
To review:
The need for the two different mechanism for the formation of neural tube in relation to the evolutionary pressures that forced the adoption of secondary neurulation. The idea which influence the timing of end of gastrulation and its capacity for axis elongation in relation to neurulation.
Introduction:
The set of morphogenetic events that leads to the formation of neural tube is known as neurulation. This process acts as a base for the formation of central nervous system in different organism. Neurulation is characterized as a complex set of cell movements which includes epithelial columnarization, migration, intercalation and convergent extension. Multiple genes are involvesd in regulation of this process. Neurulation is accompained by two modes, primary neurulation and secondary neurulation.

Explanation of Solution
The formation of vertebral neural tube into anterior and posterior tube are two independent processes specific in morphogenetic and molecular processes. The anterior tube forms by primary neurulation, in contrast posterior tube forms via secondary neurulation. The main difference between these two processes is the role of epithelial and mesenchymal cell population. Epithelial tissues are an organized and continuous sheet of cells associated by junctional complexes whereas the mesenchymal tissue are loosely connected cells.
The evolutionary studies indicate that the mechanism of primary neurulation was the ancestral condition and the secondary neuraltion is evolved later like the evolution of limbs. Before the formation of neural tube, primary neurulation uses a flat neural plat whereas the secondary neurulation starts with a mesenchymal cell population which later condensed. The comparision of early stages serve to evaluate the evolutionary conservation. The precise movement in different vertebrates, shows a number of solutions to the problem of change in neural plate cells into a neural tube. So the morphological and antamoical changes with due course of time may be a reason for the evolution of secondary neurulation. The neural induction, at any given time during gastrulation is regulated by the different cells at the organizer and under the control of precise gene regulation. The cell division in the neural plate is preferentially in anterior-posterior direction, which also regulates the axis elongation during gastrulation.
Thus it is concluded that primary neurulation was the ancestral condition and the secondary neuraltion is evolved later like the evolution of limbs. The comparision of early stages serve to evaluate the evolutionary conservation. The precise movement in different vertebra may be a reason for this evolutionary condition.
Want to see more full solutions like this?
Chapter 13 Solutions
Developmental Biology
- Which of the following is not a DNA binding protein? 1. the lac repressor protein 2. the catabolite activated protein 3. the trp repressor protein 4. the flowering locus C protein 5. the flowering locus D protein 6. GAL4 7. all of the above are DNA binding proteinsarrow_forwardWhat symbolic and cultural behaviors are evident in the archaeological record and associated with Neandertals and anatomically modern humans in Europe beginning around 35,000 yBP (during the Upper Paleolithic)?arrow_forwardDescribe three cranial and postcranial features of Neanderthals skeletons that are likely adaptation to the cold climates of Upper Pleistocene Europe and explain how they are adaptations to a cold climate.arrow_forward
- Biology Questionarrow_forward✓ Details Draw a protein that is embedded in a membrane (a transmembrane protein), label the lipid bilayer and the protein. Identify the areas of the lipid bilayer that are hydrophobic and hydrophilic. Draw a membrane with two transporters: a proton pump transporter that uses ATP to generate a proton gradient, and a second transporter that moves glucose by secondary active transport (cartoon-like is ok). It will be important to show protons moving in the correct direction, and that the transporter that is powered by secondary active transport is logically related to the proton pump.arrow_forwarddrawing chemical structure of ATP. please draw in and label whats asked. Thank you.arrow_forward
- Outline the negative feedback loop that allows us to maintain a healthy water concentration in our blood. You may use diagram if you wisharrow_forwardGive examples of fat soluble and non-fat soluble hormonesarrow_forwardJust click view full document and register so you can see the whole document. how do i access this. following from the previous question; https://www.bartleby.com/questions-and-answers/hi-hi-with-this-unit-assessment-psy4406-tp4-report-assessment-material-case-stydu-ms-alecia-moore.-o/5e09906a-5101-4297-a8f7-49449b0bb5a7. on Google this image comes up and i have signed/ payed for the service and unable to access the full document. are you able to copy and past to this response. please see the screenshot from google page. unfortunality its not allowing me attch the image can you please show me the mathmetic calculation/ workout for the reult sectionarrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher: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 CollegeUnderstanding Nutrition (MindTap Course List)Health & NutritionISBN:9781337392693Author:Eleanor Noss Whitney, Sharon Rady RolfesPublisher:Cengage Learning
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning




