Match each type of association with the best example commensalism mutualism parasitism amensalism A. A mold produces a chemical that kills bacteria without apparently benefiting B. "Aerobic bacteria in the human colon consume oxygen, making it possible for anaerobic species to survive" C. "Flagellates live in the gut of termites, feeding on the wood consumed by the termite and allowing the termite access to nutrition and energy in wood that they could not otherwise digest" D. "A helminth takes up residence in a human digestive tract, consuming nutrients"

A. A mold produces a chemical that kills bacteria without apparently benefiting.  - amensalism

B. Aerobic bacteria in the human colon consume oxygen, making it possible for anaerobic species to survive.  - commensalism

C. "Flagellates live in the gut of termites, feeding on the wood consumed by the termite and allowing the termite access to nutrition and energy in wood that they could not otherwise digest" - mutualism

D. "A helminth takes up residence in a human digestive tract, consuming nutrients" - parasitism

Explanation:

Amensalism is any relationship between organisms of different species in which one organism is inhibited or destroyed while the other organism remains unaffected.

Two examples of antibiosis amensalism are provided by the bread mold Penicillium and black walnut trees.

Amensalism is the association between organisms of two different species in which one is inhibited or destroyed and the other is unaffected.

Commensalism is a long-term biological interaction in which members of one species gain benefits while those of the other species neither benefit nor are harmed.

Mutualism describes the ecological interaction between two or more species where each species has a net benefit. Mutualism is a common type of ecological interaction.

parasitism is a symbiotic relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it some harm, and is adapted structurally to this way of life

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.