Which statement accurately describes the relationship between the brain and addiction?
a. all drugs act on dopamine synapses in the same way.
b. the brain reacts to excessive dopamine levels by increasing the number of dopamine receptors.
c. normal activities produce heightened responses once receptors are reduced.
d. a higher amount of addictive chemicals are needed to get the same high when fewer receptors are present.

Select the correct answer. tay-sachs disease is caused by a mutation in the hexa gene located on chromosome 15. tay-sachs follows an autosomal recessive pattern of inheritance. with the of the diagram, identify which of the offspring will be an unaffected carrier. a diagram showing the genes of parents who are carriers of tay-sachs disease a. a, b, and c b. b and c c. a and d d. a e. d

Abody cell has been growing and at synthesis proteins.in the nucleus of this body cell,dna replication is taking place. and a copy of the cells genetic material is copied.which of the following is the best conclusion you can make about the life cycle of this cell ? a) the cell is ready to undergo mitosis.and a chemical signal will send the cell to prophase b)the cell is undergoing meiosis and will cross over the genetic material next c)the cell is in the s phase of interphase and will move next to the g2 phase d) the cell is in the g2 phase of the interphase and is ready to begin diving

An uncomfortable feeling in the ears when descending in an airplane is caused by changes in air pressure on the: a. inner ear b. middle ear c. eardrum d. hammer/anvil