Please help me I really studied hard I just don't understand this.

Which of the following is a cause of a dna mutation? o a. the linking of amino acid subunits into a long chain o b. the transcription of dna into rna o c. an error in the repair of damaged dna d. the diffusion of molecules across the cell membrane submit

An organ system consists of a group of organs that performs specific functions necessary for the survival of an organism. humans have eleven different organ systems: integumentary, skeletal, muscular, nervous, endocrine, circulatory, lymphatic, respiratory, digestive, urinary, and reproductive. discuss the function of neurons, the brain and the spinal cord within the human nervous system while explaining the interrelationship of each organ.

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell