Becker's World of the Cell (9th Edition)
9th Edition
ISBN: 9780321934925
Author: Jeff Hardin, Gregory Paul Bertoni
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 14, Problem 14.3CC
A single myosin II motor domain can exert about 1–5 piconewtons (pN) of force. The gravitational force of 1 kg near Earth’s surface is 9.8 newtons (N). 1 pN = 1.0 × 10−12 N. How is it that myosin can move kilograms of tissue in large animals?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
How fast could a non-muscle cell make a contraction compared to a muscle cell if the relative rates of myosin walks on F-actin are 4.5 μm/sec and 0.04 μm/sec for myosin II and I respectively?
Myosin II has a duty ratio of 10 percent, and its step size is 8 nm. In contrast, myosin V has a much higher duty ratio (about 70 percent) and takes 36-nm steps as it walks down an actin filament. What differences between myosin II and myosin V account for their different properties?
How many actin monomers within an actin filament would a myosin molecule need to ratchet in order to contract a cell by approximately 1 μm?
Chapter 14 Solutions
Becker's World of the Cell (9th Edition)
Ch. 14 - If myosin V moved more like an inchworm (meaning...Ch. 14 - Kinesins and dyneins are both microtubule-based...Ch. 14 - CONCEPT CHECK 14.2 Human sperm swim using a...Ch. 14 - A single myosin II motor domain can exert about 15...Ch. 14 - Prob. 14.4CCCh. 14 - In addition to being found at the rear of...Ch. 14 - Ciliobrevins. Ciliobrevins were reported in 2012...Ch. 14 - Prob. 14.2PSCh. 14 - Prob. 14.3PSCh. 14 - Rigor Mortis and the Contraction Cycle. After...
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
- Describe the movement of myosin along an actin filament. Outline the primary molecular steps and explain how this process is used by cells. How many actin monomers within an actin filament would a myosin molecule need to ratchet in order to contract a cell by approximately 1 um? How fast could a non-muscle cell make this contraction compared to a muscle cell if the relative rates of myosin walks on F-actin are 4.5 um/sec and 0.04 um/sec for myosin II and I respectively?arrow_forwardAs mentioned in class, one additional major use of ATP in skeletal muscle (besides powering the myosin heads) is the recycling of calcium ions back into the sarcoplasmic reticulum after depolarization. The resting concentration of Ca++ in the muscle cell cytoplasm is about 50-100 nM, and the spike concentration after depolarization is about 10-20 μΜ. a) Consider a single sarcomere. What is the number of free calcium ions within the sarcomere at rest? What is the number of free calcium ions after depolarization? b) The major ion pump responsible for calcium ion recycling is SERCA (sarco/endoplasmic reticulum calcium ATPase). SERCA uses one molecule of ATP to pump two calcium ions, and the resting level can be restored in about 10-20 ms. How many molecules of ATP are used in a single sarcomere for pumping calcium in a single "twitch"? c) Assume that a single "twitch" is sufficient to drive one sarcomere from its fully extended length (about 2.5 µm) to its fully contracted length (about 1…arrow_forwardThe sliding-filament model of skeletal-muscle contraction assumes a sliding or slipping of interdigitating filaments of actin and myosin. Electron micrographs show that during contraction the actin and my-osin filaments remain of constant length while the distance between Z lines shortens. Explain how this happens in terms of the molecular structure of the muscle filaments. What is the role of regulatory pro-teins (troponin and tropomyosin) in contraction?arrow_forward
- Certain multi-headed myosins bind cooperatively to actin filaments. The binding interaction is mainly electrostatic in nature, so the presence of additional salt (ions) in solution can interfere with binding; ions will tend to associate with charged residues on the two proteins, blocking electrostatic attractions that would otherwise take place. Briefly describe the expected shape of the binding curve for one of these myosins, and what will happen to the shape when the salt concentration increases.arrow_forwardA typical relaxed sarcomere is about 2.3 μm in length and contracts to about2 μm in length. Within the sarcomere, the thin filaments are about 1 μmlong and the thick filaments are about 1.5 μm long.(a) Describe the overlap of thick and thin filaments in the relaxed and contracted sarcomere.(b) An individual “step” by a myosin head in one cycle pulls the thin filamentabout 15 nm. How many steps must each actin fiber make in one contraction?arrow_forwardThe sarcoplasmic reticulum Ca2+-ATPase, pumps 2 mol Ca2+ out of sarcomeres per mol ATP hydrolyzed.(a) Given the following steady-state concentrations and a membrane potential of 65 mV (inside negative), calculate ΔG for the following activetransport process at 37 °C and pH = 7.4:2Ca2+(in) + ATP + H2O → 2Ca2+(out) + ADP + Pi + H+ATP = 2.6 mM, ADP = 210 μM, Pi = 5.1 mM, Ca2+(in) = 32 mM,Ca2+(out) = 2.2 mM(b) In active muscle the pH can drop below 7.4. Is the reaction above moreor less favorable under these conditions?(c) The activity of the Ca2+-ATPase is regulated reversibly under normalconditions to maintain homeostatic concentrations of Ca2+ inside thesarcomere. However, in a rare genetic disorder, irreversible activation ofthe Ca2+ -ATPase can occur. Assuming 37 °C, pH = 7.4, and the steadystate concentrations for ATP, ADP Pi, and Ca2 +(out) given in part (a),calculate the minimum [Ca2 +] inside a sarcomere that has irreversibly activated Ca2 +-ATPase (i.e., the Ca2 +-ATPase…arrow_forward
- Why is myosin II the only myosin capable of producing contractile force?arrow_forwardA typical relaxed sarcomere is about 2.3 µm in length and contracts to about 2 µm in length. Within the sarcomere, the thin filaments are about 1 um long and the thick filaments are about 1.5 um long. (a) Describe the overlap of thick and thin filaments in the relaxed and contracted sarcomere. (b) An individual "step" by a myosin head in one cycle pulls the thin filament about 15 nm. How many steps must each actin fiber make in one contraction?arrow_forward3.4. About human skeletal muscle contraction, what are the correct statements? PHYSIOLOGY_basic (OJO) A muscle fiber is made by the parallel apposition of sarcomers. Generation of force relies on the formation of cross-bridges between actin and myosin filaments. In the process of contraction, adenosine triphosphate (ATP) is required both to drive the actin-myosin association-dissociation cycle and to recycle calcium back to the endoplasmic reticulum. Each muscle fiber is innervated by one neuron only. T tubules are plasma membrane invaginations of the sarcolemma that allow excitation-contraction coupling.arrow_forward
- Within cells, small organelles containing newly synthesized proteins are transported along microtubules by tiny molecular motors called kinesins. What force does a kinesin molecule need to deliver in order to accelerate an organelle with mass 0.0100 pg (10−17 kg) from 0 to 5.80 μm/s within a time of 10.0 μsarrow_forwardIf a person has a vertical force of 10.25N with a nylon strap of a 2.5cm of width and length of 10cm in the trapezius muscle, how much time does the person need to feel pain in the muscle? How much time is needed to injure or damage the muscle? Must show every mathematical process.arrow_forwardMuscle Contraction In an experiment, the strength of a neural stimulus and the resulting muscle contraction are compared. A single motor neuron that synapses with one muscle fibre is observed in this experiment. One end of the muscle fibre is attached to a mass. The following data were obtained from the experiment. Analyze the data and answer the following questions. Number of Trials Strength of Stimulus (mV) Mass Lifted by Muscle Contraction (g) 1 20 2 40 3 60 50 4 80 50 100 Not Tested 120 50 *note that the voltage applied is positive in order to raise potential from resting to threshold Identify the manipulated, responding and controlled variables in the experiment described above. Strength of Stimulus Number of Muscle Fibre Stimulated Mass Lifted by Muscle Contractionarrow_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 Learning
Human Physiology: From Cells to Systems (MindTap ...
Biology
ISBN:9781285866932
Author:Lauralee Sherwood
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