Name: how alleles shape inherited traits
Uploaded: 2024-08-29T22:13:37.000Z
Duration: 1 min 25 s
Channel: JoVE

K12 Standards

Arizona Science Standards

High School

Life Science

HS+B.L3

HS+B.L3U1.10

Genetic Variation

Genetic variation stems from differences in DNA sequences among individuals, which are essential for species adaptation and evolution.
Genetic variations originate as ovaries produce eggs and testes produce sperm through a process called meiosis.
The ovaries release eggs that can potentially fertilize with sperm as they travel through the fallopian tubes to the uterus.
Each egg and sperm contribute 23 chromosomes, which are sequences of DNA that encode genes.
Alleles are the different versions of these genes which influence specific traits. For example, the gene determining eye color has various alleles, such as those for blue or brown eyes.
Fertilization results in a zygote with 46 chromosomes, combining genetic material from both parents.
Individuals with two identical alleles for a gene are called homozygous, while those with two different alleles are heterozygous.
For example, individuals with two mutated alleles of a globin gene develop a genetic disorder called sickle cell anemia, whereas heterozygous individuals who carry one healthy and one mutated allele do not exhibit severe disease symptoms.

genetic variation

Genetic variation is the diversity in DNA sequences found among individuals of the same species. This diversity is crucial for a species&#39; survival because it helps organisms adapt to environmental changes. Genetic variation begins with fertilization, where an egg and sperm cell merge. Each of these cells carries 23 chromosomes, up to 46 in the fertilized egg. Chromosomes are long DNA strands that contain genes, the basic units of heredity.
Genes exist in different versions called alleles, which can influence various traits, such as hair and eye color, or even the risk of certain diseases. The specific mix of alleles inherited from both parents creates a unique set of genetic instructions, which shape the offspring&#39;s physical appearance and health characteristics, termed the phenotype.
The genotype is an individual&#39;s specific genetic makeup, determined by the alleles received from both parents. This genetic combination affects how traits are expressed. For instance, eye color is influenced by the alleles for eye color each parent contributes. If both parents provide a recessive allele for blue eyes, their child will likely have blue eyes. Conversely, if one allele is for brown eyes and the other for blue, the dominant brown allele usually prevails, resulting in brown eyes for the child.
The terms homozygous and heterozygous describe whether the two alleles for a particular gene are the same or different. Being homozygous means both alleles are identical, while heterozygous means they are different. This distinction can significantly impact an individual&#39;s health. For example, sickle cell anemia is a condition where individuals with two recessive alleles for the hemoglobin gene have the disease. However, those who are heterozygous, carrying one normal and one sickle cell allele, do not show symptoms of the disease but have a protective advantage against malaria, which is beneficial in areas where malaria is common.

Genetic variation stems from differences in DNA sequences among individuals, which are essential for species adaptation and evolution.
Genetic variations ...

Education

JoVE Core

Introduction to Psychology

Unit 1

Biopsychology

KEY TERMS AND CONCEPTS

how alleles shape inherited traits

Genetic variation helps explain why individuals in the same species can look and act differently. It comes from differences in DNA sequences. This diversity matters because it helps a species survive and adapt when the environment changes.

Variation starts at fertilization, when an egg and sperm cell join. Each of these cells carries 23 chromosomes, so the fertilized egg can have up to 46 chromosomes. Chromosomes are long DNA strands that contain genes, which are the basic units of heredity.

Genes can appear in different versions called alleles. These alleles can affect traits such as hair and eye color. They can also influence the risk of certain diseases. The combination of alleles inherited from both parents creates a unique set of genetic instructions. These instructions shape an offspring’s physical appearance and health traits, which are called the phenotype.

An individual’s genotype is the specific genetic makeup they inherit from both parents. Genotype affects how traits are expressed. For example, eye color depends on the alleles each parent contributes. If both parents pass on a recessive allele for blue eyes, the child is likely to have blue eyes. If one allele is for brown eyes and the other is for blue eyes, the dominant brown allele usually leads to brown eyes.

The terms homozygous and heterozygous describe whether the two alleles for a gene are the same or different. Homozygous means both alleles are identical. Heterozygous means the alleles are different. This difference can affect health. People with two recessive alleles for the hemoglobin gene can have sickle cell anemia. People with one normal allele and one sickle cell allele do not show symptoms, but they have a protective advantage against malaria. This advantage is helpful in areas where malaria is common.

How Alleles Shape Inherited Traits

introduction to biological bases of psychology

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Genetic variation helps explain why individuals in the same species can look and act differently. It comes from differences in DNA sequences. This diversity matters because it helps a species survive and adapt when the environment changes. Variation starts at fertilization, when an egg and sperm cell join. Each of these cells carries 23 chromosomes, so the fertilized egg can have up to 46 chromosomes. Chromosomes are long DNA strands that contain genes, which are the basic units of heredity. <br...

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key terms and concepts

Learn how alleles, genotype, and phenotype work together to shape inherited traits, from eye color to sickle cell anemia and malaria protection.

How Alleles Shape Inherited Traits | JoVE K12

JoVE Core Introduction to Psychology offers an engaging learning experience on the fundamental principles of psychology through concise video lessons. Students will explore important topics such as cognitive processes, emotional regulation, and neural mechanisms, establishing a strong foundation in the study of the mind and human behavior. This series provides an accessible and captivating approach to grasp the essential concepts of the discipline.

introduction to psychology

Next Generation Science Standards

heredity-inheritance-and-variation-of-traits

Heredity: Inheritance and Variation of Traits

HS-LS3-2

Florida Department of Education

SC.912.L.15

SC.912.L.15.15

SC.912.L.16

SC.912.L.16.17

new-york-state-science-learning-standards

New York State Science Learning Standards

Inheritance and Variation of Traits

HS-LS3-1.

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Hardy-Weinberg Principle

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Mutation, Gene Flow, and Genetic Drift

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Heritability

Heritability measures the genetic influence on traits or physical characteristics such as height or eye color.
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Natural Selection and Adaptation

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...

Natural Selection and Mating Preferences

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Evolutionary ...

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DNA Packaging

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Organization of Genes

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Karyotyping

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RNA Structure

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RNA Stability

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Types of RNA

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MicroRNAs

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Transcription

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Translation

Lesson: Translation
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Bacterial Transformation

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What is Gene Expression?

Overview
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The Central Dogma

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The central dogma of biology states that information encoded in the DNA is transferred to messenger RNA (mRNA), which then directs the synthesis ...

Transcription Factors

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Construct an explanation for how the structure of DNA and RNA determine the structure of proteins that perform essential life functions.

HS+B.L3U1.11

Mutations

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Genome Size and the Evolution of New Genes

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Evolutionary Relationships through Genome Comparisons

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Genome Copying Errors

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Multi-species Conserved Sequences

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Gene Duplication and Divergence

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Exon Recombination

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Analyze and interpret data on how mutations can lead to increased genetic variation in a population.

HS+B.L3U1.12

How Alleles Shape Inherited Traits

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