Answer:
b
Explanation:
its in a quizlet created in 2017
Answer:
This statement is true
Explanation:
The genetic code is required for the production of proteins with exception of some few mitochondrial proteins. The transfer RNA (tRNA) acts as an adaptor that enables to associate a messenger RNA trinucleotide sequence (known as anticodon) with its corresponding amino acid in the polypeptididic chain. The genetic code is considered to be a biochemical system capable of revealing the information contained in the DNA in order to synthetize a protein, which has been encrypted in the form of three nucleotides (i.e., codons).
Striated muscles contain repeating sarcomeres of overlapping arrays of long, thin actin and thicker myosin filaments. Myosin filaments contains the myosin heads, which are enzymes that can bind to actin, split and make use of the energy from ATP. When muscle contraction starts, myosin heads bind to actin, change their configuration on actin, liberating the products of ATP hydrolysis and causing slide of the actin and myosin filaments. The action of the proteins troponin and tropomyosin on the actin filaments regulates vertebrae striated muscle contraction. The release of calcium ions from the sarcoplasmic reticulum is triggered by the nervous stimulation which causes depolarization of muscle membrane. Calcium ions bind to troponin and thus cause or allow the tropomyosin strands on the actin filament to move so that the part of the actin surface where myosin heads need to bind is uncovered. Contraction then occurs and only stops when the sarcoplasmic reticulum pumps calcium out of the muscle interior.
So basically, what triggers the uncovering of the myosin binding site on actin is the calcium ions binding to troponin and changing configuration.
I know C they may change shape when they bind substrates
