Which of the following scenarios refutes the argument that genes are entirely internally influenced? a. patrick possesses a gene for brown hair, but his children have blond hair. b. cindy possesses a gene for freckles, but she uses makeup to cover them up. c. margaret possesses a gene for melanoma, so she chooses to stay out of the sun. d. charles possesses a gene for alzheimer's, but he has not yet experienced symptoms.

The actual answer is C.

Explanation:

From Odyssey: "There are internal and external environmental influences regarding if and how genes are expressed. For an internal example, have you ever noticed that most male birds are more brightly colored than female birds? This is because chemicals only in the males control whether the gene for bright colors is expressed. An example of an external influence is a person who stays out of the sun because they know that they are at risk for developing a deadly type of skin cancer, and their behavior may keep them from getting the cancer."

i it is d i hope it

fertilization, pictured in figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. the egg and sperm each contain one set of chromosomes. to ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. in mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. when a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. in placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in figure 24.23b. the fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. the nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.

explanation: