Answer:
Clam.
Explanation:
Arthrophoda is largest phylum of the non-chordata. They are the segmented animals with jointed appendages. Their body is covered by exoskeleton and contains spiracles and body surface for respiration.
Insect, spider, crab and scorpion all are included in the phylum arthropoda. Clam is a bivalve shell that is included in the phylum mollusc. The body of clam is covered with an outer shell and their shells are connected by the abductor muscle. Hence, they are involved in phylum arthropoda.
Thus, the correct answer is option (b).
Select the two terms that correctly complete this statement. Observable traits exhibited by an organism do not always indicate the exact genetic makeup of
that organism because of recessive alleles and <span>polygenic traits</span>.
Answer:
Change in chromatin structure-------Acetylation of histones facilitates transcription
Activity of transcription apparatus------Transcriptional activators increase promoter activity by interacting with the RNAPII holoenzyme
RNA processing---------Alternative splicing produces different transcripts from the same gene.
RNA interference-------A siRNA and the transcript it targets is transcribed from the same gene.
Initiation of translation-------Limited availability of initiation factors prevents translation of mRNA.
Answer:
Nervous stimulus action for muscle contraction
Explanation:
Nerve stimulation is sent to the sarcolemma, which are motor nerves at the neuromuscular junction (junction between the terminal part of a motor axon with a motor plate), after which nerve endings implant in the sarcolemma and form plaque on the surface of muscle fibers, which in turn transmit stimulus to the musculature.
Then, an electrical current (from the stimuli) is generated, it propagates through the muscle cell membrane, reaches the cytoplasm and triggers the muscle contraction mechanism.
Boys shoulders broaden and voice deepen, Girls start having menstrual periods and develop breast. <span />