If a population's allele and genotype frequencies remain...

Name: Problem 4, Chapter 19: Biology
Uploaded: 2021-07-08T03:44:06-08:00
Duration: 7 min 11 s
Channel: Mathew Botros
Description: If a population's allele and genotype frequencies remain constant from generation to generation, (a) the population is undergoing evolutionary change (b) the population is said to be at genetic equilibrium (c) microevolution has taken place (d) directional selection is occurring, but only for a few generations (e) genetic drift is a significant evolutionary force

If a population's allele and genotype frequencies remain constant from generation to generation, (a) the population is undergoing evolutionary change (b) the population is said to be at genetic equilibrium (c) microevolution has taken place (d) directional selection is occurring, but only for a few generations (e) genetic drift is a significant evolutionary force

Key Concepts

Genotype Frequencies

Genotype frequency refers to the proportion of different genotypes within a population. When a population is at genetic equilibrium, the distribution of these genotypes remains unchanged from generation to generation. This consistency is a crucial indicator that the underlying allele frequencies are not being altered by factors like selection or mutation.

Allele Frequencies

Allele frequency is a measure of how common a specific allele is in a population. It is defined by the proportion of all alleles at a given locus that are of a specified type. In populations at genetic equilibrium, allele frequencies remain constant across generations, indicating the absence of evolutionary forces acting on that gene.

Hardy-Weinberg Principle

The Hardy-Weinberg Principle is a fundamental concept in population genetics. It establishes a mathematical model that describes how allele and genotype frequencies in a population remain constant from one generation to the next, provided that certain key conditions are met. This principle serves as a null hypothesis for detecting when evolutionary forces, such as natural selection, mutation, gene flow, or genetic drift, are at work.

Genetic Equilibrium

Genetic equilibrium refers to the state in which a population's allele and genotype frequencies remain constant over time. This situation implies that no evolutionary forces or changes in mating patterns are significantly influencing the genetic makeup of the population, and the population is essentially in a balance as predicted by the Hardy-Weinberg Principle.

Transcript

00:07 So today's video is on the population's alleles and frequency that has remained constant over generation and to another generation.

00:27 Since the question has answers that are multiple choice, we're going to go over like what the multiple choice answers based on vocabulary instead of like me showing you the multiple.

00:42 Choice and then i just pick an answer as you like in previous videos the reasoning is i figured like it's better to just go over the words the vocab that we use in the multiple choice rather than just you know show it on screen and then trying to figure it out from there but we'll see as we go along so our keyword in the question is constant so the question basically said the populations, alleles, and frequency was constant.

01:24 If you know what constant means, it just stays the same.

01:30 And a few of the answer choices, which we're going to go over, was evolutionary change.

01:38 We're going to go by vocab.

01:39 So evolutionary change.

01:43 That was option a.

01:45 That's the one that said evolutionary change is occurring.

01:50 Genetic equilibrium, microevolution, and directional selection.

02:36 Last one, genetic drift.

02:38 We're going to go over all of them.

02:42 And the best way to do this is just basically know that our keyword is constant within the question.

02:49 So the first one said evolutionary change...