What important molecule is housed in the nucleus and directs the day to day activities of a cell? proteins dna lipids

Consider the skeleton. which skeletal system is represented by the shaded portion of the skeleton? spongy skeleton compact skeleton axial skeleton appendicular skeleton

Which cell organelle is the site for photosynthesis? a. chloroplast b. endoplasmic reticulum c. golgi apparatus d. lysosome

According to the rna world hypothesis, rna acted as the genetic material and catalyzed reactions in ancient cells. what conclusion can you draw from this?               a.  this implies that dna and proteins aren't essential in cells today.    b.  this implies that rna can catalyze any chemical reaction that enzymes catalyze.    c.  this implies that if a cell has a problem with its dna, its rna can compensate for the damaged dna.    d.  this implies that dna and proteins evolved after rna.