parallel oval nuclei (1 per cell) - Lines inside of blood vessels (endothelium), outside of lungs (mesothelium) + abdominal organs (peritoneum)
35
Explain the shape of simple cuboidal epithelium
- Single layer of cells with similar height + width - Central spherical nuclei - Line kidney tubules, small ducts
36
Explain the shape of simple columnar epithelium.
- Single layer of cells taller than they are wide - May or may not have cilia (wafts material on surface across epithelium) or microvilli (microvilli increase s.a. for absorption of water + nutrients) - Lines stomach, intestines + uterus
37
Where do we generally find stratified epithelia?
Found at sites subject to abrasive forces, e.g. mouth
38
Describe the shape of stratified squamous non-keratinising epithelium.
- Multiple layer of cells, plate-like squares - Produces no keratin, so found in areas not in need of waterproofing, e.g. oesophagus
39
Describe the shape of stratified squamous keratinising epithelium.
- Multiple layers of cells, plate-like squames - Keratin = waterproof, so found on skin
40
Describe the shape of pseudostratified epithelium
- Single layer of cells of variable height. Tricks you into thinking it’s multiple layers. - All in contact with basement membrane, but nuclei at varying heights
41
Describe the shape of urothelium (transitional epithelium).
- Breaks the rules - looks stratified, but is a mixture of stratified and pseudostratified - In stratified, bottom layer in contact with basement membrane - In urothelium, several layers are in contact with basement membrane - Top layer (umbrella layer) and then pseudostratified (appears 3-7 layers thick)
42
What is the basement membrane?
- Always present in epithelia, but can’t usually see it - Can infer its presence from difference in colour between epithelium and underlying connective tissue
43
What is used to stain basement membrane?
PAS
44
What is the basement membrane made up of?
Several extra-cellular proteins including Collagen IV + Fibronectin
45
How are epithelial cells joined together?
Epithelial junctions
46
Which epithelial junctions prevent diffusion between cells?
Occluding (tight) junctions
47
Which type of epithelial junction spreads forces across several cells?
Desmosomes
48
Which epithelial junction allows the spread of ions and small molecules between adjacent epithelial cells?
Gap
49
Where else might this type of epithelium be found? - A. Blood vessels - B. Renal tubules - C. Salivary ducts - D. Trachea - E. Urinary bladder
A
50
What type of epithelium is this? - A. Pseudostratified - B. Simple cuboidal - C. Simple columnar - D. Simple squamous - E. Stratified squamous
D
51
Which of these can be a feature of simple columnar epithelium? - A. Anucleate cells - B. Cells wider than they are tall - C. Microvilli on luminal surface - D. No basement membrane - E. Several cells thick
C
52
Where might one find a simple columnar ciliated epithelium? - A. Ectocervix - B. Fallopian tube - C. Gallbladder - D. Small intestine - E. Trachea
B
53
Where is this epithelium found? - A. Ectocervix - B. Eyelid - C. Oesophagus - D. Palm of hand - E. Vagina
D
54
Where might one find this epithelium? - A. Bladder - B. Nasopharynx - C. Oropharynx - D. Small intestine - E. Stomach
B
55
Which two proteins are principally involved in the generation of ciliary movement? - A. Actin and myosin - B. Actin and tubulin - C. Collagen and elastin - D. Tubulin and dyenin - E. Tubulin and myosin
D
56
Which statement is true regarding this epithelium? - A. All cells are in contact with the basement membrane - B. Found in gallbladder - C. It is pseudostratified - D. It is waterproof - E. It lines the vas deferens
D
57
Which type of collagen makes up this structure? - A. Type I - B. Type II - C. Type III - D. Type IV - E. Type V
D
58
Where are the stem cells in this epithelium?
D
59
Where might one find the hemidesmosomes (different to desmosomes - link cell to basement membrane)?
D
60
A gland that secretes by shedding individual cells is called what? - A. Merocrine - B. Apocrine - C. Exocrine - D. Endocrine - E. Holocrine
E
61
Where do connective tissue cells originate from?
Mainly derived from undifferentiated mesenchymal cells:
- fibroblast
- fat cells
- most cartilage and bone cells
Also from haemtapoetic stem cell line:
- monocytes
- macrophages
- lymphocytes
- mast cells
- blood cells and others
62
What are connective tissues made up of?
- Cellular component, e.g. fibroblasts, adipose cells
- Visible fibres (extracellular component), e.g. collagen, elastin
- Ground substance (hydrophilic jelly, invisible) that contains proteoglycans, glycosaminoglycans + invisible fibres like laminin. Invisible as does not stain with H&E, so appears as white stains
63
What are the 3 types of connective tissue?
- Fibrous. Either loose or dense depending on arrangement on collagen fibres within
- Hard. Either cartilage or bone
- Fatty. Either white or brown
64
What is the principal extra cellular fibre of connective tissues? How is it secreted?
Collagen. Fibroblasts secrete tropocollagen subunits.
65
Where are the first 5 types of collagen found?
- Type I = skin
- Type II = cartilage
- Type III = liver, bone marrow, spleen
- Type IV = basement membranes
- Type V = placenta
66
What colour do collagen fibres stain with H&E?
These extracellular fibres stain pink. They have a variable thickness + length. Often confused with muscle fibres (stain pink but intracellular, so nucleus lies within them). In image, collagen fibres labelled. Blue dots = nuclei of fibroblasts that have secreted collagen
67
How does loose connective tissue appear?
Widely spaced thin collagen fibres and fibroblasts. Unsteadiness ground substance
68
How does dense connective tissue appear?
Closely spaced thick collagen fibres and fibroblasts. Much less unstained ground substance. May be irregular (top) or regular (bottom)
69
What is reticulin? Which stain is used to view it?
Type III collagen that forms fibres. Provides supporting scaffold to epithelial cells in many organs, e.g. bone marrow, liver + kidney. Not visible on H&E - need silver stain
70
How is elastic tissue found? What is elastin? How does elastin stain with H&E?
Either found as fine fibres or as sheets of elastin. Elastin fibres may be branched or unbranched. Elastin is produced by fibroblasts. Stains pink with H&E.
71
What is fatty connective tissue mainly found in the form of? What are adipocytes?
- White adipose tissue
- Adipocytes are large cells containing a single fat globule. Appear as large white spaces.
72
What is brown adipose tissue? Where is it found?
Cells with many globules of fat. Found across shoulders and down back of newborn. Important in neo-natal thermoregulation.
73
What is cartilage? What does it comprise?
Hard connective tissue. Comprises 2 cell types, chondroblasts (immature) + chondrocytes (mature). These are set in an extracellular matrix rich in glycosaminoglycans + proteoglycans. Cartilage is AVASCULAR
74
What are the 3 types of cartilage?
- Hyaline cartilage
- Elastic cartilage
- Fibrocartilage
75
Where is hyaline cartilage found? How does it appear?
- Found in synovial joints
- Chondrocytes surrounded by glassy matrix
- No visible fibres
- Perichondium on outside has fibroblasts and collagen
76
Where is elastic cartilage found? How does it appear?
- Found in pinna of ear and epiglottis
- Visible elastic fibres
- Bound by a perichondrium of fibroblasts and collagen
77
Where is fibrocartilage found? How does it appear?
- Found in annulus fibrosus + pubic symphsis
- Visible collagen fibres in matrix
- Perichondrium
78
What is synovium?
Another connective tissue that binds synovial joints. Lines inside of joint capsules + 1-4 layers of synovial cells. Richly vascular
79
What are the 2 types of synovial cells?
- Type A = phagocytes
- Type B = rich in RER
80
Are muscles a type of connective tissue? What are the 3 categories of muscle?
Yes. Smooth, e.g. arterial wall, skeletal + cardiac
81
How does smooth muscle appear?
Fusiform cells, central nucleus, no striations
82
How does skeletal muscle appear?
Striated, multiple nuclei per muscle cell near edge of individual muscle fibres, no branching
83
How does cardiac muscle appear?
Striated (but harder to see than skeletal), central nuclei + branching
84
How can you decide what type of muscle a specimen is?
- Is it striated? No = smooth, yes= skeletal or cardiac muscle
- Where are the nuclei? Centre = cardiac, edge = skeletal
85
What is the general structure of arteries?
- Squamous endothelial cells surround lumen. Rest on basement membrane (as do all)
- Surrounded by loose connective tissue (intima)
- Bound by internal elastic laminate (elastic tissue)
- Media = thick layer of connective tissue, comprising smooth muscle, some fibroblasts + variable amounts of collagen and elastin
- Surrounded by external elastic lamina
- Adventitia = layer of loose connective tissue
86
Where are elastic arteries found? What do they look like?
- Large arteries near heart (aorta + pulmonary arteries)
- Have layer of endothelial cells (resting on basement membrane), intima lies on top of this, internal elastic lamina, media (contains sheets of elastin), external elastic lamina + adventitia
87
What are muscular arteries? What do they look like?
Most abundant. Media comprises layers of smooth muscle although sheets of elastin are still found. Example = radial artery (wrist)
88
What is an arteriole? How do they appear?
- Arterioles are resistance vessels, different to arteries as either less than 100 um in diameter or have 3 or fewer muscle layers. Elastic laminae poorly defined
89
How is the structure of capillaries different to the structure of arteries?
No adventitia, no external elastic lamina, no media, no internal elastic lamina, no intima. Only endothelial cells on a basement membrane. Have pericytes on outside to constrict and relax.
90
What are fenestrated capillaries? Where do these appear?
Endothelial layer = incomplete, so windows form which facilitate movement of materials. Appear in kidneys + liver
91
How do capillaries appear under the microscope?
Capillaries drain into venous system
92
How is the structure of veins and venules different to arteries?
No external elastic lamina, have a bigger lumen and a thinner media
93
How do venules appear under a microscope?
- Associated with arterioles, thin walled. Pericytes from arterioles wrap around outside of endothelial cells + form complete layer as venules get larger. Pericytes replaced by smooth muscle as venules become veins
94
How do veins appear under a microscope?
Large veins are thick walled (larger media) compared to venules, but thin walled compared to arteries. Smooth muscle in wall may be circular or longitudinal
95
What are lymphatics? How do they appear under a microscope?
- Thin walled like capillaries and veins + have valves
- Don't contain blood, pink on slide is the lymph. May contain lymphocytes though
96
How do peripheral nerves appear?
- Composed of axons
- Supported by Schwann cells that produce myelin
- Most axons are myelinated (insulating sheath)
97
What are the 3 types of connective tissue within peripheral nerves?
- Endoneurium = present between individual axons
- Perineurium = surrounds groups of axons to form fascicles
- Epineurium = binds fascicles together to form nerve fibres
98
What is a neuro-vascular bundle?
Nerves alongside blood vessels. Commonly found together in histological samples
99
What is myelin? How is it stained?
- Insulates axons
- A spiral of apposed Schwann cell membranes
- Multiple Schwann cells per myelinated axon
- Schwann cell wraps itself around axon multiple times to produce myelin layer
- Gaps between Schwann cells = Nodes of Ranvier
- Doesn't stain with H&E, but can be appreciated when silver stains are applied
100
What is the difference between myelinated and unmyelinated axons?
- Multiple Schwann cells present along length of all axons
- Myelinated = single axon related to single Schwann cell at any given point
- Unmyelinated = multiple axons associated with single Schwann cell at any point
101
Images of myelinated axon.
102
How do neurons convey information? Can these be viewed through a microscope?
- Release of neurochemicals at synapses which form junctions between adjacent neurons or between neurons and effector organs. Can be viewed by electron microscopy.
103
Where are cell bodies found in different neurons?
- Motor neurons = grey matter of spinal cord
- Sensory neurons = dorsal root ganglia
- Sympathetic neurons = grey matter of spinal cord + adjacent sympathetic ganglia
- Parasympathetic neurons = brain + local ganglia
104
Examples of neuron cell bodies under a microscope.
105
Which of the following is derived from a haematopoetic stem cell?
- A. Adipocyte
- B. Fibroblast
- C. Chondroblast
- D. Monocyte
- E. Osteoblast
D
106
Elastin is found in the walls of elastic arteries. Which cells produce elastin?
- A. Elastoblasts
- B. Elastocytes
- C. Elastoplasts
- D. Fibroblasts
- E. Hepatocytes
D
107
Which of the following is a 'visible' extracellular fibre?
- A. Fibronectin
- B. Glycosaminoglycan
- C. Laminin
- D. Proteoglycan
- E. Reticulin
E
108
Type V collagen is prevalent in which tissue type?
- A. Bone
- B. Kidney
- C. Liver
- D. Placenta
- E. Skin
D
109
Which of these structures contains elastic cartilage?
- A. Epiglottis
- B. Intervertebral disc
- C. Knee joint
- D. Nasal septum
- E. Symphysis pubis
A
110
What type of tissue is this?
- A. Brown adipose
- B. Hyaline cartilage
- C. Lung
- D. Loose fibrous
- E. White adipose
E
111
Where is this tissue most likely to be found in adults?
- A. Around aorta
- B. Around kidneys
- C. Between shoulder blades
- D. In omentum
- E. In subcutis
C
112
What is the primary function of this connective tissue?
- A. Glycogen synthesis
- B. Energy store
- C. Heat generation
- D. Insulation
- E. Shock absorber
C
113
Which of the following contains dense regular fibrous connective tissue?
- A. Arterial adventitia
- B. Dermis
- C. Penile erectile tissue
- D. Penile fascia
- E. Tendon
E
114
What type of connective tissue is this?
- A. Bone
- B. Brown fat
- C. Elastic cartilage
- D. Hyaline cartilage
- E. Loose fibrous
C
115
In which structure is this tissue found?
- A. Achilles' tendon
- B. Intercostal muscle
- C. Left ventricle
- D. Tongue
- E. Uterine wall
E
116
Which of these is an elastic artery?
- A. Aorta
- B. Brachial artery
- C. Coeliac artery
- D. Splenic artery
- E. Radial artery
A
117
What type of vessel is this?
- A. Elastic artery
- B. Lymphatic
- C. Muscular artery
- D. Vein
- E. Venule
C
118
Which structure is present in arteries but not veins?
- A. Endothelium
- B. Intima
- C. Internal elastic lamina
- D. Media
- E. External elastic lamina
E
119
Which statement regarding capillaries is true?
- A. Their diameter is regulated by pericytes
- B. They are all fenestrated
- C. They have an intima and media
- D. They have a thick adventitia
- E. They lack a basement membrane
A
120
Which statement regarding these vessels is true?
- A. They are present in cartilage
- B. They contain blood
- C. They contain valves
- D. They have a prominent internal elastic lamina
- E. They have a thick media
C
121
What type of vessel is this?
- A. Arteriole
- B. Capillary
- C. Lymphatic
- D. Muscular artery
- E. Venule
A
122
What is X?
- A. Endoneurium
- B. Epineurium
- C. Myelin
- D. Perineurium
- E. Schwann cell
A
123
Which cells produce myelin?
- A. Fibroblasts
- B. Neurons
- C. Pericytes
- D. Schwann cells
- E. Smooth muscle cells
D
124
Which statement about the arrowed structure is true?
- A. It contains perineurium
- B. It is a break in an axon
- C. It is a synapse
- D. It is a Schmidt-Lanterman incisure
- E. It is devoid of myelin
E
125
How many axons are myelinated by a single Schwann cells?
- A. 1
- B. 2-3
- C. 4-5
- D. 6-7
- E. 8+
A
126
What is structure X?
- A. Mitochondrion
- B. Myelinated axon
- C. Neurosecretory granule
- D. Schwann cell nucleus
- E. Unmyelinated axon
E
127
If this structure shown relates to sensory peripheral nerves, where is it?
- A. Brain
- B. Dorsal root ganglia
- C. Spinal cord grey matter
- D. Sympathetic ganglia
- E. Wall of small intestine
B
