Azebra cell is just about to replicate its dna. what happens first?
an rna molecule attaches to a dna molecule.
the dna folds over on itself to create a dense chromosome.
enzymes unwind the dna molecule into two strands.
the dna molecule attaches to proteins.

2. if scientists identify an animal with bilateral symmetry and no segmentation, which phylum can it definitely not belong to? a. roundworms b. annelids c. mollusks d. flatworms

What was dr. willem johan kolff’s first step in using the scientific process to invent the hemodialysis machine? he built the machine and tried it with various patients, collecting data about its effectiveness. when a patient’s kidneys failed, he wondered if it would be possible to perform kidney functions with an external machine. he researched and collected data about numerous patients who exhibited symptoms of kidney failure. he drew conclusions from studies of various symptoms of kidney failure, and drew a design for the ideal external blood-processing machine.

Afamily has a y-linked disease that affects the father. what is the chance of a male offspring inheriting the same disease? oa. 100% ob. 50% oc. 25% d. 0%