What roles do membrane proteins play in making the cell membrane selectively permeable

Which statement best explains how cellular respiration maintain homeostasis in animals? it maintains body temperature by absorbing energy. it breaks glucose into energy required by the organism. it speeds up metabolism by making oxygen. it produces energy from hormones present in the organism.

The trp operon in e.coli regulates genes that code for enzymes required for synthesis of the repressible operon. when tryptophan is not available amino acid tryptophan. the trp operon is a in the environment, the trp repressor protein activeinactiveregulated. therefore, rna polymerase can bind to the genes to begin transcription.

Witch type of microscope is used to view very small cell components like proteins and dna?