In 1907, a horse named clever hans was said to be able to answer math problems posed to him. he would tap out the correct answers with his hoof. however, an investigation revealed that if clever hans could not see the person asking the question, he did not provide correct answers. what does this suggest?
a : this illustrates the importance of including control groups -- without a second horse, no conclusion can be drawn.
b : clever hans was responding to subtle visual cues from the questioner.
c : clever hans was motivated to answer correctly by social interaction.
d : all of the choices are correct.

Coat color in cats is determined by genes at several different loci. at one locus on the x chromosome, one allele (x ) encodes black fur and another allele (xo) encodes orange fur. females can be black (x x ), orange (xoxo), or a mixture of orange and black called tortoiseshell (x xo). males are either black (x y) or orange (xoy). bill has a female tortoiseshell cat named patches. one night, patches escapes from bill\'s house, spends the night out, and mates with a stray male. patches later gives birth to the following kittens: one orange male, one black male, two tortoiseshell females, and one orange female. what are the genotypes of patches, the stray male, and the kittens?

Pink fur (p) is dominant to purple fur (p) in hamsters. two heterozygous pink hamsters are crossed. what is the probability that these two parents will have an offspring with purple fur? 2/4, 1/2 or 50% 1/4 or 25% 3/4 or 75% 4/4 or 100% there is no chance for this type of offspring

Physical characteristics of down syndrome