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In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male that is heterozygous for the lethal allele and a normal female? A)  B)  C)  D) 

Using pea plants where the purple color flower is dominant and the white color flower is recessive, a pea plant has 2 different alleles for flower color.  This organism is said to be _____ for the gene that controls flower color.

The individual with genotype AaBbCCDdEE can make many kinds of gametes. Which of the following correctly describes why this situation is possible? 

A star which is 20 times as massive as our Sun is more likely to undergo

A star like our Sun  remains on the main sequence for

Most of sunspots appear

One of the Ca spectral lines coming from a distant star is red-shifted by 20 nm. This line of Ca when emitted from a stationary source in our lab it is found at 500 nm.

Sun’s energy is mainly

The Hertzsprung-Russell (H-R) diagram is

1.1.6 Social costs consist of the sum of private and …. costs. (2)