Anatomy MMS: Muscles Flashcards
What does the muscular system consist of?
Consists of muscles that contract to move parts of the body
What can muscles move?
Muscles can move the limbs and trunk and internal organs
What do muscles give shape to and provide?
Muscles give shape to the body and provide heat
What do associated connective tissue bind?
Associated connective tissue bind muscle fibres together and conveys vessels and nerves
What are the 3 types of muscles?
- Skeletal muscle
- Cardiac muscle
- Smooth muscle
What is the structure of cardiac muscle?
-Striated muscle
What do cardiac muscle form ?
Forms most of the walls of the chambers of the heart
What intrinsic ability do cardiac muscles have?
Has intrinsic ability to contract
What are cardiac muscles resistant to?
Resistant to fatigue
What is the structure of smooth muscle?
- Unstriated
- Visceral
Where are smooth muscle found?
Found in the walls of vessels and hollow organs
What do smooth muscles undergo and to do what?
Undergo peristaltic contractions to move contents
What is the structure of skeletal muscle?
-Striated in appearance
What are skeletal muscles involved in?
Involved in locomotion and movement of joints
What do skeletal muscle consist of?
Consists of bundles of elongated cylindrical cells called muscle fibres
What are muscle fibres and what do they contain?
Muscle fibres are multinucleated and contain a number of myofibrils
What are skeletal muscle surrounded by?
Surrounded by sarcolemma
What do skeletal muscle contain?
Contain sarcoplasm and contractile myofibrils
Classification of muscles
Attachments:
Origin
The origin is the attachment site that doesn’t move during contraction
Classification of muscles
Attachments:
Insertion
Insertion is the attachment site that does move when the muscle contracts.
what is the muscle belly?
It is the sum of all the muscle fibers in any given muscle
What is the aponeurosis?
Aponeurosis, a flat sheet or ribbon of tendonlike material that anchors a muscle or connects it with the part that the muscle moves.
What do tendons do?
Attach muscle to bone
What do tendons allow muscle to be?
Allow muscle bulk to be situated away from its site of action
What can tendons withstand?
Can withstand compression
What do tendons reserve and resist?
Reserve energy and resist heat
What are the ways that muscle can be described?
Muscles can be described by:
- The orientation of the muscle fibres
- Their action
- Their shape
- Their position in the body
- The number of heads
Muscle types:
- Unipennate
- Bipennate
- Multipennate
- Unipennate is having the fibers arranged obliquely and inserting into a tendon only on one side
- Bipennate is having the fibers arranged obliquely and inserting on both sides into a central tendon
- Multipennate is where the diagonal muscle fibers are in multiple rows with the central tendon branching into two or more tendons
What are flexors and extensors also known as?
Hint:the way they behave
Flexors are agonists
Extensors are antagonists
LOOK AT SLIDES FOR CLASSIFICATIONS
LOOK AT SLIDES FOR CLASSIFICATIONS
What are many limb muscles organised into?
Many limb muscles are organised into compartments
What are muscle compartments surrounded by?
Muscle compartments are surrounded by a sleeve of deep fascia
What does each muscle compartment usually have of its own?
Each compartment usually has its own nerve and blood supply
What is venous return aided by in muscle compartments?
Venous return is aided by the pressure from the connective tissue sleeve when the muscles contract
What do muscle in compartments usually work together to do?
Muscles in a compartment usually work together to produce movement
What can trauma to the leg produce, why and what can this cause?
- Trauma to the leg can produce hemorrhage or inflammation
- Because the fascia surrounding the compartment is strong, swelling causes an increase in pressure within the compartment
- This can cause compression
- Distal structures can become ischaemic
