Unit 4- Mammalian Tissue Flashcards
1
Q
What is a tissue?
A
Group of similar cells that work together to perform a specific function
2
Q
What is the function epithelial tissue?
A
- Covers and protects underlying tissue from damage/ injury/ germs/ drying out
- forms a continuous sheet of cells covering external and internal surfaces of body
- attached to underlying tissue by basement membrane
- does not contain blood vessels
3
Q
Location of epithelial tissue?
A
- Epithelium- outside
- covers the body - Endothelium - inside
- lines body cavities, passages and ducts
4
Q
How is epithelial tissue classified?
A
- number of layers
2. shape of cell
5
Q
Where is squamous tissue found?
A
Inner lining of:
- mouth
- Vagina
- Oesophagus
- Blood vessels
- Alveoli
6
Q
What is the structure of squamous epithelial tissue?
A
- Single layer of thin, flat, closely packed cells with a large surface area
- Spherical central nuclei
7
Q
What are the functions of squamous epithelial tissue?
A
- Quick and efficient diffusion of substances
2. Protect and support underlying tissue
8
Q
Where is simple columnar epithelium found?
A
- Stomach
- Small intestine
- Urethra
- Vas deferens
- Prostate gland
- Uterus
9
Q
What is the structure of simple columnar epithelium?
A
- Single layer of column shaped closely packed cells
2. Oval nucleus near base
10
Q
What are the functions of simple columnar epithelium?
A
- Absorb nutrients
- Produce secretions
Protect and support underlying cells
11
Q
How is a goblet cell shaped to suit its functions?
A
- Cup shaped
- trap dust and germs
- secrete mucus to keep structure moist
12
Q
Where is violated columnar epithelium found?
A
- Nasal cavity
- Trachea
- Bronchi
- Fallopian tubes
- Vas deferens
13
Q
What is the structure of ciliated columnar epithelium?
A
- Columnar epithelium with cilia on free surface
2. Can have goblet cells
14
Q
What are the functions of ciliated columnar epithelium?
A
- Filter air
2. Movement of substances
15
Q
Where is columnar epithelium with microvilli found?
A
- Small intestine
16
Q
What are microvilli?
A
Microscopic hair-like folds
1. Increase surface area for substance/ nutrient absorption
17
Q
What is the structure of columnar epithelium with microvilli?
A
- Elongated cells
- Microvilli on free surface
- Free and highly folded
18
Q
Where are cuboidal/ glandular cells found?
A
- Line ducts and glands
19
Q
Structure of cuboidal/ glandular epithelium?
A
- Lots of Golgi apparatus in glands
2. No intercellular spaces- has round, central nuclei
20
Q
Function of cuboidal/ glandular epithelium?
A
- Absorb nutrients (ducts)
2. Produce secretions (glands)
21
Q
What is the structure of connective tissue?
A
- Relatively few cells of various cell types
- Various fibers
- A matrix
- Cells are spread apart and spaces between in filled with matrix
22
Q
What are the functions of connective tissues?
A
- Binds tissues and organs together to support body
2. Transports substances within the body
23
Q
What is the function of soft connective tissue?
A
- Binds epithelium to other tissues & holds organs in place
24
Q
Location of areolar tissue
A
- Continuous layer under skin
2. Fills in between muscles/ organs and blood vessels
25
What is the structure of areolar tissue?
1. Most common
2. Loose & irregular arranged tissue
3. Jelly-like matrix
- WHITE collagen fibers (branched/ inelastic & parallel)
- YELLOW elastic fibers ( small/ elastic & branched)
26
What is the function of areolar tissue?
1. Attaches underlying muscle to bone
27
Where is adipose tissue found?
1. FAT- under skin
28
What is the structure of adipose tissue?
1. Few fibers
2. Fat storing cell
3. Very thick= blubber
29
What are the functions of adipose tissue?
1. Energy
| 2. Insulation
30
Mast cell
1. Secretes matrix & anticoagulant
31
Macrophage
1. Defensive role ( engulfs foreign particles)
32
Fibroblast
1. Secretes different fibers
33
Yellow elastic fiber
1. Flexible - forms branch network
34
White collagen fibers
1. Non- flexible - keeps everything tight & together
| "ANCHOR"
35
Fat cells
1. Store fat - lots of fat cells in areolar tissue= adipose
36
Ground substance
1. All cells embedded in
- jelly-like
- white substance
37
What is fibrous connective tissue?
1. Strong network of collagen fibers
38
Location and structure of a ligament
1. Between bones
| 2. Yellow Elastic Fibres
39
Function of ligament
1. Keeps joints stable
2. Able to stretch
- allow bones to move in different directions from joint
40
Location and structure of tendons
1. Connect muscle to bone 2. White Collagen fibres
41
Function of tendons
1. Grows in bone & strengthens it
| 2. Inelastic- transmit contraction & relaxation of muscle to bone for movement
42
What is dense connective tissue?
1. Dense tissue with little matrix
2. Many inelastic fibres, small number of elastin fibres with a small number of fibroblasts between the fibres
- conjunction with muscle, cartilage and bone in outer TRACHIAL, BRONCHIAL WALLS & BLOOD VESSELS
43
Function of dense connective tissue?
1. Forms fascia, perichondrium & periosteum
2. Provides necessary elasticity in trachea, bronchi, vocal chords & blood vessel walls -> only yellow elastic fibres in these structures
- joins bone to bone as ligament
- joins muscle to bone as tendons
44
Structure of cartilage tissue
1. Contains chondrocytes
- secrete rubbery matrix made from chondrin ( protein)
- occur in small fluid filled spaces called lacunae
2. Matrix also contain white collagen fibres and yellow elastic fibres
- no nerves/ blood vessels in matrix
45
What is the perichondrium?
1. Fibrous capsule that surrounds cartilage
| 2. Well supplied by blood vessels but has no nerves
46
Structure of hyaline cartilage
1. Extremely low number of collagen fibres
2. No elastic fibres
3. Firm, jelly- like matrix
4. Clear, glass- like appearance
47
Location of hyaline cartilage
1. End of long bones/ bones in movable joints
2. Attaches ribs to sternum
3. Forms 'c' rings in trachea
4. Larynx and bronchi
48
Function of hyaline cartilage
1. Reduces friction in joints
2. Attaches bone to bone so movement is possible
3. Keeps tubes open
4. Forms permanent structures
5. Longitudinal growth in long bones
49
Structure of white fibrous cartilage
1. Many collagen fibres arranged in bundles
| 2. Does not have perichondrion
50
Location of white fibrous cartilage
1. Intervertebral disc
2. Pubic symphysis
3. Sockets of ball and socket joints
51
Functions of white fibrous cartilage
1. Shock absorber between vertebra
2. Flexibility
4. Protects tendons
52
Structure of yellow elastic cartilage
1. Contains collagen fibres
2. Network of branched elastic fibres
3. Not as glossy- fibres embedded in matrix
53
Location of yellow elastic cartilage
1. Tip of nose
2. Pin a of ear
3. Epiglottis
4. Eustachian tubes
54
Function of yellow elastic cartilage
1. Maintains shape & flexibility
| 2. Gives support to structure
55
Haversian canals
1. Central canals
2. Run through bones longitudinally
3. Contain blood vessels, nerves and lymph vessels
56
Matrix of bone tissues
1. Occur in concentric circles- LAMELLAE- around Haversian canals
2. Contain collagen fibres -> bone not brittle
- contains inorganic substances: Ca, P, Mg = hard matrix
57
Lacunae between lamellae
1. Each lacuna contains an osteocyte
58
What is a canalculi?
1. A fine canal that links lacuna to Haversian canal
- allows movement of useful substances (nutrients, O2) and cellular waste to & from blood of Haversian canal to & from all parts of bone tissue
59
What is blood?
1. Liquid connective tissue formed by blood floating in plasma
60
What is the composition of blood?
1. 55% plasma
| 2. 45% cells
61
What is plasma composed of?
1. Pale straw colour
2. 90% water
3. Contains inorganic ions (Na, K, Cl)
4. Organic compounds ( glucose, amino acids)
5. Cellular wage- urea & uric acid
6. Dissolved gases - CO2 & O2
7. Plasma proteins - fibrinogen & albumen
8. Hormones and enzymes
62
What cells are found in blood?
1. Erythrocytes
2. Thrombocytes
3. Leukocytes
63
What is the structure of erythrocytes?
1. Red blood corpuscles- carry O2 & CO2
- small, round
- biconcave discs with no nuclei
- hemoglobin- red pigment
- combine with O2 -> oxyhemoglobin
64
What is significant about the structure of erythrocytes?
1. A lot of cells = large surface area for O2 absorption
2. Biconcave shape makes surface area for absorption larger
3. Flexible - able to be pushed through small blood vessels
65
What is the structure of leukocytes?
1. White blood cells
| - large & irregularly shaped with nuclei
66
What is significant about the structure of leukocytes?
1. Move actively through amoeboid movement & engulf foreign particles
- can move out of blood vessels & into intercellular spaces in tissues
2. Can produce antibodies -> destroy bacterial toxins
67
What is the structure of muscle tissue?
1. Long & thin
2. Parallel to each other
3. Many mitochondria
1. Specialists of contraction & relaxation
- specialized to cause movement
- works antagonistically to carry out mechanical work
68
Skeletal muscles
( striated/ striped/ voluntary)
- attached to bones & tendons
1. Muscle fibres lie parallel to one another
2. Voluntary co-ordinated movement of the skeleton
69
Smooth muscles
( unstriated/ unstriped/ involuntary)
- walls of internal organs
1. Spindle shaped
2. Nuclei twist when muscle contracts
3. Form continuous sheet
1. Involuntary movement
2. Contracts slowly
3. PERISTALSIS-
Movement of substances along internal passage ways
70
Cardiac muscle
- walls of heart ( myocardium
1. Branched cells similar to skeletal
2. Ends joined by intercalated discs
3. Striated and can have more that one nucleus
1. Involuntary movement
2. Not subject to fatigue
3. SYNCYTIUM-
Muscle bridge + intercalated bridge
71
What is nervous tissue?
1. Made up of neurons
- transmit nerve impulses from sensory organs to the central nervous system
- from CNS to effector organs (muscles & glands) of body
72
What types of nerve tissue is there?
1. Sensory neuron
2. Motor neuron
3. Inter/ connective neuron
73
Structure of nerve tissue
1. Consists of a cell body, single prominent neuron & differentiated outgrowths
74
Nissl bodies
1. Occur in cytoplasm of cell body
| 2. Mainly RNA & ribosomes -> plays a part in protein synthesis
75
Two types of nerve tissue outgrowths
1. Dendrites - transmit impulses towards body
2. Axon- transmit nerve impulses away from cell body
• only 1 axon but multiple dendrites according to function
76
Neurilemma
1. Series of consecutive cells that enclose the axon
| 2. Form a strong outer covering
77
Schwann cell
1. Neuron that occurs in peripheral nervous system
| 2. Produces myelin sheath
78
Myelin sheath
1. Protective layer inside neurilemma
| 2. Insulator to prevent short circuit in nervous system
79
Nodes of Ranvier
1. Gaps in the myelin sheath
2. Myelin sheath & neurilemma are discontinuous
- nerve impulses move in one direction only
STIMULUS -> DENDRITES -> AXON
80
Synapse
The site where a nerve impulse is transmitted from one neuron to the next
- there is no physical connection between neurons in this gap
81
Neurotransmitters
1. Special chemical molecules used to allow nerve impulses across synapse
