Is muscle tissue electrically active?
Nerve cells and muscle cells are excitable. Their cell membrane can produce electrochemical impulses and conduct them along the membrane. In muscle cells, this electric phenomenon is also associated with the contraction of the cell.
What is the composition of muscle tissue?
Muscle Biochemical Composition Skeletal muscles contain approximately 75% water, 20% protein, 1–10% fat, and 1% glycogen. The biochemical properties of the major muscle components (i.e., myofibers, connective tissue, and adipose tissue) are described in the following.
Does muscle tissue have a nucleus?
Skeletal muscle cells are elongated or tubular. They have multiple nuclei and these nuclei are located on the periphery of the cell. Skeletal muscle is striated. Smooth muscle cells have a single centrally located nucleus.
What is the meaning of striation?
1a : the fact or state of being striated. b : arrangement of striations or striae. 2 : a minute groove, scratch, or channel especially when one of a parallel series. 3 : any of the alternate dark and light cross bands of a myofibril of striated muscle.
Can muscle tissue initiate an electrical impulse?
Like neurons, muscle is an excitable tissue, in that it can conduct or transmit electrical impulses (respond to stimuli).
How do muscle cells respond to electrical impulses?
Muscle contraction begins when the nervous system generates a signal. The signal, an impulse called an action potential, travels through a type of nerve cell called a motor neuron. The chemical message, a neurotransmitter called acetylcholine, binds to receptors on the outside of the muscle fiber.
What are the 3 components of a muscle?
In the muscular system, muscle tissue is categorized into three distinct types: skeletal, cardiac, and smooth.
What cells make up muscle tissue?
Muscle cells, commonly known as myocytes, are the cells that make up muscle tissue. There are 3 types of muscle cells in the human body; cardiac, skeletal, and smooth. Cardiac and skeletal myocytes are sometimes referred to as muscle fibers due to their long and fibrous shape.
Which cells contain Sarcoplasm?
Sarcoplasm is the cytoplasm of a muscle cell. It is comparable to the cytoplasm of other cells, but it contains unusually large amounts of glycogen (a polymer of glucose), myoglobin, a red-colored protein necessary for binding oxygen molecules that diffuse into muscle fibers, and mitochondria.
Do smooth muscles have Myofilaments?
Myofilaments are the two protein filaments of myofibrils in muscle cells. In obliquely striated muscle, the filaments are staggered. Smooth muscle has irregular arrangements of filaments.
What is the electron micrograph of skeletal muscle?
Skeletal Muscle EM. This is an electron micrograph of a longitudinal section of skeletal muscle. First, focus on the components in the different bands. The I-Band contains actin filaments and is bisected by the Z-disk. The A-Band contains myosin and actin filaments. The M-line is a disc-like zone where myosin filaments are crosslinked.
What are the bands on a muscle micrograph?
Muscle: Skeletal and Cardiac Muscle Ultrastructure This is a high power, light micrograph of a muscle fibre showing the banding pattern. There are light stripes – which are called the ‘Z’ lines, and darker wider stripes called the ‘A’ bands. (A – for anisotropic – because in a polarizing light microscope, the dark bands are birefringent)
Why are muscle cells called striated muscle cells?
There are three major types of muscle, and their structure reflects their function. Skeletal and cardiac muscle cells are called striated muscle because of the very regular arrangement of their intracellular contractile units, sarcomeres, at the light microscope (LM) and electron microscope (EM) levels.
How are muscle fibrils and endomysium related?
Chances are, if you are looking at an electron micrograph of muscle tissue, you are looking at myofibrils. Groups of these fibrils form a muscle fiber, which is surrounded by endomysium. Muscle fiber and muscle cell are synonymous.