The four tissue types that have intercellular junctions are;epithelial tissue, connective tissue, muscle tissue andnervous tissue.
Answer:
E
Explanation:
E is the right answer that you're looking for ;)
Answer:
Okay
Explanation:
Human topoisomerase I plays an important role in removing positive DNA supercoils that accumulate ahead of replication forks. It also is the target for camptothecin-based anticancer drugs that act by increasing levels of topoisomerase I-mediated DNA scission. Evidence suggests that cleavage events most likely to generate permanent genomic damage are those that occur ahead of DNA tracking systems. Therefore, it is important to characterize the ability of topoisomerase I to cleave positively supercoiled DNA. Results confirm that the human enzyme maintains higher levels of cleavage with positively as opposed to negatively supercoiled substrates in the absence or presence of anticancer drugs. Enhanced drug efficacy on positively supercoiled DNA is due primarily to an increase in baseline levels of cleavage. Sites of topoisomerase I-mediated DNA cleavage do not appear to be affected by supercoil geometry. However, rates of ligation are slower with positively supercoiled substrates. Finally, intercalators enhance topoisomerase I-mediated cleavage of negatively supercoiled substrates but not positively supercoiled or linear DNA. We suggest that these compounds act by altering the perceived topological state of the double helix, making underwound DNA appear to be overwound to the enzyme, and propose that these compounds be referred to as ‘topological poisons of topoisomerase I’
Answer:
The most correct answer is: It varies in consistency based on the amount of protein fibers and fluid
Explanation:
The extracellular matrix (ECM) is the environment surrounding cells, which is normally composed by fibers (i. e.: collagen, elastin, etc...), soluble proteins and other macromolecules (such as hyaluronic acid) embedded in fluid. The relative concentration and composition of those components conditions, among other things, the physical consistency of the ECM.
- No blood vessel arises from ECM; they derive from specific precursor cells. Additionally, cartilage is an avascular (has no blood vessel) type of connective tissue.
- ECM does provide oxygen and nutrients to diverse tissue, including bone, however bone tissue <em>does</em> have blood vessels.
- Neuronogenesis (generation of new neurons) takes place within the developing nervous system, with neuronal precursor cells being thoroughly surrounded by other cells such as radial glia. Typically, neighboring ECM has a minor or negligible role in this process.
