Bio 101 Chapter 14 Exam 3

Heredity

Heredity

The transmission of traits form parents to offspring

Trait

Any characteristic of an individual

What made the garden pea an ideal organism for Mendel’s study of genes?

1. inexpensive and easy to grow

2. short generation time

3. produce large number of seeds

4. can control which parents were involved mating

What are self and cross fertilization?

Self-fertilization is asexual reproduction while cross-fertilization is when the sperm from one flower used to fertilize another.

What is the difference between genotype and phenotype?

genotype is the set of alleles at a gene while phenotype is the physical output of the genotype.

What is a true-breeding line?

A true breeding line will produce identical offspring to themselves when self-fertilized.

What are hybrids?

The offspring of two different pure breeding lines that differed in one or more traits.

What are homozygous and heterozygous genotypes?

homozygous= two of the same alleles (RR or rr)

Heterozygous= two different alleles (Rr)

Autosomal Inheritance

The patterns of inheritance of any genes not on a sex chromosome. These are the “standard” patterns of inheritance.

Reciprocal Cross

A cross in which the phenotypes of the male and female are reversed compared with a prior cross.

Testcross

A cross of a homozygous recessive individual and an individual with the dominant phenotype but unknown genotype.

X-Linked

Referring to a gene located on the X chromosome.

Y-linked

Referring to a gene located on the Y chromosome.

What is the meaning of the P, F1, F2, etc. generations?

P= Parental Generation

F1= Offspring of P

F2= Offspring of F1

What is a back cross?

Backcrossing is a crossing of a hybrid with one of its parents.

In general, why do sex-linked disorders manifest differently than autosomal disorders?

sex-linked disorders manifest differently because some disorders are specifically x-linked or y-linked which means based on your gender you are more or less likely to get a specific disorder.

Incomplete dominance

Alleles are not always dominant or recessive, heterozygote has an intermediate phenotype.

codominance

Simultaneous expression of phenotype associate with each of the alleles in heterozygote. AB blood type.

pleiotropy

1 gene affects many traits. Example Marfan syndrome

epistasis

Two or more genes effect 1 trait.

quantitative traits.

Traits that vary continuously. Can be plotted on a bell shaped curve. Ex= height or weight

Understand how to recognize male/female diseased/carrier/non-disease individuals in a pedigree.

Male= square

Female= circle

Diseased= filled in

Carrier= half filled

non-disease=empty

How would an X-linked, Y-linked disorder or autosomal disorder show up in a karyotype?

X- linked and Y-linked would show up in the sex chromosomes while autosomal disorders would show up in the non-sex chromosomes.