Answer:
sarcomeres
Explanation: A contracting skeletal muscle fiber typically shortens as all of its sarcomeres do this.... Thick and thin protein filaments in sarcomeres interact to cause.... True or false, thick and thin filaments maintain their same length whether the muscle is relaxed or contracted?
Answer:
The most diverse group of seedless vascular plants are <u>the ferns .</u>
Explanation:
Ferns -
Ferns are the most advance seedless vascular plants and is the most diverse group . Ferns have branching roots and large leaves . But the whisk ferns , have lack of roots and leaves due to evolutionary reduction . In the process of evolutionary reduction , the natural selection reduces the size of the structure which no longer favors the particular environment . Hence , Photosynthesis in whisk ferns takes place in their green stem .
Answer:
1.The pleural cavity aids optimal functioning of the lugs during breathing. It transmits movements of the chest wall to the lungs, particularly during heavy breathing. The closely approved chest wall transmits pressures to the visceral pleural surface and hence to the lung (10-19.
2.The diaphragm, located below the lungs, is the major muscle of respiration. It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily. Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarge.
Explanation:
Answer:
<h3><em>Both DNA, which stores genetic information and encodes protein sequences, and RNA, which is involved in the direct production of proteins, are nucleic acids.</em></h3>
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Explanation:
Answer:
In eukaryotic cells you find core and proximal promoters.
Promotors are specific DNA sequences where transcription factors (proteins) and RNA polymerase binds to initiate transcription. Promotors are located upstream the coding sequence
Core promoters are where RNA polymersae binds and proximal promoters are where transcription factors bind.
Enhancer elements are DNA sequences where transcription factors (proteins) bind to increase the rate of expresion of an specific gene. Enhancers can be located either upstream, downstream or thousands of nucleotids away from the of the coding region.
Explanation:
Promoters and enhancer are key elements for controling gene regulation. Transcription begins when chromatin rearranges from a condensed state to a accesible state, this allow to transcrition factors and RNA polymerase to bind specif DNA sequences (promotors). Proteins bind to enhancers , this complex develops a DNA loop, so that the protein that is bound to the enhancer interacts with the RNA polymersase. When this interaction is made, the activity of the RNA polymerase is increased.