Concept explainers
Match each numbered item with the most closely related lettered item.
skeletal muscle....................................
To review:
Match the term skeletal muscle to the most closely related descriptions given below:
(a) All epithelia.
(b) Single cell layer.
(c) Urinary bladder.
(d) Cell destroyed.
(e) Connective tissue component.
(f) Unicellular, exocrine gland.
(g) Tendon.
(h) Wandering cell.
(i) Lacunae.
(j) Striated.
Introduction:
Skeletal muscles connect to the skeletal system of the body, which help in the movement of various body parts. These muscles are made up of repeated units of the sarcomere, which in turn are made of proteins-actin and myosin fibers. The functional unit of skeletal muscle, which helps in the contraction and relaxation, is sarcomere.
Explanation of Solution
The actin and myosin filaments are thin and thick filaments, respectively, which slide past each other during contraction and relaxation of the skeletal muscles. The line where actin and myosin overlap is called Z lines forming the dark band. The region between these two Z lines is the sarcomere.
The skeletal muscles are considered to be striated because of the presence of these alternating filaments of actin and myosin. Striated muscle is one of the three categories of muscles other than cardiac and unstriated muscles. These muscles are under voluntary control of somatic nervous system and are responsible for movements of our body parts.
Therefore, it can be concluded that skeletal muscles can be correctly matched with option (j) i.e. striated.
Want to see more full solutions like this?
Chapter 3 Solutions
EBK HUMAN ANATOMY
- In skeletal muscle, the sarcolemma is directly covered by: a) epimysium. b) perimysium. c) endomysium.arrow_forwardThe connective tissue that lies just outside the sarcolemma of an individual muscle cell is called the (a) epimysium, (b) perimysium, (c) endomysium, (d) endosteum.arrow_forwardIntercalated discs and pacemaker cells are characteristic of (a) smooth muscle tissue. (b) cardiac muscle tissue. (c) skeletal muscle tissue. (d) a, b, and c are correct.arrow_forward
- A muscle whose fascicles are arranged at an angle to a central longitudinal tendon has this arrangement: (a) circular, (b) longitudinal, (c) parallel, (d) pennate, (e) convergent.arrow_forwardThe muscle tissue that is striated is (a) skeletal muscle, (b) cardiac muscle, (c) smooth muscle, (d) cardiac and skeletal muscle, (e) all three types of muscle tissue.arrow_forwardWhich of the following statements about smooth muscle is false? (a) Smooth muscle cells are called fibers. (b) Most smooth muscle cells, like cardiac muscle cells, are joined by gap junctions. (c) Smooth muscle cells have a single, centrally located nucleus. (d) Contraction of smooth muscle is stimulated exclusively by involuntary nerves. (e) Smooth muscle tissue found in the wall of hollow organs is arranged in sheets.arrow_forward
- The events during the leg phase of a muscle fiber twitch begin with................ and end with......... Breakdown of ACh/uptake of ACh ACh binds to receptor/ influx of sodium Muscle fiber AP/cross bridge forms ATP binds to myosin/ thin filaments slidesarrow_forwardWhich fiber type would be the most useful in the leg muscles of a long-distance runner? (a) fast glycolytic, (b) slow glycolytic, (c) fast oxidative.arrow_forwardThe sarcolemna of the skeletal muscle contains receptors for ...arrow_forward
- As skeletal muscle contracts, one or more bands of the sarcomere become narrower and disappear, and one or more of them emain the same width. Which bands will change—A, H, or I—and why?arrow_forwardWatch this video (http://openstaxcollege.org/l/micromacro) to learn more about macro- and microstructures of skeletal muscles. (a) What are the names of the “junction points” between sarcomeres? (b) What are the names of the “subunits” within the myofibrils that run the length of skeletal muscle fibers? (c) What is the “double strand of pearls” described in the video? (d) What gives a skeletal muscle fiber its striated appearance?arrow_forwardRicha lost two points on her anatomy exam because she couldn’t answer why one type of muscle fiber is red in color, while another type is pale. Explain to her the reason behind the difference in color.arrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage LearningHuman Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning