Biology Chapter 4 Review Flashcards

Questions and Answers

How did Mendel study heredity?

Mendel bred pea plants and studied the characteristics of different generations.

How do you know which traits are dominant in an organism like a pea plant?

The traits that are expressed in the first generation of offspring of a cross of two different purebreds are dominant.

What is a dominant trait?

A trait of a specific character that appears in a hybrid organism.

What are the three principles of heredity?

<ol> <li>In a cross of purebreds, all offspring will show the dominant trait. 2) For any one character, the two alleles for a parent's gene separate and then combine with the other parent's alleles to determine the offspring's trait. 3) A parent passes each allele to its offspring independently of all other alleles.</li> </ol> Signup and view all the answers

How do genotypes and phenotypes relate?

A genotype is the genetic information that produces a phenotype, or physical trait. Signup and view all the answers

A pea plant with yellow pods has a genotype of gg. Is it purebred or a hybrid? Is the yellow pod trait dominant or recessive?

Purebred, recessive Signup and view all the answers

A purebred pea plant with green pods (PP) has been crossed with a purebred pea plant with yellow pods (pp). What is the genotype and phenotype of the first generation offspring?

Genotype Pp, phenotype green pods. Signup and view all the answers

What is the probability?

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Study Notes

Mendel's Study of Heredity

Gregor Mendel investigated heredity through breeding experiments with pea plants, analyzing traits across generations.

Dominant Traits in Pea Plants

Dominant traits emerge in the first generation when two different purebred plants are crossed and are commonly expressed in hybrid offspring.

Definition of Dominant Trait

A dominant trait is one that appears in a hybrid organism, overriding the expression of recessive traits.

Principles of Heredity

Offspring from purebred crosses exhibit only the dominant trait.
During reproduction, alleles from each parent separate and recombine, influencing offspring traits.
Alleles are passed independently from one another, allowing for diverse trait combinations.

Relationship Between Genotypes and Phenotypes

Genotype refers to the genetic makeup of an organism, while phenotype describes the observable traits that result from the genotype.

Characteristics of a Genotype gg

A pea plant with a genotype of gg is categorized as purebred and features a recessive trait, in this case, yellow pods.

Offspring of Green and Yellow Pod Cross

Crossing a purebred green pod plant (PP) with a purebred yellow pod plant (pp) results in offspring with a genotype of Pp and a phenotype displaying green pods.

Understanding Probability in Genetics

Probability in genetics refers to the likelihood of certain traits manifesting in the offspring based on parental genotypes.

Description

This quiz covers key concepts from Chapter 4 of your biology curriculum, focusing on Mendel's studies of heredity through pea plants. Review important definitions and understand dominant traits in offspring. Perfect for exam preparation and reinforcing your understanding of genetic inheritance.