bio chp7

While studying the outcomes of reproduction in ____________, Gregor Mendel found that each individual carries ___________ copy/copies of the allele for each trait and that ____________ is/are passed on to each offspring. When studying inheritance of two different traits, Mendel found that the patterns of inheritance of one trait __________ the patterns of inheritance of another trait. This concept is now called _________.

1. pea plants 2. two 3. one 4. has no effect 5. the law of independent assortment

In modern terms, Mendel's law of - states that each gamete formed through - receives a -, while the law of - states that the alleles in those gametes are chosen -.

1. segregation 2. Meiosis 3. single allele of each gene 4. independent assortment 5. at random

In pea plants, the tall allele (T) is dominant to the short allele (t) and the yellow pea allele (Y) is dominant to the green pea allele (y). In a cross between a TTYy pea and a ttyy pea, what are the odds that the offspring will be tall and have green peas?

1/2 or 50%

A recent study found that at least 180 different genes seem to be correlated with height in humans, which is partly why height is a continuous trait. If we imagine a much simpler scenario in which only 10 genes control height, and each of these genes displays simple Mendelian inheritance (i.e., there are only two alleles, tall and short, and tall is dominant to short) and shows equal contribution to height, how many different possible genetic height phenotypes would there be in humans?

11

The human ABO blood type trait displays four phenotypes: A, B, AB, and O. It is controlled by a single gene which has three possible alleles: A, B, and O. The A and B alleles are codominant, and the O allele is recessive to both A and B. How many different possible genotypes exist for this gene?

6

If two chickens with the genotypes Aarr and AARR are crossed, what are the possible genotypes of their offspring

AaRr, AARr

If both a father and a mother have a good sense of humor, they should expect a maximum of 25% chance that they would have an offspring without a good sense of humor.

False

When a gene possesses both dominant and recessive alleles, there are usually more possible phenotypes than genotypes.

False

When geneticists first studied eye color, it was suggested that the "blue-eyed" trait was caused by a single recessive allele. Further study indicated that, while rare, blue-eyed parents could have a brown-eyed child. Which of the following statements best describes this trait and the reason for its occurrence?

It is a complex trait because the rules of dominance are not followed

Two pea plants are crossed to make 1,000 offspring. All offspring possess long pods and round peas. Long pods (L) are dominant to short pods (l), and round peas are dominant (R) to wrinkled peas (r). Which of the following are possible genotypes of the parent plants?

LLrr x llRR LLRR x llrr

Your pet cat, Ms. Pickles, is heterozygous for short hair length, Ll, and white hair, Ww. What combinations of hair length and hair color alleles can she produce in a single egg?

LW Lw lW lw

Occasionally, a gamete is formed that contains both alleles of a gene instead of one. The result is the presence of three alleles of a gene after fertilization. Which of Mendel's laws would this gamete violate, and when during meiosis would the gamete form?

Law of segregation, meiosis I

Two cats are both heterozygous for hair length, Ll, and heterozygous for white hair, Ww. Short hair and white hair are dominant to long hair and colored hair, respectively. What are the odds that the pair's offspring would show the following phenotypes?

Long Colored hair = 1/16 Short colored hair = 3/16 Long white hair = 3/16 short white hair = 9/16

Which of the following traits are Mendelian and which show more complex patterns of inheritance?

Mendelian = yellow versus green pea color in pea plants complex = intelligence in humans, coat color in Labrador dogs , body size in human

A female fern plant is heterozygous for a gene related to photosynthesis (Pp). Select all of the different possible genotypes that her eggs could possess

P, p

Gregor Mendel described several traits in pea plants in which a dominant trait masked a recessive trait. Two such traits were plant height (T = tall, t = short) and seed shape (R = round, r = wrinkled). Match each genotype below with its expected phenotype.

Short and Wrinkled = ttrr Tall and Round = TTRR, TtRr, TTRr Tall and wrinkled = TTrr, Ttrr Short and round =

In humans, ear wax might be controlled by a single gene showing Mendelian inheritance, where the two phenotypes are wet ear wax and dry ear wax, and the wet ear wax trait is dominant to the dry ear wax trait. Interested in understanding this trait, you study families and compile the following data.

Since no pairs of parents with dry ear wax produced an offspring with wet ear wax, this trait is likely to be governed by a single gene

A single gene trait with two alleles that show incomplete dominance should possess the same number of possible genotypes and phenotypes.

True

A brown mouse is repeatedly crossed with a white mouse and produces 43 offspring, all of which are brown. Assuming that mouse hair color is a Mendelian trait (dominant allele = B), drag the correct genotype to each parent mouse.

White mouse = bb Brown mouse = BB

In Labrador dogs, coat color is controlled by the genotypes of two genes. In one gene, the dominant allele, B, produces black fur, and the recessive allele, b, produces brown fur. However, if a second gene possesses two recessive alleles, ee, the dog produces yellow fur, regardless of the genotype of the first gene. If two dogs that are heterozygous for both genes, BbEe mated, what would be the frequency of the three phenotypes, black, brown, and yellow?

brown = 3/16 black = 9/16 yellow = 4/16

Most traits in humans display Mendelian inheritance

false

Two blue-eyed parents can produce a brown-eyed offspring. Blue eyes are recessive

false

The fur color of Siamese cats is partly controlled by temperature. Where their skin is relatively cool, like their ears, their fur grows dark, and where their skin is warmer, like their torso, their fur grows white. In this example, temperature is affecting what aspect of the Siamese cat?

phenotype

In 4 o'clock flowers, flower color is controlled by a single gene with two alleles. The R allele produces red flower color, and the W allele produces white flower color. These alleles display incomplete dominance, and when both alleles are present, the flowers appear pink. Remember, when dealing with incomplete dominance, only capitals are used for the two traits because neither allele exerts dominance over the other. Match each of the following genotypes to the correct color of flowers.

red flowers = RR, Homozygous pink flowers = RW, WR, Heterozygus white flowers = WW, Homozygous