Veterinary General Physiology - Lecture
Finals Exam
Muscle - ANSWER>>Highly organized microfilament-based structure
Muscle - ANSWER>>A specialized cell that contracts to pull an external structure
or squeeze a fluid
Muscle - ANSWER>>Can produce a force that can be transmitted over a
considerable distance and can generate large and often rapid movements
Muscle - ANSWER>>Largest group of tissue in the body (most vertebrates)
Muscle - ANSWER>>Can shorten and develop tension from highly developed
microfilament system - enables them to produce force and do work
Muscle - ANSWER>>Converts the chemical energy of ATP into mechanical energy
that can act on the environment in response to electrical signal
Types of Muscles - ANSWER>>Skeletal
Cardiac
Smooth
Functions of Muscles - ANSWER>>1. Emptying of contents of certain organs -
urination and emptying of bile
2. Manipulation of external objects
3. Propulsion of contents
4. Purposeful locomotory movement
5. Production of heat as a metabolic by-product - thermoregulation
6. Production of sound
,Structure of Skeletal Muscle - ANSWER>>Whole muscle - muscle fiber - myofibril -
thick and thin filaments - myosin and actin
William Bowman - ANSWER>>Studied the structure of skeletal muscle in the
1830's using more than 40 animal species
A Band - ANSWER>>consist of a stacked set of thick filaments with a portion of
thin filament that overlap on both ends of the thick filaments
I Band - ANSWER>>consist of remaining portion of the thin filaments that do not
project into the A band
Z Line - ANSWER>>a flat cytoskeletal disc a line visible in the middle of each I band
Sarcomere - ANSWER>>an area between two Z lines (functional unit of a muscle)
H Zone - ANSWER>>the lighter are in the middle of A band where thin filaments
do not reach
M Line - ANSWER>>made up of supporting proteins, extends vertically down the
middle of the A band within the center of H zone
Similarities between Skeletal, Smooth, and Cardiac muscles - ANSWER>>1. both
have specialized contractile apparatus (actin and myosin)
2. Needs calcium for contraction
3. directly uses ATP as energy source of cross-bridge cycling
Differences between Skeletal, Smooth, and Cardiac muscles - ANSWER>>1.
Structure and organization of fibers
2. Mechanism of excitation and contraction
3. Distinction in contractile responses
Skeletal Muscle Cells - ANSWER>>- Striated and voluntary
, - Large, cylindrical, multinucleated
- lies in all skeletal muscles
- extends in the full length of skeletal muscles
- with numerous myofibrils, T tubules, and SR
Smooth Muscle Cells - ANSWER>>- Small and unstriated
- Elongated, spindle-shaped, with single nucleus
- lie in the walls of hollow organs and tubes
- Contraction exerts pressure on and regulates the forward movement of contents
of hollow organs and tubes
- Do not extend to the full length of a muscle
arrange in sheets
3 Types of filaments of Smooth Muscle Cells - ANSWER>>1. Thick myosin
filaments (longer than skeletal muscle)
2. Thin actin filaments with tropomyosin only
3. Filaments of intermediate size (not contractile)
Smooth Muscle Cells - ANSWER>>- Do not form myofibril
- Not arranged in sarcomere
- not banding, hence, the name smooth
- no z lines but have dense bodies
Smooth Muscle Cells Classification - ANSWER>>Phasic or Tonic
Multi-unit or single-unit
Neurogenic or myogenic
Phasic - ANSWER>>contracts in burst (hollow organs)
Tonic - ANSWER>>partially contracted at all times (arterioles)
Finals Exam
Muscle - ANSWER>>Highly organized microfilament-based structure
Muscle - ANSWER>>A specialized cell that contracts to pull an external structure
or squeeze a fluid
Muscle - ANSWER>>Can produce a force that can be transmitted over a
considerable distance and can generate large and often rapid movements
Muscle - ANSWER>>Largest group of tissue in the body (most vertebrates)
Muscle - ANSWER>>Can shorten and develop tension from highly developed
microfilament system - enables them to produce force and do work
Muscle - ANSWER>>Converts the chemical energy of ATP into mechanical energy
that can act on the environment in response to electrical signal
Types of Muscles - ANSWER>>Skeletal
Cardiac
Smooth
Functions of Muscles - ANSWER>>1. Emptying of contents of certain organs -
urination and emptying of bile
2. Manipulation of external objects
3. Propulsion of contents
4. Purposeful locomotory movement
5. Production of heat as a metabolic by-product - thermoregulation
6. Production of sound
,Structure of Skeletal Muscle - ANSWER>>Whole muscle - muscle fiber - myofibril -
thick and thin filaments - myosin and actin
William Bowman - ANSWER>>Studied the structure of skeletal muscle in the
1830's using more than 40 animal species
A Band - ANSWER>>consist of a stacked set of thick filaments with a portion of
thin filament that overlap on both ends of the thick filaments
I Band - ANSWER>>consist of remaining portion of the thin filaments that do not
project into the A band
Z Line - ANSWER>>a flat cytoskeletal disc a line visible in the middle of each I band
Sarcomere - ANSWER>>an area between two Z lines (functional unit of a muscle)
H Zone - ANSWER>>the lighter are in the middle of A band where thin filaments
do not reach
M Line - ANSWER>>made up of supporting proteins, extends vertically down the
middle of the A band within the center of H zone
Similarities between Skeletal, Smooth, and Cardiac muscles - ANSWER>>1. both
have specialized contractile apparatus (actin and myosin)
2. Needs calcium for contraction
3. directly uses ATP as energy source of cross-bridge cycling
Differences between Skeletal, Smooth, and Cardiac muscles - ANSWER>>1.
Structure and organization of fibers
2. Mechanism of excitation and contraction
3. Distinction in contractile responses
Skeletal Muscle Cells - ANSWER>>- Striated and voluntary
, - Large, cylindrical, multinucleated
- lies in all skeletal muscles
- extends in the full length of skeletal muscles
- with numerous myofibrils, T tubules, and SR
Smooth Muscle Cells - ANSWER>>- Small and unstriated
- Elongated, spindle-shaped, with single nucleus
- lie in the walls of hollow organs and tubes
- Contraction exerts pressure on and regulates the forward movement of contents
of hollow organs and tubes
- Do not extend to the full length of a muscle
arrange in sheets
3 Types of filaments of Smooth Muscle Cells - ANSWER>>1. Thick myosin
filaments (longer than skeletal muscle)
2. Thin actin filaments with tropomyosin only
3. Filaments of intermediate size (not contractile)
Smooth Muscle Cells - ANSWER>>- Do not form myofibril
- Not arranged in sarcomere
- not banding, hence, the name smooth
- no z lines but have dense bodies
Smooth Muscle Cells Classification - ANSWER>>Phasic or Tonic
Multi-unit or single-unit
Neurogenic or myogenic
Phasic - ANSWER>>contracts in burst (hollow organs)
Tonic - ANSWER>>partially contracted at all times (arterioles)
