The bald eagle and the black bear are tetrapods, which means that they both have four limbs along with the digits. This shows that they both are the descendants of the four-limbed ancestors. However, the limbs of the bear and the bald eagle have different functions. The forelimbs of both these organisms serves different purpose. Hence, their limbs are homologous organs. The homologous organs are those which have the same ancestry but the functions are different.
15. B.
16. G. schlerenchyma cells
17. D. ATP
Answer:
a. the coordinated control of gene expression in bacteria
Explanation:
An operon in bacteria is a collection/cluster of genes that are under the control of a single promoter. It includes 3 components: a promoter, the genes and an operator. The operator is where a repressor binds, and the promoter is where transcription begins.
Operons allow organisms to control the expression of multiple genes in response to environmental cues
Answer:
The mRNA leaves the nucleus and travels to the ribosome where proteins are synthesized
Explanation:
During transcription, a messenger RNA (mRNA) molecule is synthesized from a specific DNA region which is referred to as a gene. Subsequently, the mRNA leaves the cell nucleus through the nuclear pores of the nuclear membrane and travels to the ribosome, where this sequence serves as template to synthesize a protein, in a process known as translation. Within the ribosomes, triplets of consecutive RNA nucleotides called codons bind to complementary RNA nucleotides (called anticodons) of the transfer ribonucleic acids (tRNAs). Each tRNA attaches a specific amino acid that corresponds to its anticodon sequence, which is then added to the nascent polypeptide chain.