Intro to the Muscular System
The muscular system is an organ system consisting of skeletal, smooth and cardiac muscles. It permits movement of the body, maintains posture and circulates blood throughout the body.
The muscular system is an organ system consisting of skeletal, smooth and cardiac muscles. It permits movement of the body, maintains posture and circulates blood throughout the body.
Microscopic Muscle
When muscle cells are viewed under the microscope, one can see that they contain a striped pattern (striations). This pattern is formed by a series of basic units called sarcomeres that are arranged in a stacked pattern throughout muscle tissue (Figure 1). There can be thousands of sarcomeres within a single muscle cell. Sarcomeres are highly stereotyped and are repeated throughout muscle cells, and the proteins within them can change in length, which causes the overall length of a muscle to change. An individual sarcomere contains many parallel actin (thin) and myosin (thick) filaments. The interaction of myosin and actin proteins is at the core of our current understanding of sarcomere shortening. How does this shortening happen? It has something to do with a sliding interaction between actin and myosin.
When muscle cells are viewed under the microscope, one can see that they contain a striped pattern (striations). This pattern is formed by a series of basic units called sarcomeres that are arranged in a stacked pattern throughout muscle tissue (Figure 1). There can be thousands of sarcomeres within a single muscle cell. Sarcomeres are highly stereotyped and are repeated throughout muscle cells, and the proteins within them can change in length, which causes the overall length of a muscle to change. An individual sarcomere contains many parallel actin (thin) and myosin (thick) filaments. The interaction of myosin and actin proteins is at the core of our current understanding of sarcomere shortening. How does this shortening happen? It has something to do with a sliding interaction between actin and myosin.
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Properties of Skeletal Muscle Activity
Skeletal muscle possesses four essential properties:
Skeletal muscle possesses four essential properties:
- Excitability: this refers to muscle tissue being able to react to nervous stimulation.
- Extensibility: this refers to the ability of muscle tissue to lengthen when contracting and provide the effort required to move the lever system (the bones and joints), producing coordinated movement.
- Elasticity: this refers to the ability of muscle tissue to return to its normal resting length once it has been stretched. A useful analogy is that of an elastic band, that will always resume its resting shape after it has been stretched. This property enables the muscle to prepare for a series of repeated contractions, which is normally required when performing exercise or sport.
- Contractility: this refers to the capacity of a muscle to contract or shorten forcibly when stimulated by nerves and hormones (excitability).
Quick Update Message
At the direction of Superintendent Farley, effective immediately, we are not to collect any work from students unless it is collected digitally. If your student has work that needs to be turned in but cannot transmit it electronically, please hold it until we are cleared to collect it. The school has been locked down for disinfection. Thank you for your patience and understanding.
With that being said, for science, those who can send things electronically, I'll be collecting work through Teams. Please go to the Tutorial Unit in the class website to learn how to access it.
Also if you cannot electronically hand things in, please let me know so that I can make a note of it. If I haven’t heard from you yet, I need to hear from you. Please contact me.
At the direction of Superintendent Farley, effective immediately, we are not to collect any work from students unless it is collected digitally. If your student has work that needs to be turned in but cannot transmit it electronically, please hold it until we are cleared to collect it. The school has been locked down for disinfection. Thank you for your patience and understanding.
With that being said, for science, those who can send things electronically, I'll be collecting work through Teams. Please go to the Tutorial Unit in the class website to learn how to access it.
Also if you cannot electronically hand things in, please let me know so that I can make a note of it. If I haven’t heard from you yet, I need to hear from you. Please contact me.
March 26, 2020
Body Movements
In general, motion is classified according to the anatomical plane it occurs in. Flexion and extension are examples of angular motions, in which two axes of a joint are brought closer together or moved further apart. Rotational motion may occur at other joints, for example the shoulder, and are described as internal or external. Other terms, such as elevation and depression, describe movement above or below the horizontal plane. Many anatomical terms derive from Latin terms with the same meaning.
Muscle Naming
Anatomists name the skeletal muscles according to a number of criteria, each of which describes the muscle in some way. These include naming the muscle after its shape, size, fiber direction, location, number of origins or its action.
In general, motion is classified according to the anatomical plane it occurs in. Flexion and extension are examples of angular motions, in which two axes of a joint are brought closer together or moved further apart. Rotational motion may occur at other joints, for example the shoulder, and are described as internal or external. Other terms, such as elevation and depression, describe movement above or below the horizontal plane. Many anatomical terms derive from Latin terms with the same meaning.
Muscle Naming
Anatomists name the skeletal muscles according to a number of criteria, each of which describes the muscle in some way. These include naming the muscle after its shape, size, fiber direction, location, number of origins or its action.
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PowerPoints
Assignments
Assigned 3/26/2020 ~ Body Movements & Naming the Muscles Notes Assignment located in Teams under assignments - Due by 3/30/2020 at 8AM.
Assigned 3/30/2020 ~ Daily Buzz #7 - Due by 3/31/2020 at 8AM
Assigned 3/30/2020 ~ Daily Buzz #7 - Due by 3/31/2020 at 8AM
March 30, 2020
10 Major Muscles of the Body
The major skeletal muscle groups forming the upper body are the abdominal, pectoral, deltoid, trapezius, latissimus dorsi, erector spinae, biceps, and triceps. The major skeletal muscle groups of the lower body are the quadriceps, hamstrings, gastrocnemius, soleus, and gluteus. Muscles move by contracting.
The major skeletal muscle groups forming the upper body are the abdominal, pectoral, deltoid, trapezius, latissimus dorsi, erector spinae, biceps, and triceps. The major skeletal muscle groups of the lower body are the quadriceps, hamstrings, gastrocnemius, soleus, and gluteus. Muscles move by contracting.
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PowerPoints
Games
Assignments
Assigned 3/30/2020 ~ Labeling Muscles Notes - Due 4/1/2020 at 8PM
Assigned 3/30/2020 ~ Daily Buzz #8 - Due by 4/1/2020 at 8PM
Assigned 3/30/2020 ~ Skeletal Muscle Diagramming - Due by 4/3/2020 at 8AM
Assigned 3/30/2020 ~ Skeletal Muscle Games - Due by 4/6/2020 at 8AM
Assigned 3/31/2020 ~ Unit 5 Muscular System Review - Due by 4/7/2020 8AM
Assigned 4/3/2020 ~ Quizizz.com Profile Setup - Due by 4/6/2020 at 11:PM
Assigned 4/6/2020 ~ Muscle Practice Test on Quizizz - Due by 4/7/2020 at 11:45PM
Assigned 4/7/2020 ~ April 8th Unit 5 Test on Quizizz - Due by 4/10/2020 at 11:45PM
Assigned 3/30/2020 ~ Daily Buzz #8 - Due by 4/1/2020 at 8PM
Assigned 3/30/2020 ~ Skeletal Muscle Diagramming - Due by 4/3/2020 at 8AM
Assigned 3/30/2020 ~ Skeletal Muscle Games - Due by 4/6/2020 at 8AM
Assigned 3/31/2020 ~ Unit 5 Muscular System Review - Due by 4/7/2020 8AM
Assigned 4/3/2020 ~ Quizizz.com Profile Setup - Due by 4/6/2020 at 11:PM
Assigned 4/6/2020 ~ Muscle Practice Test on Quizizz - Due by 4/7/2020 at 11:45PM
Assigned 4/7/2020 ~ April 8th Unit 5 Test on Quizizz - Due by 4/10/2020 at 11:45PM