Blood vessels are muscular tubes that carry blood, sugar, and oxygen to the parts of the body. Nervous impulses cause these tubes to expand or contract. Which system do the vessels belong to? Group of answer choices

circulatory

nervous

digestive

muscular

How can you keep track of variables in a science experiment?

Plz genetic engineering can be applied to many fields including medicine and agriculture. which of the following is a medical application of genetic engineering? a. giving crop plants recombinant dna so that they would be resistant to herbicides. b. examining a persons pedigree to determine whether they can carry a gene for a genetic disease. c. analyzing a persons dna to see how closely they are related to another person. d. certain genes into bacteria so that they will produce a needed medicine.

Were you able to observe the nucleolus in any of the cells if so which ones