Below L2. the vertebral canal is occupied by a bundle of spinal nerve roots called
- a. the terminal filum.
- b. the descending tracts.
- c. the gracile fasciculus
- d. the medullary cone.
- e. the cauda equina.

Introduction:
Spinal cord is a collection of nerve tissue that arises from the brain stem.
Answer to Problem 1TYR
Correct answer:
Below L2, the vertebral canal is occupied by a bundle of spinal nerve roots called the cauda equina. Therefore, option e is correct.
Explanation of Solution
Justify reasons for the correct statement:
Cauda equina is a collection of spinal nerves at the first lumbar vertebra and medullary cone. It occupies the vertebral canal from L2 to S5.
Option (e) is given as “the cauda equina”.
Cauda equina has approximately 10 fiber pairs that consist of 3 to 5 lumber fibers, 5 sacral fiber pairs, and 1 one coccygeal nerve. The cauda equina functions as to send and receive messages from the pelvic and the lower limbs.
Hence, option (e) is correct.
Justify reasons for the incorrect statements:
Option (a) is given as “the terminal filum”.
It is a delicate fibrous tissue or terminal thread that precedes downward from the apex of the conus medullaris. Hence, it is a wrong answer.
Option (b) is given as “the descending tracts”.
The descending tracts are motor signals that carry the signals from the brain to lower motor neurons. Hence, it is a wrong answer.
Option (c) is given as, “the gracile fasciculus”.
It carries signals from the mid-thoracic and lower parts of the body. Hence, it is a wrong answer.
Option (d) is given as “the medullary cone”.
The medullary cone or the conus medullaris occurs at the lumbar vertebral level 1 and level 2. Hence, it is a wrong answer.
Hence, options (a), (b), (c), and (d) are incorrect.
In conclusion, the cauda equina is a collection of spinal nerve that occurs below the lumbar vertebral level 2 and occupies from L2 to S5.
Want to see more full solutions like this?
Chapter 13 Solutions
ANTOMY AND PHYSIOLOGY
Additional Science Textbook Solutions
Biological Science (6th Edition)
Genetics: From Genes to Genomes
Campbell Essential Biology (7th Edition)
HUMAN ANATOMY
Physics of Everyday Phenomena
Biology: Life on Earth with Physiology (11th Edition)
- This entire structure using lifecycle terminology is called what? megastrobilus microstrobilus megasporophyll microsporophyll microsporangium megasporangium none of thesearrow_forwardHow much protein should Sarah add to her diet if she gets pregnant? Sarah's protein requirements during pregnancy would be higher. See Hint B2. During calculations, use numbers rounded to the first decimal place. In your answer, round the number of grams to the nearest whole number. _______ g ?arrow_forwardC MasteringHealth MasteringNu X session.healthandnutrition-mastering.pearson.com/myct/itemView?assignment ProblemID=17396422&attemptNo=1&offset=prevarrow_forwardMost people, even those who exercise regularly at low to average intensity (1 hour at the gym or a 2- to 3-mile walk several times per week), do not need an increased protein intake. What would be the protein needs of a man named Josh who exercises moderately and is the same age and size as Wayne? Josh is 5 ft, 8 in tall and weighs 183 lb. Round the number of grams to the nearest whole number. During calculations, use numbers rounded to the first decimal place. Because protein requirement is a range, please enter two numbers: lower and upper range values, respectively. Separate the lower and upper range values, in that order, by a comma. ___, ___ g ?arrow_forwardC MasteringHealth MasteringNu X session.healthandnutrition-mastering.pearson.com/myct/itemView?assignment ProblemID=17396422&attemptNo=1&offset=prevarrow_forwardIf left untreated, most HIV-infected individuals will develop AIDS. Current treatments are focused on highlyactive antiretroviral therapy (HAART). HAART usually consists of an orally delivered drug cocktail containingtwo different reverse transcriptase inhibitors and one other drug, such as a protease inhibitor. Question: Develop a pharmacokinetic model of HAART treatment. Consider all 3 drugs. Make sure to include adiagram that illustrates your thinking, state all assumptions, and define your variables. Whatparameters would you need to know to find the concentration of drug in the plasma? In the T cells?(You do not need to write out or solve any equations.)arrow_forwardnot use ai pleseaarrow_forward(A) 25 20 20 15 NPP (Mg C/ha/yr) 10 10 5 0 0 2,000 4,000 6,000 ECOLOGY 4e, Figure 20.11 (Part 1) 2017 Sinauer Associates, Inc. Average annual precipitation (mm) 8,000arrow_forwardexplain the cascade of events (starting with relaxing trade winds) that occurs during El Niño in the eastern Pacific (off the coasts of California/North America and Peru/South America) and which lead to food-chain collapse - start with changes in the physical/oceanographic conditions, andthen systematically describe the cascading effects at each level of the food chain -arrow_forward3) Which statement(s) about the Pacific Decadal Oscillation (PDO) is/are TRUE? CIRCLE ALL THAT APPLY. A. It is a major driver of salmon populations in the Pacific B. It affects sea surface temperatures in the eastern Pacific C. Its cycles typically do not last as long as those of ENSO D. Evidence that it has occurred over many centuries has been gathered from tree ring dataarrow_forward4.arrow_forward2arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_iosRecommended textbooks for you
- Fundamentals of Sectional Anatomy: An Imaging App...BiologyISBN:9781133960867Author:Denise L. LazoPublisher:Cengage LearningMedical Terminology for Health Professions, Spira...Health & NutritionISBN:9781305634350Author:Ann Ehrlich, Carol L. Schroeder, Laura Ehrlich, Katrina A. SchroederPublisher:Cengage Learning
- Anatomy & PhysiologyBiologyISBN:9781938168130Author:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark WomblePublisher:OpenStax CollegeBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning
Fundamentals of Sectional Anatomy: An Imaging App...BiologyISBN:9781133960867Author:Denise L. LazoPublisher:Cengage LearningMedical Terminology for Health Professions, Spira...Health & NutritionISBN:9781305634350Author:Ann Ehrlich, Carol L. Schroeder, Laura Ehrlich, Katrina A. SchroederPublisher:Cengage LearningAnatomy & PhysiologyBiologyISBN:9781938168130Author:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark WomblePublisher:OpenStax CollegeBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning