The contractile unit consists of myofibrils which encompass repeating units of sarcomeres running end to end giving a striated appearance to the muscle. Each sarcomere is characterized by two z-lines, one M-line, an A-band and an H-zone. Actin and myosin are the principle proteins in the contractile machinery with myosin dominating the A-band. The latter refracts plane polarized light (anisotropy) giving a dark appearance to
C) sarcoplasmic reticulum. D) myofibril. E) myofilament. 8) Which of the following best describes the term sarcomere? A) protein that accounts for elasticity of resting muscle B) repeating unit of striated myofibrils C) storage site for
Excitability: The ability of muscle tissue to receive a stimulus from the nervous system. Contractility: The quality that distinguishes muscle tissue from other types of tissue. 2.) Name the three types of muscle tissue found in the human body and briefly describe the primary function of each. Skeletal muscle: attached to the bones of the skeletal system.
C. How are the chemical signals of insulin and glucagon received by the target cells? D. Explain the causes of diabetes mellitus type I and type II. (1) Answer A: Prolonged stress is conveyed to neurons in the hypothalamus of the brain. The hypothalamus produces a releasing hormone, which is secreted into the blood supply of the anterior pituitary gland. This causes the anterior pituitary gland to produce and secrete a hormone (adrenocorticotropic hormone) that travels through the circulatory system.
This could be in the form of a liquid, like blood. The matrix is usually secreted by connective tissues. There are connective tissues in blood, cartilage, bone, areolar tissues and adipose tissues. The blood transports materials, areolar gives support to the tissue, and as does cartilage, the bone strengthens and protects. Many different tissues are made of different fibres which are secreted by the cell to provide characteristics.
The muscles interact in a cycle that begins with the myosin head attached to an actin fragment. The movement cannot happen until a nerve impulse releases magnesium ions which then bind to tropomyosin. Tropomyosin is a blocker protein that which blocks the interaction of actin and myosin. When magnesium binds to this protein it changes the shape of it and allows the reaction to proceed. Once
Which muscle type has the most elaborate connected tissue wrapping? Skeletal muscle 3. What is the striated mean relative to muscle cells? Stripped or having bands striated 4. How do the movements promoted from skeletal muscle smooth muscle?
RSQC2 Worksheet Directions: Fill in the blanks below. Identify the following parts of a neuron (need an image): (dendrites, axon, terminal buttons, myelin sheath) Dendrites: The cluster of fibers at one end of the cell body that receive messages from other neurons. Axon: The slim, tube-like extension of the cell body that carries messages from the dendrites to other neurons. Terminal buttons: The small bulges at the end of the axon which send messages to other neurons. Myelin sheath: A protective coating of fat and protein that insulates the axon.
Multiple organ systems make the organism. You are an organism. You have nervous systems, digestive systems, cardiovascular systems etc. Your digestive system is made of several organs such as your tongues, eyes, esophagus, stomach, small intestine, large intestine, etc. To be a living things need to breath, need shelter, water, food, air, roomy environment, etc.
It’s broken down into the somatic nervous system and the autonomic nervous system. The somatic nervous system consists of nerves that provide voluntary control over skeletal muscle contraction. The autonomic nervous system consists of sympathetic and parasympathetic nerves that provide involuntary control over smooth muscle, cardiac muscle, and gland activity and secretions. One is thought of as the accelerator and the other, the brake; or “fight or flight” and “rest and digest” respectively. The sympathetic nerves increase the heart rate, constrict blood vessels to raise blood pressure, and elicit a “fight or flight” response.