Which of the these combinations result in the expression of a recessive trait? a. two dominant alleles
b. A Y chromosome
c. two recessive alleles
d. a dominant allele and a recessive allele

Consider darwin's first writings on the theory of natural selection. an important point of darwin's essay on the principle of population, written in 1798, was a peer's observation that in nature plants and animals produce far more offspring than can survive, this observation can be attributed to a) charles lyell. b) thomas malthus. c) jean-baptiste lamarck. d) johann friedrich meckel.

You are observing different types of cells in your science lab. one cell has many chloroplasts. what is the most likely function of this cell? a. energy production b. photosynthesis c. reproduction d. digestion

What part of the cell does 9 represent? a. cytoplasm b. lysosome c. ribosome d. centrosome