CAMP.BIO:CONC...MOD.MAST+PRINT>I<
10th Edition
ISBN: 9780136858287
Author: Taylor
Publisher: INTER PEAR
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 30, Problem 18TYK
When a person dies, muscles become rigid and fixed in position—a condition known as rigor. Rigor mortis occurs because muscle cells are no longer supplied with ATP (when breathing stops, ATP synthesis ceases). Calcium also flows freely into dying cells. The rigor eventually disappears because the biological molecules break down. Explain, in terms of the mechanism of contraction described in Modules 30.9 and 30.10, why the presence of calcium and the lack of ATP would cause muscles to become rigid, rather than limp, soon after death.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
For a skeletal muscle to remain rigidly contracted, it needs a continual supply of ATP. Yet, when a skeletal muscle runs out of ATP (in a corpse), it becomes rigid.
How can you explain this seeming paradox?
Explain how skeletal muscle may remain relaxed even if ATP levels are high.
A few hours after the death of an animal, the corpse will stiffen as a result of
continued contraction of muscle tissue (this state is called rigor mortis). This
phenomenon is the result of the loss of ATP production in muscle tissue.
(a) Consult Figure 7.48 and describe, in terms of the six-step model of mus-
de contraction, how a lack of ATP in sarcomeres would result in rigor
mortis.
(b) The Ca* transporter in sarcomeres that keeps the [Ca*)-10-7 M
requires ATP to drive transport of Ca* ions across the membrane of the
sarcoplasmic reticulum. How would a loss of this Ca* transport func-
tion result in the initiation of rigor mortis?
(c) Rigor mortis is maximal at - 12 hrs after death, and by 72 hrs is no longer
observed. Propose an explanation for the disappearance of rigor mortis
after 12 hrs.
Shortly after a person dies, Calcium ions diffuse out of the sarcoplasmic reticulum and the body becomes very stiff and rigid, a phenomenon called rigor mortis (stiffness + death). Given ATP’s role in myosin head movement, propose an explanation for rigor mortis.
Chapter 30 Solutions
CAMP.BIO:CONC...MOD.MAST+PRINT>I<
Ch. 30 - Complete this concept map on animal movement.Ch. 30 - A humans internal organs are protected mainly by...Ch. 30 - Arm muscles and leg muscles are arranged in...Ch. 30 - Gravity would have the least effect on the...Ch. 30 - Prob. 5TYKCh. 30 - Prob. 6TYKCh. 30 - When a dog is running fast, its body position is...Ch. 30 - What is the role of calcium in muscle contraction?...Ch. 30 - Muscle A and muscle B have the same number of...Ch. 30 - Prob. 10TYK
Ch. 30 - Prob. 11TYKCh. 30 - Prob. 12TYKCh. 30 - Prob. 13TYKCh. 30 - Describe how you bend your arm, starting with...Ch. 30 - Prob. 15TYKCh. 30 - Drugs are often used to relax muscles during...Ch. 30 - An earthworms body consists of a number of...Ch. 30 - When a person dies, muscles become rigid and fixed...Ch. 30 - SCIENTIFIC THINKING Imagine you have a friend who...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- If we need ATP for both contraction and relaxation, how would you explain why rigor mortis appears in a dead person, but then goes away?arrow_forwardWhen an animal dies, its limbs and body become stiff because its muscles go into rigor mortis (literally, rigor mortis means “stiffness of death”). Why would the loss of ATP following death cause this to happen?arrow_forwardSkeletal muscle fibres are very metabolically active and are adapted to create a lot of ATP from aerobic cellular respiration. Additionally, cells require other things to stay alive. Explain how the following three organ systems contribute to allowing a muscle cell to carry out its roles: a) Respiratory system b) Cardiovascular system c) Gastrointestinal system asap please.arrow_forward
- Shortly after a person dies, Ca2+diffuses out of the saroplasmic reticulum and the body becomes very still and rigid, a phenomenoncalled rigor mortis (rig′er mōr′tis). Given ATP’s role in myosin head movement, propose an explanation for rigor mortis.arrow_forwardSuppose a person had an unusual mutation in the troponin protein of his skeletal muscles, such that the troponin could not bind to calcium. Would this person’s muscles be constantly contracted, constantly relaxed, or able to function normally? Explain.arrow_forwardMarathon runners often practice "carb loading" prior to a race. The purpose of this practice is to increase the stores of energy available for muscles to use. Explain how energy is used by muscle fibers and how this practice of "card loading" benefits the runner's muscles. Be sure to use the terms glucose, glycogen, creatine, phosphate, and ATP in the explanation.arrow_forward
- Recently, it has been observed that several muscle diseases and disorders are linked to problems with triad structure and function.One such disorder is called malignant hyperthermia, a dire hypermetabolic response to certain inhaled anesthetics such as halothane. Muscles become very rigid due to excessive contraction (especially the masseter muscle), the body temperature spikes, andmuscles break down. Death is certain if not treated. Given the principal symptoms of malignant hyperthermia, what is its likely cause?Propose a theoretical mechanism for a treatment that would dampen the deleterious effects of this disorder.arrow_forwardImpairment of intracellular calcium homeostasis in muscle fibers lead to chronic, severe muscle dysfunction. Impaired Calcium ATPase activity can lead to abnormal, persistent elevation of intracellular calcium concentrations. Explain how persistently high intracellular calcium concentration would affect cross-bridge formation, and muscle contractions, and muscle tension? (Mention the effects on the steps involved cross bridge formation, and muscle contraction/relaxation cycle, and overall muscle tension).arrow_forwardCalmodulin is found in smooth muscle cells and performs a similar function to troponin in striated muscle fibers. However, calmodulin not only gets activated by Ca2+ but also slows the release of Ca2+ from the sarcoplasmic reticulum. How might this difference relate to the different kinds of contractions smooth muscles do in comparison to striated muscles?arrow_forward
- In muscle cells, magnesium ions compete with calcium ions for binding sites on troponin molecules. If a person has too high a concentration of magnesium ions in the blood, magnesium ions can prevent calcium ions from binding troponin. A) What effect would this have on muscle contraction (strengthen, weaken, or no effect)? B) Use your knowledge of how muscle fibers contract to explain your answer in part A.arrow_forwardA muscle is attempting to avoid being eaten by a starfish by tightly closing its shell. Is this an isometric contraction or an isotonic contraction? Explain.arrow_forwardWhich region or organelle—cytosol, mitochondrion, or SR—contains the highest concentration of calcium ions in a resting muscle fiber? Which structure provides the ATP needed for muscle activity?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- 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
Human Physiology: From Cells to Systems (MindTap ...
Biology
ISBN:9781285866932
Author:Lauralee Sherwood
Publisher:Cengage Learning
Human Biology (MindTap Course List)
Biology
ISBN:9781305112100
Author:Cecie Starr, Beverly McMillan
Publisher:Cengage Learning
GCSE PE - ANTAGONISTIC MUSCLE ACTION - Anatomy and Physiology (Skeletal and Muscular System - 1.5); Author: igpe_complete;https://www.youtube.com/watch?v=6hm_9jQRoO4;License: Standard Youtube License