Food moves through the digestive system tract by peristalsis, which is produced by wavelike contractions of INVOLUNTARY muscles
Answer:
Both Bacteria and Archaea are prokaryotes, single-celled microorganisms with no nuclei, and Eukarya includes us and all other animals, plants, fungi, and single-celled protists – all organisms whose cells have nuclei to enclose their DNA apart from the rest of the cell.
Explanation:
Both Bacteria and Archaea are prokaryotes, single-celled microorganisms with no nuclei, and Eukarya includes us and all other animals, plants, fungi, and single-celled protists – all organisms whose cells have nuclei to enclose their DNA apart from the rest of the cell.
Answer:
Depending on the stimulus, graded potentials can be depolarizing or hyperpolarizing. Action potentials always lead to depolarization of membrane and reversal of the membrane potential. Amplitude is proportional to the strength of the stimulus. ... Duration of graded potentials may be a few milliseconds to seconds.
Explanation:
Answer:
No, mutations do not all result in negative effects. Sometimes they can be beneficial, as they are completely random. It is our general tendency to think of the word "mutation" in negative terms; however, do not get confused. Mutations are the root/ultimate source of genetic variation; they are one of the main factors that allow populations to evolve.
Answer: Promoter
Explanation:
Transcription is the first step in gene expression which consists of copying the DNA sequence of a gene to produce a RNA molecule. There are enzymes called <u>RNA polymerases which perform this process of transcription</u>. These enzymes bind nucleotides (the monomers which are part of the nucleic acids) to create a RNA strand using a DNA strand as a mold.
A promoter is a region of DNA that controls the initiation of transcription of a given portion of DNA to RNA. Therefore they promote the transcription of a gene. <u>The promoter region is composed of a specific sequence of DNA located just where the starting point of the DNA transcription is</u> and contains the information needed to activate or deactivate the gene it regulates. <u>The promoter has a binding site for the RNA polymerase enzyme </u>in charge of mRNA synthesis and when it recognizes this site, transcription begins.