Muscle Tissue Flashcards
What are the three types of muscle tissue?
-striated muscle
-smooth muscle
-cardiac muscle
Where can skeletal and striated muscle be found ?
Found attached to bones
Where can cardiac muscle be found?
Found only in the heart
Striated muscle
The sarcolemma of individual muscle fibres is in direct contact with an external lamina the ………….
Endomysium
What does the endomysium do?
This joins groups of muscle fibre to each other and supports the capillaries and nerve axons which run between the fibres.
Larger groups of muscle fibres are bound together by …….. (connective tissue) into…….
1.perimysium
2. Fascicles
An anatomical muscle is composed of many fascicles surrounded by a stronger connective tissue fascia - the …….
Epimysium
What is hypertrophy?
Where muscle fibres increase in size
The contractile unit of skeletal muscle is the ………… .This passes from the centre of one actin group to the next, in the resting state it is about ……..um long.
1.sacromere
2. 2.2
A length of sarcomeres constitutes a myofibril, this is about …….um in diameter.
1-2
Several myofibrils are grouped together by a cell membrane, termed the …………, to form a muscle fibre, typically ………..um in diameter and up to …….cm long.
1-sarcolemma
2. 50-60
3. 10
Explain the banding pattern to be seen in myofibrils
● I-bands - light bands containing only thin actin filaments
● A-bands - dark bands containing thick myosin filaments (and some actin filaments)
-H zone contains only myosin
-Darkest region contains overlapping actin and myosin
Give an overview of muscle contraction
● Myosin heads slide actin along myosin causing the sarcomere to contract
● Simultaneous contraction of many sarcomeres causes myofibrils and muscle fibres to contract
● When sarcomeres contract (shorten)…
- H zones get shorter
-I band get shorter
-A band stays the same
-Z lines get closer
Draw a contracted sarcomere
Which muscle type is this, its description, function and location.
-smooth muscle
-description: spindle shaped (elongated) cells with central nuclei; no striations; cells arranged closely to form sheets
-function: propels/ pushes substances or objects ( foodstuffs, urine, a baby) along internal passageways; involuntary control
-location: mostly in the walls of hollow organs
Which type of muscle tissue is this under the microscope?
Smooth muscle
Smooth muscle
-Each smooth muscle cell is spindle-shaped. Cells may be ……um long in small blood vessel walls and up to ………um long in the uterus.
-There is a single nucleus centrally placed. Cells are surrounded by an external ………….. which is attached to the cell membrane.
-There is no regular arrangement of actin and myosin in the cell. The …………… proteins crisscross the cell and insert into anchoring points on the cell membrane.
-Contraction of the proteins is transmitted through the cell membrane to the surrounding external lamina. Adjoined cells contract as one unit.
1.20
2. 400
3. Lamina
4. Contractile
Which muscle tissue type is this, its description, function and location?
-cardiac muscle
-description: branching, striated, generally uninucleate cells that interrogate at specialised junctions ( intercalated discs)
-function: as it contracts, it propels blood into the circulation; involuntary control
-location: the walls of the heart
Which type of muscle tissue is this under the microscope?
Cardiac muscle
CARDIAC MUSCLE
-Cardiac muscle cells are also mononucleated. Each cells is about …..um in diameter and 100um long.
-The cells are ……………. and form long chains with neighbouring cells.
-Intercellular junctions can be seen as dark lines, these are intercalated discs which contain …………..for strength and gap junctions for cell-cell communication.
-The ……………proteins actin and myosin are arranged in a specific way which creates bands within the cell - striations. Mitochondria are prominent throughout the cells.
- 15
2.branched
3.desmosomes
4.contractile
