Genetics Review: X-linked traits, pedigrees, breeding, dihybrid crosses, linkage, and probability

A set of fill-in-the-blank flashcards covering X-linked inheritance, pedigrees, pure lines, monohybrid and dihybrid crosses, Punnett squares, gene linkage, and basic probability calculations in genetics.

A sex-linked (X-linked) trait is carried on the __ chromosome.

X chromosome

X-linked traits are often expressed in __, and can appear to skip generations in a family pedigree.

males

If a trait is determined by a single event like a coin flip, the probability of getting heads twice in a row is __.

1/4

A cross examines one trait, while a cross examines two traits.

monohybrid; dihybrid

Selfing true-breeding plants yields offspring that are all __ for the trait.

homozygous

In a true-breeding cross, the offspring are all homozygous for the trait, either or .

homozygous dominant; homozygous recessive

To analyze a two-trait cross, you typically use a __ square.

Punnett

In a dihybrid cross of true-breeding parents for two traits, the expected phenotypic ratio in the F2 generation is __.

9:3:3:1

If two genes are on the same chromosome and do not assort independently, they are said to be __.

linked

The presence of recombinants in a cross is evidence for genetic __ between genes.

linkage

To have at least a 95% chance of finding at least one individual with a recessive trait in a sample, you use the formula P = __.

1 − (1 − p)^n

The probability of getting at least one occurrence in n trials is often solved using __ when p is small.

logarithms

F1 is the abbreviation for the first filial generation, and F2 is the __ generation.

second filial

Punnett squares show how the gametes from the F1 generation combine to predict the __ generation.

F2

In the dihybrid ratio 9:3:3:1, the four phenotypes correspond to two dominant traits and two recessive traits at each locus, with the pattern of __.

independent assortment

A dihybrid cross involving true-breeding parents for two traits yields offspring with two-trait phenotypes in the ratio __.

9:3:3:1