The sex of birds, some insects, and other organisms is determined by a ZW chromosomal arrangement in which the males have like sex chromosomes (ZZ) and females are ZW (similar to XY in humans). Assume that a recessive lethal allele on the Z chromosome

causes death of an embryo in birds. What sex ratio would result in the offspring if a cross were made between a male heterozygous for the lethal allele and a normal female?

A) 4:1 male to female
B) 3:1 male to female
C) 2:1 male to female
D) 1:1 male to female
E) 1:2 male to female


Answer: C

Biology & Microbiology

You might also like to view...

Which of the following enabled Homo sapiens to develop complex cultures unlike other members of the Homo genus?

A. the ability to walk upright B. the development of agriculture C. the ability to migrate out of Africa D. changes in skin color E. the ability to use stone tools

Biology & Microbiology

An endocrine axis describes:

A. a hormonal signaling pathway between endocrine glands and tissues. B. the direction of hormone transport within the body. C. the molecule that forms the backbone of a hormone. D. the signal transduction cascade that occurs when a hormone binds to a receptor. E. the pattern of genes that are expressed in response to a hormone.

Biology & Microbiology

In the life cycle of a fern, what is the name of the structure that produces the haploid spores?

a. sori b. rhizome c. gametophyte d. gametangium e. strobilus

Biology & Microbiology

Second largest category; there are six domains of life: Bacteria, Archaea, Protists, Animals, Plants, Fungus

Biology & Microbiology