If an egg is in one of the fallopian tubes, approximately how many sperm will surround it and try to cross the egg cell's membrane? a. hundreds b. thousands c. millions d. billions

Which symbols below represent the ions found in the glass of water ? a. oh- and h+ b. co2 and o2 c. o2 and h2 d. nh3- and h+

Which statement best describes the relationship between an allele and a gene? question 1 a. an allele is a variation of a gene that can be expressed as a phenotype. b. an allele is the part of a gene that attaches to messenger rna molecules. c. an allele is a segment of a dna molecule that controls replication of a gene.

What sentence best supports the statement that hormones are involved in the regulation of homeostasis? a. the hormone erythropoeitin increases the production of red blood cells when oxygen levels are low. b. the hormone oxytocin promotes labor contractions of the uterus during childbirth. c. the hormone melatonin induces sleep and its production is slowed by exposure to light. d. the hormone cortisol suppresses the immune system and is produced when the body is under stress.