module 3 Flashcards
Muscle can be categorized morphologically as either _______ or _______.
striated or smooth
Muscles are __________ organs
contractile
what two functions does the muscular system have?
voluntary, walking
involuntary, beating of the heart, breathing, digestion
_________ help the human body move, attached to bones via tendons
Skeletal muscles
________ is found in the heart. It contracts rhythmically, and is modulated by neural activity and hormone
Cardiac muscle
_______ is controlled by the nervous system or hormones. It may be either generally inactive and then respond to stimulation, or it may be rhythmic
Smooth muscle
____________ is marked by both light and dark bands, found in the heart and skeletal muscles
Striated muscle
Striated muscle is characterized by ________ with _________ which are located peripherally for skeletal muscle or centrally for cardiac muscle
long muscle fibres
multiple nuclei
________ is found in blood vessels and the digestive system
Smooth msucle
Each smooth muscle fibre contains a ________ nucleus
single centrally located
________ is muscle that is consciously controlled in order to perform a specific function
Voluntary muscle
_________ is not consciously controlled, consists of smooth muscle and cardiac muscle
Involuntary muscle
The ability of muscle tissue to receive and respond to electrical signals from nerves or stimulation from hormones
Excitability
When a muscle cell is excited by a nerve or hormone, this causes the muscle to shorten, resulting in contraction
Contractility
The ________ is the layer of connective tissue that surrounds an entire muscle and is continuous with the tissue that becomes the tendon.
epimysium
The _________ is the layer of connective tissue surrounding a bundle of muscle fibres within a muscle.
perimysium
The _______ is the layer of connective tissue that surrounds the individual muscle cells within a muscle bundle
endomysium
________ are organized into repeating structural units known as sarcomeres
Myofilaments
When shortened, the_________ cause contraction of the muscle
sarcomeres
Each sarcomeres consists of ______ and ______
actin (thin) and myosin (thick)
The _______ is made up of thick and thin filaments. It appears darker when viewed histologically
A-band
The ______ is composed of protein that makes a ‘zig-zag’ line marking the beginning and end of each sarcomere
Z-line
The _______ is composed of protein down the center of the sarcomere
M-line
The _____ is made up of thin filaments. It appears lighter in colour and transverses two sarcomeres
I-band
Skeletal muscle cells are ___________
multinucleated
__________ are the structural units of the muscle cell and contain the contractile myofilaments
Myofibrils
__________ are the contractile units of the muscle cell.
Myofilaments
Includes bones and muscles associated with the skull, vertebral column (spine), and thoracic cage (ribs and sternum)
Axial
Stabilize and control the movements of the pectoral (shoulder) and pelvic (hip) girdles
Appendicular
The _______ muscles of the thorax aid in the process of breathing.
intercostal
________ are the most superficial, and their fibres run anteriorly and inferiorly between the ribs (inspiration)
External intercostals
______lie deep to the externals, and their fibres run posteriorly and inferiorly (expiration)
Internal intercostals
The _______ is the most superficial of the abdominal wall musculature.
external oblique
The ________ lies deep to the external oblique
internal oblique
The ___________ runs horizontally, deep to the internal oblique.
transversus abdominis
The _________ lies on either side of the linea alba and is separated by tendinous intersection
rectus abdominis
