These muscles maintain blood pressure and circulation in the event of blood loss or dehydration. They expand to increase blood flow during times of intense exercise when the body requires more oxygen. The diaphragm is a dome-shaped muscle located below the lungs. When the diaphragm contracts, it pushes downward, causing the chest cavity to get bigger.
The lungs then fill with air. When the diaphragm muscle relaxes, it pushes air out of the lungs. When someone wants to breath more deeply, it requires help from other muscles, including those in the abdomen, back, and neck. Smooth muscles in the gastrointestinal or GI tract control digestion. The GI tract stretches from the mouth to the anus.
Food moves through the digestive system with a wave-like motion called peristalsis. Muscles in the walls of the hollow organs contract and relax to cause this movement, which pushes food through the esophagus into the stomach.
The upper muscle in the stomach relaxes to allow food to enter, while the lower muscles mix food particles with stomach acid and enzymes. The digested food moves from the stomach to the intestines by peristalsis.
From here, more muscles contract to pass the food out of the body as stool. Urinary problems, such as poor bladder control or retention of urine, are caused by damage to the nerves that carry signals to the muscles. Did you know you have more than muscles in your body? They do everything from pumping blood throughout your body to helping you lift your heavy backpack. You control some of your muscles, while others — like your heart — do their jobs without you thinking about them at all.
Muscles are all made of the same material, a type of elastic tissue sort of like the material in a rubber band. Thousands, or even tens of thousands, of small fibers make up each muscle. You have three different types of muscles in your body: smooth muscle, cardiac say: KAR-dee-ak muscle, and skeletal say: SKEL-uh-tul muscle. Smooth muscles — sometimes also called involuntary muscles — are usually in sheets, or layers, with one layer of muscle behind the other. You can't control this type of muscle.
Your brain and body tell these muscles what to do without you even thinking about it. You can't use your smooth muscles to make a muscle in your arm or jump into the air. But smooth muscles are at work all over your body. In your stomach and digestive system, they contract tighten up and relax to allow food to make its journey through the body.
Your smooth muscles come in handy if you're sick and you need to throw up. The muscles push the food back out of the stomach so it comes up through the esophagus say: ih-SAH-fuh-gus and out of the mouth. Smooth muscles are also found in your bladder. When they're relaxed, they allow you to hold in urine pee until you can get to the bathroom.
Then they contract so that you can push the urine out. These muscles are also in a woman's uterus, which is where a baby develops. Technically they are all part of the muscular system , they are just three types of muscle tissue. However, we normally think of skeletal muscle as the muscle system, those that make up the bulk of our body. Technically they are all part of the muscular system, they are just three types of muscle tissue. Of smooth, cardiac, and skeletal which one or ones is referred to as the muscular system?
Jun 2, Explanation: Technically they are all part of the muscular system, they are just three types of muscle tissue. Intercalated disks are made up of fingerlike projections from two neighboring cells that interlock and provide a strong bond between the cells. The branched structure and intercalated disks allow the muscle cells to resist high blood pressures and the strain of pumping blood throughout a lifetime. These features also help to spread electrochemical signals quickly from cell to cell so that the heart can beat as a unit.
Skeletal muscle is the only voluntary muscle tissue in the human body—it is controlled consciously. Every physical action that a person consciously performs e. The function of skeletal muscle is to contract to move parts of the body closer to the bone that the muscle is attached to. Most skeletal muscles are attached to two bones across a joint, so the muscle serves to move parts of those bones closer to each other. Skeletal muscle cells form when many smaller progenitor cells lump themselves together to form long, straight, multinucleated fibers.
Striated just like cardiac muscle, these skeletal muscle fibers are very strong. Skeletal muscle derives its name from the fact that these muscles always connect to the skeleton in at least one place. Most skeletal muscles are attached to two bones through tendons.
Tendons are tough bands of dense regular connective tissue whose strong collagen fibers firmly attach muscles to bones. Tendons are under extreme stress when muscles pull on them, so they are very strong and are woven into the coverings of both muscles and bones. Muscles move by shortening their length, pulling on tendons, and moving bones closer to each other. One of the bones is pulled towards the other bone, which remains stationary.
The place on the stationary bone that is connected via tendons to the muscle is called the origin. The place on the moving bone that is connected to the muscle via tendons is called the insertion. The belly of the muscle is the fleshy part of the muscle in between the tendons that does the actual contraction. Skeletal muscles are named based on many different factors, including their location, origin and insertion, number of origins, shape, size, direction, and function.
Skeletal muscles rarely work by themselves to achieve movements in the body. More often they work in groups to produce precise movements.
The muscle that produces any particular movement of the body is known as an agonist or prime mover. The agonist always pairs with an antagonist muscle that produces the opposite effect on the same bones.
For example, the biceps brachii muscle flexes the arm at the elbow. As the antagonist for this motion, the triceps brachii muscle extends the arm at the elbow. When the triceps is extending the arm, the biceps would be considered the antagonist.
Synergists are muscles that help to stabilize a movement and reduce extraneous movements. They are usually found in regions near the agonist and often connect to the same bones. Because skeletal muscles move the insertion closer to the immobile origin, fixator muscles assist in movement by holding the origin stable.
If you lift something heavy with your arms, fixators in the trunk region hold your body upright and immobile so that you maintain your balance while lifting. Skeletal muscle fibers differ dramatically from other tissues of the body due to their highly specialized functions. Many of the organelles that make up muscle fibers are unique to this type of cell.
The sarcolemma is the cell membrane of muscle fibers. The sarcolemma acts as a conductor for electrochemical signals that stimulate muscle cells.
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