Heredity

Topics in this chapter

• Genes, DNA, and Chromosomes
• Mendelian Inheritance and Crosses
• Variation and Inherited Traits
• Human Sex Determination
• Evolutionary Evidence and Adaptation
• Natural Selection and Speciation

Cheat sheet

Practice questions

1. Question 1Q-2EA0CA

   A cross between a tall pea plant (TT) and a short pea plant (tt) resulted in progeny that were all tall plants. What does this observation indicate?

   1. A.Tallness is a recessive trait and shortness is dominant.
   2. B.Tallness is a dominant trait and shortness is recessive.
   3. C.Both tallness and shortness are codominant traits.
   4. D.Height is not an inherited trait in pea plants.
   See the answer and solution
2. Question 2Q-C35634

   Which of the following constitutes the hereditary material in most living organisms?

   1. A.Protein
   2. B.Carbohydrate
   3. C.DNA
   4. D.Lipid
   See the answer and solution
3. Question 3Q-A151BE

   In humans, the biological mechanism of sex determination depends upon:

   1. A.The sex chromosome contributed by the mother's egg cell.
   2. B.The environmental temperature during embryonic development.
   3. C.The sex chromosome contributed by the father's sperm cell.
   4. D.The total number of autosomes present in the zygote.
   See the answer and solution
4. Question 4Q-DAE6DA

   A pure breeding tall pea plant with round seeds (TTRR) is crossed with a pure breeding dwarf plant with wrinkled seeds (ttrr). What proportion of the $F_2$ generation plants will exhibit the new combinations of traits (tall with wrinkled seeds, or dwarf with round seeds) according to Mendel's dihybrid cross?

   1. A.1/16
   2. B.3/16
   3. C.6/16
   4. D.9/16
   See the answer and solution
5. Question 5Q-774E74

   Which of the following statements accurately distinguishes between inherited traits and acquired traits?

   1. A.Inherited traits are developed during a lifetime, while acquired traits are passed from parents to offspring.
   2. B.Inherited traits involve changes in DNA germ cells, whereas acquired traits involve changes in non-reproductive body tissues.
   3. C.Acquired traits can be directly inherited by the next generation, unlike inherited traits.
   4. D.Both inherited and acquired traits are equally capable of being passed on to progeny.
   See the answer and solution