Chapter 10

How are the predicted results of crosses different with sex-linked genes?

that each fertilization event has a 50% chance of producing a female and a 50% chance of producing a male. Traits are located on sex chromosomes ( X or Y ), causing inheritance patterns to depend on the sex of the parent and offspring.

Sex-Biased Expression: X-linked recessive traits are far more common in males because they only have one X chromosome, meaning they cannot be masked by a dominant allele.

Criss-Cross Inheritance: Typically, mothers pass X-linked traits to sons, and fathers pass X-linked traits to daughters

Who was Gregor Mendel? What did he do? 

an Austrian monk and scientist known as the "father of modern genetics"

• Was the first person to analyze patterns of inheritance (using math)

• Figured out some of the fundamental principles of genetics (predicted meiosis before it was discovered)

What is a monohybrid cross?

a cross between parent plants that differ in only one single trait

What does heterozygous mean?

having two different versions (alleles) of a specific gene, one inherited from each parent

Ex: Bb or bB

What is an allele?

a variant form or "version" of a specific gene

recessive trait

a genetic characteristic that appears in a phenotype only when an organism inherits two identical recessive alleles (one from each parent)

phenotype

the set of observable characteristics, traits, or behaviors of an organism, resulting from the interaction of its genotype (genetic makeup) with the environment. Examples include hair color, blood type, height, and disease presence.

genotype

the specific genetic makeup or set of alleles (variants) an organism inherits from its parents, typically represented by symbols like Aa, AA , aa

Dominant

a genetic variant that expresses its associated trait or phenotype in an organism even when only one copy is present

Homozygous

Having inherited two identical versions (alleles) of a specific gene, one from each biological parent.

Ex: bb or BB