Introduction to the Muscular System
In both vertebrates and invertebrates, movement occurs through the muscular system whereby different pairs of groups of muscles pull across joints in different directions causing muscles to contract. The muscular system also functions in responding to stimuli and posture.
In less complex organisms, such as invertebrates, a muscle fiber consisting of two types of filaments, one thick and another thin, that work together by attaching to create a sliding movement between the filaments resulting in muscle tension, thus causing the muscle to contract.
Muscular tissue in vertebrates is connected to the skeletal system and can make up a large amount of body mass. A muscle consists of skeletal muscle tissue, blood vessels, tendons, and nerves.
There are three types of muscle tissue:
1. Skeletal – most are attached to two bones across a joint allowing bones to move and controls voluntary movement and physical action
2. Smooth – located inside organs and blood vessels and allows organs to contract to move substances
3. Cardiac – located only in the heart and its function is to pump blood throughout the body
Muscles are classified as follows:
· Color
Red – high vascularized & resist fatigue
White – low vascularization & quicker to fatigue
· Location
Somatic – move bone or cartilage
Visceral – control activities of organs, vessels, or ducts
· Nervous system control
Voluntary
Involuntary
· Embryonic organ
· General appearance
Skeletal
Smooth
Cardiac
In both vertebrates and invertebrates, movement occurs through the muscular system whereby different pairs of groups of muscles pull across joints in different directions causing muscles to contract. The muscular system also functions in responding to stimuli and posture.
In less complex organisms, such as invertebrates, a muscle fiber consisting of two types of filaments, one thick and another thin, that work together by attaching to create a sliding movement between the filaments resulting in muscle tension, thus causing the muscle to contract.
Muscular tissue in vertebrates is connected to the skeletal system and can make up a large amount of body mass. A muscle consists of skeletal muscle tissue, blood vessels, tendons, and nerves.
There are three types of muscle tissue:
1. Skeletal – most are attached to two bones across a joint allowing bones to move and controls voluntary movement and physical action
2. Smooth – located inside organs and blood vessels and allows organs to contract to move substances
3. Cardiac – located only in the heart and its function is to pump blood throughout the body
Muscles are classified as follows:
· Color
Red – high vascularized & resist fatigue
White – low vascularization & quicker to fatigue
· Location
Somatic – move bone or cartilage
Visceral – control activities of organs, vessels, or ducts
· Nervous system control
Voluntary
Involuntary
· Embryonic organ
· General appearance
Skeletal
Smooth
Cardiac