
Concept explainers
Introduction:
Muscles are defined as soft tissues that are found in humans and animals. There are three types of muscles found in humans such as skeletal muscle, cardiac muscle, and smooth muscle. It contains filament protein such as actin and myosin that are responsible for the contraction of the muscle. Muscles also help to produce force and motion.

Answer to Problem 1MC
Correct answer:
Structures that range from largest to smallest are muscle, muscle fiber, myofibril, thick and thin filaments. Therefore, option (d) is correct.
Option (d) is given as “muscle, muscle fiber, and myofibril, thick and thin filaments”.
Explanation of Solution
Justify reasons for the correct statement:
Muscle cells are soft tissue and are composed of thick and thick filaments that are attached to each other and form cross-bridge and cause muscle contraction. Muscle fibers are surrounded by a plasma membrane called sarcolemma and they also contain cytoplasm called sarcoplasm. Each muscle fiber contains parallel cylindrical myofibrils and is found in striated muscle. Muscle fibers contain multinucleated cells and these cells combine together to form muscle. Myofibril is surrounded by specialized reticulum called sarcoplasmic reticulum. The thick and thin filaments are myosin and actin. Actin filament contains two accessory proteins such as troponin and tropomyosin.
Hence, option (d) is correct.
Justify reasons for the incorrect statements:
Option (a) is given as “motor unit, muscle, myofibril, muscle fiber, thick and thin filament”.
Motor unit is formed when motor neuron synapses with multiple muscle fibers in a single muscle. It consists of motor neuron and skeletal muscle fibers. Hence, it is a wrong answer.
Option (b) is given as “muscle, muscle cell, myofibril, muscle fiber, actin, and myosin”.
Muscle is a part of the skeletal system which includes all the structures such as muscle cell, myofibril, muscle fiber, and actin and myosin filament. Hence, it is a wrong answer.
Option (c) is given as “muscle cell, thick and thin filaments, sarcomeres, myofibril”.
Muscle cell, thick and thin filaments, sarcomeres and myofibril are the structures that together form a muscle cell. Hence, it is a wrong answer.
Hence, options (a), (b), and (c) are incorrect.
Muscle is a soft tissue, which is made of myofibrils, muscle cells, and fibers, a thick and thin filament such as actin and myosin.
Want to see more full solutions like this?
Chapter 41 Solutions
Pearson eText Biology: Life on Earth with Physiology -- Instant Access (Pearson+)
- You have identified a new species of a Gram-positive bacteria. You would like to screen their genome for all proteins that are covalently linked to the cell wall. You have annotated the genome, so that you identified all the promoters, operons, and genes sequences within the operons. Using these features, what would you screen for to identify a set of candidates for proteins covalently linked to the bacterial cell wall.arrow_forwardBelow is a diagram from a genomic locus of a bacterial genome. Each arrow represents a coding region, and the arrowheads indicate its orientation in the genome. The numbers are randomly assigned. Draw the following features on the diagram, and explain your rationale for each feature: 10 12 合會會會會長 6 a) Expected transcriptions, based on known properties of bacterial genes and operons. How many proteins are encoded in each of the transcripts? b) Location of promoters (include rationale) c) Location of transcriptional terminators (include rationale) d) Locations of Shine-Dalgarno sequences (include rationale)arrow_forwardSample excuse letter in school class for the reasons of headaches and dysmenorrhea caused by menstrual cyclearrow_forward
- How do the muscles on the foot work to balance on an ice skate, specifically the triangle of balance and how does it change when balancing on an ice skate? (Refer to anatomy, be specific)arrow_forwardWhich of the following is NOT an example of passive immunization? A. Administration of tetanus toxoid B. Administration of hepatitis B immunoglobulin C. Administration of rabies immunoglobulin D. Transfer of antibodies via plasma therapyarrow_forwardTranscription and Translation 1. What is the main function of transcription and translation? (2 marks) 2. How is transcription different in eukaryotic and prokaryotic cells? (2 marks) 3. Explain the difference between pre-mRNA and post-transcript mRNA. (2 marks) 4. What is the function of the following: (4 marks) i. the cap ii. spliceosome iii. Poly A tail iv. termination sequence 5. What are advantages to the wobble feature of the genetic code? (2 marks) 6. Explain the difference between the: (3 marks) i. A site & P site ii. codon & anticodon iii. gene expression and gene regulation 7. Explain how the stop codon allows for termination. (1 mark) 8. In your own words, summarize the process of translation. (2 marks)arrow_forward
- In this activity you will research performance enhancers that affect the endocrine system or nervous system. You will submit a 1 page paper on one performance enhancer of your choice. Be sure to include: the specific reason for use the alleged results on improving performance how it works how it affect homeostasis and improves performance any side-effects of this substancearrow_forwardNeurons and Reflexes 1. Describe the function of the: a) dendrite b) axon c) cell body d) myelin sheath e) nodes of Ranvier f) Schwann cells g) motor neuron, interneuron and sensory neuron 2. List some simple reflexes. Explain why babies are born with simple reflexes. What are they and why are they necessary. 3. Explain why you only feel pain after a few seconds when you touch something very hot but you have already pulled your hand away. 4. What part of the brain receives sensory information? What part of the brain directs you to move your hand away? 5. In your own words describe how the axon fires.arrow_forwardMutations Here is your template DNA strand: CTT TTA TAG TAG ATA CCA CAA AGG 1. Write out the complementary mRNA that matches the DNA above. 2. Write the anticodons and the amino acid sequence. 3. Change the nucleotide in position #15 to C. 4. What type of mutation is this? 5. Repeat steps 1 & 2. 6. How has this change affected the amino acid sequence? 7. Now remove nucleotides 13 through 15. 8. Repeat steps 1 & 2. 9. What type of mutation is this? 0. Do all mutations result in a change in the amino acid sequence? 1. Are all mutations considered bad? 2. The above sequence codes for a genetic disorder called cystic fibrosis (CF). 3. When A is changed to G in position #15, the person does not have CF. When T is changed to C in position #14, the person has the disorder. How could this have originated?arrow_forward
- hoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forwardhoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forward7. Aerobic respiration of a protein that breaks down into 12 molecules of malic acid. Assume there is no other carbon source and no acetyl-CoA. NADH FADH2 OP ATP SLP ATP Total ATP Show your work using dimensional analysis here: 3arrow_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
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax CollegeComprehensive Medical Assisting: Administrative a...NursingISBN:9781305964792Author:Wilburta Q. Lindh, Carol D. Tamparo, Barbara M. Dahl, Julie Morris, Cindy CorreaPublisher:Cengage LearningBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax





