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Muscular System
The muscular system allows humans to move. Muscles also provide strength, balance and heat.
11,239 Questions
What muscle is known responsible for opening and closing body cavities and openings?
Sphincters control the opening and closing between certain body cavities. These are typically one direction, to prevent backflow, for example. Other body systems, like the blood vessels and heart, use valves, but valves and sphincters have very similar functions (though with major differences too).
A myosin hooks onto and pulls against a partner protein called?
When a skeletal muscle contracts, a protein called a myosin hooks onto and pulls against a "partner" protein called
A. actin.B. a sarcoplasm.C.myofibril.D. a sarcomere.
the answer is A actin
1) Gluteus Maximus
2)Latissimus Dorsi
3) Sartorius
i cant seem to find any larger ones sorry, the gluteus maximus is the largest, the latissimus dorsi is the longest, the sarorious is the widest
Are lymphocytes one of the body's first-line defense against infection?
Yes, the lymphocytes (more commonly known as white blood cells) are a major component of the body's immune system. It is very complex with numerous members that all play important roles (some of which are the B cells, macrophages, helper T cells, cytotoxic T cells, dendritic cells, eosinophil, basophil and neutrophil).
Parts and functions of smooth muscle?
Smooth muscle cells contain filaments called actin and myosin that extend the lengths of the cells, but these filaments are organized differently than striated muscle. Smooth muscle cells lack striations and appear "smooth" under the
microscope. There are two types of smooth muscle. They are multiunit and visceral. The multiunit are not found in sheets. This found in the irises of the eye and in blood vessels. They respond to nerve stimulation and some hormones.
Visceral smooth muscles are found in sheets and they are found in hollow organs. They stimulate each other forming waves. These don't tire easily and do not lose pressure when distended.
Why do football players wear armbands on their biceps?
Those narrow straps are to prevent tendinopathy. By taking some of the load off the muscles and tendons near their attachment points they reduce the likelihood of tearing, particularly of the triceps tendon when falling on the hands. Physical therapists give these to the players to prevent lateral and medial epicondylitis and outright rupture injury and keep them in the game with less pain. That and alot of people, my self included where it because it looks good.
Where in the human body is smooth muscle tissue?
Yes, it is found in the tunica media layer of blood vessels.
How does skeletal muscle move?
Muscles contract to move bones. Bones and muscles work like ropes and levers. The muscles can only pull against the bone not push it. So to bend your arm at the elbow, the bicep pulls the lower arm up. To streighten your arm, the tricep pulls the lower arm back out. the muscles have to work in pairs opposite each other to make movement.
when they contract or pull the bone
I shall use the biceps brachii group as an example in order to answer this question. When the long head of the biceps brachii contracts (in other words, when it shortens) it pulls the point of insertion towards the point of origin (in this case the biceps brachiis point of insertion is at the bicipital aponeurosis and the radial tuberosity, the point of origin is the supraglenoid tubercle of the scapula (for the long head)). This action is known as flexion, or when the angle at a joint decreases. When the angle at a joint increases it is called extension. There are various other types of movement including rotation, abduction and adduction. In order to move any part of your body you must use several different muscles. There are around 639 skeletal muscles in the human body, so the muscles of the body are divided into 16 simple groups:
- Abdominals
- Adductors
- Dorsal muscles
- Shoulders
- Arm extensors
- Wrist extensors
- Gluteals
- Arm flexors
- Wrist flexors
- Scapulae fixers
- Thigh flexors
- Lumbar muscles
- Surae
- Pectorals
- Quadriceps
- Trapezii
Each of these groups is devoted to performing movement in various joints around the body. Since many muscles of the body have opposing actions, it would be impossible for two opposing muscles to perform their action. The body cleverly devised a system whereby when one muscle works its opposing muscle relaxes. The muscle that contracts is called the agonist and the muscle that relaxes, yet still undergoes partial contraction, is called the antagonist.
Now, back to your original question. I shall use walking as an example of moving and then describe how the muscles function to perform this action. In order to walk we bring one of our legs in front of us and then we bring the other foot off the ground and bring that one in front of us and so forth. Walking uses the quadriceps muscle group (the muscles on the front of your thigh), the gluteal muscle group (the muscles located around your backside) and thigh flexor muscle group (the muscles colloquially known as your hamstrings, at the back of your thigh), there are various other assisting muscles also involved in this action. When you extend your leg out in front of you, you are contracting your quadriceps, and when you bend your knee, you are contracting your thigh flexors. The glutealmuscles are responsible for supporting the quadriceps when the leg is straight.
That is how skeletal muscles allow your body to move. As I mentioned earlier, every movement that you can do involves similar events, as described in the previous paragraph.
Most muscles are attached to bones which provide the framework for the human body. When muscles contract (shorten), they pull the skeleton in the direction they shorten. You can often see them bulge when they do so.
What are the requirements of muscle contraction?
Essential elements (as in elements pharmacologically) would be Na (Sodium) and Ca (Calcium) - not including Chlorine as muscle twitches occur without innovation of somatic motor neuron. If your not talking about a twitch you may possibly also include chlorine..
The influx of Na (sodium) into the muscle cell initiates the muscle's generation of an Action potential, which then travels down the T-Tubules, triggering the influx of Ca (Calcium) into the sarcomere (muscle cell cytoplasm). The Ca then binds to tropoponin (receptors on tropomyosin) which the 'calcium tropoponin' complex then pulls the tropomyosin causing the revealance of Myosin binding site. ATP comes and causes myosin heads to lift and bind to actin - filaments move toward M line - u have a muscle contraction.
What are the muscles of the human leg?
There are many muscles in the legs. The main muscle groups are the quads, (front thigh) Hamstrings, (rear thigh) calves ( below knee, mainly behind shin).
These are all made up of a lot of smaller muscle heads. Also, the Glutes (butt) and hip flexors that surround your hips are integral to any leg movement.
Does muscle tissue stabilize joints?
no they just allow movement in joints with out damaging the bones.
Insertion site for the biceps brachii?
It inserts, by means of a tendon, into radial tuberosity on the radius. And then by an aponeurosis, bicipital aponeurosis, which fuses with the adjoining deep fascia.
What is the antagonistic muscle if the vastus intermedius is the agonist muscle?
i think it is the vastus lateralis but im not sure
What is the medical term meaning abnormal softening of muscle tissue?
Myomalacia is pathological softening of the muscles. (myo- means muscle, -malacia means abnormal softening).
Often confused similar words include:
Myelomalacia is a pathological term referring the softening of the spinal cord.
Myonecrosis is death of muscle cell fibers.
malacia
Which part of the body has the gluteus maximus muscle and the largest single muscle?
A person's buttocks (bottom; rear-end) contains the gluteus maximus muscle and the largest single muscle.
The teacher tersely told the student to sit on his gluteus maximus and be quiet!
What corresponding muscle does leg raises go to?
Abductor muscle - moves a limb away from the midline
Adductor muscle - moves a limb towards the midline
Extensor muscle - increase the angle at a joint - extends a limb
Flexor muscle - decreases the angle at a joint - flexes a limb
Pronator muscle - turns a limb to face downwards
Supinator muscle - turns a limb to face upwards
Rotator muscle - rotates a limb
In the human body, these are the responsible muscles.
*Muscles which move the thigh and their action*
Gluteus maximus - Extends and rotates thigh laterally.
Adductor longus - Adducts, medially rotates and flexes the thigh
Adductor brevis - Adducts, laterally rotates and flexes the thigh
Adductor magnus - Adducts, flexes, laterally rotates and extends the thigh.
Rectus femoris - Extends knee and flexes hip
Vastus lateralis - Extends knee
Vastus medialis - Extends knee
Vastus intermedius - Extends knee
Sartorius - Flexes knee. Flexes hip and rotates femur laterally
Biceps femoris - Flexes leg and extends thigh
Semitendinosus - Flexes leg and extends thigh
Semimembranosus - Flexes leg and extends thigh
