Name: punnett squares for predicting traits
Uploaded: 2019-03-11T09:21:16.000Z
Duration: 1 min
Channel: JoVE

K12 Standards

Virginia  Standards of Learning

HIgh School

Life Science

LS.10

LS.10.c

Punnett Squares

퍼닛 구획은 개발자의 이름을 딴 단순한 도표로부모의 유전자형을 기반으로유당분해효소결핍증과 같은단일 유전자 특징을 자손들이 유전 받을 가능성을예상할 수 있게 하는 시각적 방법입니다이 예시에서는 열성 동질 접합체를 가진부모 한 쪽의 유전적 기여가두 개의 소문자 L로 표기된 대립 형질로써윗 부분에 적습니다복합적 대립 형질을 가진 이형 접합체는열성을 뜻하는 소문자 L과우성을 뜻하는 대문자 L을 사용하여 왼쪽에 표기 합니다이 열과 행을 조합하여 각 박스 안에 적어 넣음으로써자손이 갖게 될 가능성이 있는 두 가지의 유전형과 표현형을알 수 있습니다이형 접합체가 될 가능성은 50%로유당을 분해할 수 있게 되고열성 동질 접합체를 가지고 유당분해효소 결핍이 될 가능성은 50%가 됩니다

Edwards, A. W. F. "Reginald Crundall Punnett : 1912 년 케임브리지의 유전학 교수 인 Arthur Balfour." Genetics 192, no. 1 (2012 년 9 월 1 일) : 3. [<a href="https://doi.org/10.1534/genetics.112.143552" target="__blank">소스</a>]

리드, 제임스 B., 존 J. 로스. "멘델의 유전자: 완전한 분자 특성화를 향하여." Genetics 189, no. 1 (2011년 9월 1일): 3. [<a href="https://doi.org/10.1534/genetics.111.132118" target="__blank">출처</a>]

퍼넷 사각형

<h4>개요</h4>
 
 퍼넷 사각형(Punnett square)은 두 부모의 유전자형(genotype)으로부터 자손이 물려받을 수 있는 유전자형을 보여줍니다. 형질(trait)의 유전형식(inheritance pattern; 예: 현성(dominant) 또는 잠성(recessive); 주: 우성(dominant) 또는 열성(recessive)이라고 표현할 수 있지만 우성/열성은 현성/잠성으로 개선해야 할 표현입니다.)을 아는 경우, 퍼넷 사각형을 사용하여 표현형(phenotype)을 물려받는 확률을 알아볼 수 있습니다. 퍼넷 사각형은 형질의 유전이 단일 유전자자리(single gene locus)에 따라 결정되고, 형질이 독립적으로 유전되는 경우만 적용할 수 있습니다. 퍼넷 사각형은 더 복잡한 유전형식을 가진 형질의 유전 확률을 예측할 수 없습니다.
 
 <h4>퍼넷 사각형은 하나 이상의 형질을 물려받을 가능성을 보여줍니다</h4>
 
 퍼넷 사각형은 두 부모의 유전자형 간의 교배(cross)를 통해 발생할 수 있는 자손의 유전자형을 표시하는 시각적 표현입니다. 하나 또는 여러 가지 표현형(또는 형질)의 유전을 나타낼 수 있지만, 두 가지 이상의 형질의 유전을 조사하는 데는 다른 도구가 더 적절합니다.
 
 퍼넷 사각형은 표현형이 단일 유전자자리에 기인하고 감수분열(meiosis) 동안 독립적으로 분류된다는 조건 아래, 자손이 특정 유전자형 또는 특정 형질(즉 표현형)을 일으키는 대립유전자(allele) 쌍을 물려받을 가능성을 알아보는 데 사용할 수 있습니다. 즉, 퍼넷 사각형은 한 형질을 물려받을 수 있는 가능성이 다른 형질을 물려받는 확률에 영향을 미치지 않는 경우, 유전 확률을 계산하는 데 유용합니다. 이러한 가정에는 많은 예외가 있지만 (예를 들어 같은 염색체상의 인접한 유전자에 의해 암호화된 형질) 이 수식은 많은 식물과 동물의 형질에 적용됩니다.
 
 <h4>멘델의 실험이 퍼넷 사각형을 만드는 데 영감을 주었습니다</h4>
 
 퍼넷 사각형은 그레고르 멘델(Gregor Mendel)의 획기적인 완두 실험이 유전의 기본 법칙을 밝힌 지 수십 년 후인 1900년대 초반, 레지날드 퍼넷(Reginald Punnett)에 의해 만들어졌습니다. 오늘날 퍼넷 사각형은 멘델의 실험의 기본 원리를 설명하는 데 자주 사용됩니다.
 
 멘델은 완두 콩과 꼬투리의 모양과 색깔, 꽃 색깔과 위치, 그리고 식물의 크기를 포함한 몇 가지 완두 특징(characteristics)의 유전에 대해 연구했습니다. 멘델은 또한 각각의 특징에 대해 유전된 형질들을 조사했습니다. 예를 들어 보라색과 흰색은 꽃 색깔 특징을 결정하는 형질입니다. 완두에서 보라색과 흰색은 꽃 색깔 유전자자리(locus)에서 특정 유전자 변이(variant)(즉 대립유전자)에 의해 결정됩니다.
 
 <h4>퍼넷 사각형은 유전 정보를 구성하는 표입니다</h4>
 
 퍼넷 사각형의 각 상자는 두 부모 배우자(parental gamete) 사이에서 발생할 수 있는 수정(fertilization), 즉 자손의 유전자형(offspring genotype)을 나타냅니다. 퍼넷 사각형은 일반적으로 2x2 또는 4x4 구성으로 배열되어 각각 하나 또는 두 가지 형질의 유전을 시각화합니다.
 
 명명법(nomenclature)에 관해선, 대립유전자는 현성 대립유전자에 의해 발생하는 형질을 의미하는 (영어) 단어의 첫 글자로 표시됩니다. 예를 들어 노란색(영어로 yellow)은 완두 콩 색의 현성 형질이기 때문에, 완두 콩 색상을 나타내는 대립유전자는 이탤릭체 문자 ‘y’로 표시됩니다. 그리고 현성 대립유전자는 대문자로, 잠성 대립유전자는 소문자로 나타냅니다. 따라서 Y는 현성인 노란색 대립유전자를 나타내고, y는 잠성인 녹색 대립유전자를 나타냅니다.
 
 하나의 형질을 조사하는 2x2 퍼넷 사각형을 그려보자면, 일단 한 부모의 유전자형을 위의 그림처럼 열당 대립유전자 하나를 나열합니다. 다른 부모의 유전자형은 그림의 왼쪽처럼 수직으로 표시하고 행당 대립유전자 하나를 나열합니다. 각 퍼넷 사각형 상자에는 상자의 행과 열에 해당하는 두 부모의 대립유전자(즉, 각 부모로부터 하나)를 나열하며, 상자 하나는 일어날 수 있는 수정(fertilization) 결과 하나를 나타냅니다. 이렇게 채운 퍼넷 사각형을 사용해 자손이 특정 형질을 물려받을 가능성을 확인할 수 있습니다.
 
 <h4>퍼넷 사각형은 유전자상담자와 사육자를 위한 유익한 도구입니다</h4>
 
 100여 년 전에 만들어졌지만 퍼넷 사각형은 아직도 응용되고 있습니다. 유전 상담(genetic counseling)을 받는 사람의 경우 퍼넷 사각형은 아이들의 유전 질환 위험을 판단하는 데 도움이됩니다. 예를 들어 한 사람이 낭포성섬유증(cystic fibrosis; 2개의 잠성 대립유전자에서 발생)을 가졌지만, 그 사람의 반려자는 낭포성섬유증이 없고 원인이 되는 잠성 대립유전자도 가지고 있지 않은 경우, 둘 사이의 아이는 보인자(carrier; 즉 원인이 되는 잠성 대립유전자 하나를 가졌지만, 낭포성섬유증이 생길 위험은 없는 사람)가 됩니다. 퍼넷 사각형은 또한 동물과 식물 사육자가 번식을 지속하기 위해 특정 형질을 가진 개체를 선택하는 데 도움이 됩니다.
 
 퍼넷 사각형은 여러 맥락에서 유용하지만 복잡한 유전형식을 정확하게 묘사할 수 없습니다. 예를 들어 같은 염색체상의 인접한 유전자에 의해 암호화된 형질은 종종 하나의 부모로부터 함께 물려받는 연관(linkage)이라는 현상이 있습니다. 이러한 형질은 독립적으로 분류되지 않기 때문에 퍼넷 사각형으로 유전형식을 정확하게 예측할 수 없습니다. 키 같은 일부 형질은 여러 유전자에 의해 결정되며, 환경 조건(음식 등)의 영향을 받기 때문에 퍼넷 사각형에 적합하지 않습니다. 퍼넷 사각형은 한쪽 부모에게서만 얻어진 형질의 유전을 예측하는 데에도 효과가 없습니다.

개요

Punnett 사각형은 자손이 두 개의 부모 유전자형에서 물려받을 수 있는 가능한 유전자형을 표시합니다. 특성의 상속 패턴이 ...

Education

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Biology

생물학

Genetics

유전학

Classical and Modern Genetics

고전 유전학과 현대 유전학

KEY TERMS AND CONCEPTS

주요 용어 및 개념

punnett squares for predicting traits

Punnett squares help predict which traits offspring may inherit from two parents. They show possible genotypes, which are pairs of alleles, and can also show the chance of a phenotype, or visible trait, when the inheritance pattern is known. These grids work best for traits controlled by a single gene locus and passed on independently during meiosis.

Punnett squares were developed in the early 1900s by Reginald Punnett. His work came after Gregor Mendel’s pea plant experiments revealed the basic laws of inheritance. Mendel studied traits such as pea and pod shape and color, flower color and position, and plant size. For flower color, purple and white are different traits controlled by different alleles at the same gene locus.

A Punnett square organizes genetic information in a grid. Each box represents one possible fertilization event, or one possible offspring genotype, from two parental gametes. These diagrams are often shown as 2x2 squares for one trait or 4x4 squares for two traits. Alleles are usually written with the first letter of the dominant trait. For pea color, Y stands for the dominant yellow allele, and y stands for the recessive green allele.

To build a 2x2 Punnett square, one parent’s genotype is placed across the top and the other parent’s genotype is placed down the side. One allele goes above each column, and one allele goes next to each row. The boxes then combine one allele from each parent. The full square shows the chances of each genotype and helps predict the trait an offspring may show.

Punnett squares still matter in genetics, counseling, and breeding. Genetic counselors can use them to estimate a child’s risk for inherited disease. For example, if one parent has cystic fibrosis and the other neither has nor carries it, the child will be a carrier but will not be at risk for cystic fibrosis. Breeders also use Punnett squares to choose organisms with useful traits for future breeding.

These grids do have limits. They do not work well for complex inheritance patterns, such as linked genes on the same chromosome, because those genes are not independently assorted. They are also not a good fit for traits like height, which can depend on several genes and environmental factors such as diet. Punnett squares are also not useful for traits acquired from only one parent.

Punnett Squares for Predicting Traits

genetic lingo

Genotype, Phenotype, and Inheritance

Genotype, phenotype, and inheritance help explain how traits and disease risk are passed from parents to offspring. In diploid organisms, including humans, most other animals, and many plants, somatic cells carry a duplicate set of chromosomes. These chromosome pairs are homologous, with similar length, centromere position, and gene locations. Diploid organisms inherit two versions of each gene, one from each parent. These versions are called alleles, and they sit at the same relative locus,...

punnett squares

Punnett squares help predict which traits offspring may inherit from two parents. They show possible genotypes, which are pairs of alleles, and can also show the chance of a phenotype, or visible trait, when the inheritance pattern is known. These grids work best for traits controlled by a single gene locus and passed on independently during meiosis. Punnett squares were developed in the early 1900s by Reginald Punnett. His work came after Gregor Mendel’s pea plant experiments revealed the...

monohybrid crosses

Mendel’s Pea Plant Inheritance Ratios

Gregor Mendel used pea plants to study how traits are passed from parents to offspring. His breeding experiments in the 1850s and 1860s showed that inheritance follows clear patterns. He crossed true-breeding plants that differed in one trait and found that dominant traits can hide recessive traits. Mendel focused on seven pea plant traits, and each trait had two forms controlled by a single gene locus. He noticed that true-breeding plants always produced offspring with the same phenotype, or...

dihybrid crosses

Mendel's Law of Independent Assortment

Mendel’s law of independent assortment explains how two traits can be inherited separately. Gregor Mendel tested this idea with pea plants that differed in two characteristics, such as pea color and pea shape. He used true-breeding parents that were homozygous for both traits but showed different phenotypes. In one example, Mendel crossed round, yellow peas with wrinkled, green peas. The parental generation had RRYY and rryy genotypes. Their first-generation offspring were all dihybrids,...

law of segregation

Mendel’s Pea Cross Ratios

Mendel’s pea plant crosses show how traits can disappear in one generation and return in the next. When he crossed plants, one parental trait sometimes seemed to vanish in the F1 generation and reappear in the F2 generation. Mendel used this pattern to explain why some traits are dominant and others are recessive. He proposed that traits are controlled by alleles, which are different versions of a gene. An organism inherits two copies of each gene, one from each parent. In his model, a...

law of independent assortment

Mendel’s Dihybrid Cross and Trait Ratios

Mendel’s dihybrid cross shows how two traits are inherited at the same time. A dihybrid cross is a cross in which both parents are homozygous for two distinct traits, and the F1 generation is heterozygous for both traits. Mendel used pea plants with round yellow peas and wrinkled green peas as an example. One parent had genotype YYRR, and the other had genotype yyrr. In the F1 generation, every plant showed the dominant traits, so the plants were YyRr and had yellow, round peas. The F2...

probability laws

Inheritance Risk with Sum and Product Rules

Inheritance risk can be calculated with the sum rule and the product rule. The sum rule applies to mutually exclusive events, or events that cannot happen at the same time. The product rule applies to independent events, or events that do not affect one another. These rules describe theoretical probability, which is the chance of an event before it happens. Empirical probability is different because it is based on events that have already occurred. These probability rules are useful in...

test cross

Using Test Crosses to Identify Genotypes

Test crosses are used to identify the genotype of an organism with a dominant trait. A genotype is the pair of alleles inherited for a gene, and alleles are different forms of the same gene. In diploid organisms, including humans, each gene usually has two alleles, one from each parent. An allele is recessive when its effect is hidden by another allele at the same gene location. Pea plants provide a clear example with flower color. White flowers are recessive, because one copy of the purple...

polygenic traits

Polygenic Traits in Human Height

Polygenic traits are traits controlled by more than one gene. Human height is a clear example of this kind of inheritance. Because many genes work together, the final trait can vary a lot from person to person. Researchers have found hundreds of loci, or gene locations, that influence height. There are likely many more that have not yet been identified. Many of these genes affect cartilage in the growth plates of the long bones in the arms and legs, either directly or indirectly. Height is...

pedigree analysis

Reading Family Traits in Pedigrees

Pedigrees are family trees used to track how a trait passes through generations. They help scientists and students see whether a trait is dominant or recessive, whether it is autosomal or sex-linked, what genotypes family members may have, and what phenotypes may appear in future generations. For families with a history of inherited disease, this information can be important for family planning. In plants and animals, inheritance is often studied with crosses. Monohybrid crosses can show...

multiple allele traits

Blood Type and Allele Interactions

Multiple alleles can shape traits through blood type, sickle cell anemia, incomplete dominance, and codominance. Multiple allelism means a gene has three or more allelic forms. Diploid organisms, including humans, usually carry only two alleles for each gene, but many human genes exist in multiple forms in the population. Human blood type is a clear example of multiple allelism. The blood type gene has three alleles: I A , I B , and i. These alleles help determine which blood type a person has...

epistasis

Gene Masking in Rabbit Fur Color

Epistasis describes how one gene can mask or change the effect of another gene. In high school genetics, this helps explain why many traits do not follow a simple single-gene pattern. Instead, alleles at different locations can work together to shape the final phenotype. Mendel studied seven unrelated pea traits, but most traits involve multiple gene interactions. Epistasis often happens when one gene interferes with the expression of another gene. It can also occur when genes are part of the...

nature and nurture

Genes and Environment Shape Height

Genes and environment both shape human height and other traits. Genes are the inherited instructions we get from our parents. Environment includes factors such as diet, stress, and social conditions. Many phenotypes, or observable traits, reflect both influences. Some also show up later in life, including cancer and other diseases. Height is a clear example of this interaction. Scientists estimate that 70-90% of height variation comes from genetic differences among people. The remaining 10-30%...

pleiotropy

SOX10 and Multiple Traits in Pleiotropy

Pleiotropy is when one gene affects more than one trait. The SOX10 gene is a clear example because it can influence pigmentation, hearing, and intestinal movement. These traits may seem unrelated, but they can all be linked to the same gene change. In humans, a deleted region in SOX10 can cause Waardenburg Syndrome Type 4, or WS4. WS4 is an autosomal recessive disorder, which means a person usually inherits two altered copies of the gene. Common signs include a white forelock,...

sex-linked disorders

X- and Y-Linked Disorder Patterns

X- and Y-linked disorders come from mutations in genes on the sex chromosomes. These genes, like those on autosomes, are needed for normal body function. When a mutation causes a biological problem, the condition is called sex-linked. Y-linked disorders come from changes in the Y chromosome. They affect only males, because only males carry a Y chromosome. Mutations in this small chromosome can affect male sexual function and secondary sex characteristics. One example is Y-chromosome...

x-linked traits

X-Linked Inheritance in Families

X-linked inheritance explains how traits on the X chromosome are passed through families. In most mammalian species, females have two X sex chromosomes, while males have one X and one Y. A mutation on one X chromosome may be masked in females by a normal allele on the other X. In males, that same mutation is more likely to show because there is no second normal X to balance it. Traits caused by changes on the X chromosome are called X-linked traits. Color blindness is a well-studied example.

x-inactivation

Barr Bodies and X-Chromosome Balance

Barr bodies and X-chromosome balance help explain how female mammalian cells control gene activity from the X chromosome. The human X chromosome carries far more genes than the Y chromosome. Because males usually have one X chromosome and females have two, females would make twice as many of some proteins without a control system. To prevent that imbalance, female mammalian cells inactivate nearly all the genes on one X chromosome during early embryonic development. The inactive X condenses...

non-nuclear inheritance

Maternal DNA in Mitochondria and Chloroplasts

Maternal DNA in mitochondria and chloroplasts explains how some genes are inherited outside the nucleus. Most DNA is in the nucleus, but mitochondria and chloroplasts in the cell cytoplasm also carry their own DNA and can copy it independently of nuclear DNA. Mitochondria are found in both plant and animal cells. They are called the powerhouses of eukaryotic cells because they break down glucose to make energy for cellular activity. Mitochondrial DNA has about 37 genes, and many help with...

chromosomal theory of inheritance

How Genes Map to Chromosomes

Genes map to chromosomes, and this idea explains how Mendel’s inheritance patterns work. Gregor Mendel published his pea plant breeding results in 1866. He showed that physical traits follow predictable patterns. At the time, scientists did not yet know that genes existed. Mendel used the word "factors" for the hereditary units he studied. The details behind Mendel’s laws of segregation and independent assortment were still unknown for many years. In the late 1800s, better microscopes and...

key terms and concepts

Learn how Punnett squares predict offspring genotypes and traits, from Mendel’s pea plants to genetic counseling, breeding, and simple inheritance patterns.

Punnett Squares for Predicting Traits | JoVE K12

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Next Generation Science Standards

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heredity-inheritance-and-variation-of-traits

Heredity: Inheritance and Variation of Traits

HS-LS3-1

new-york-state-science-learning-standards

New York State Science Learning Standards

Inheritance and Variation of Traits

HS-LS3-1.

Georgia Standards of Excellence

9-12

SB3.b

Florida Department of Education

SC.912.L.16

SC.912.L.16.1

myJoVE Corporation

The DNA Helix

Overview

Deoxyribonucleic acid, or DNA, is the genetic material responsible for passing traits from generation to generation in all organisms and most ...

DNA Packaging

Overview

Eukaryotes have large genomes compared to prokaryotes. In order to fit their genomes into a cell, eukaryotes must pack their DNA tightly inside ...

Organization of Genes

Overview

The genomes of eukaryotes can be structured in several functional categories. A strand of DNA is comprised of genes and intergenic regions. ...

Replication in Prokaryotes

Overview

DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins bind to ...

Replication in Eukaryotes

Overview

In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high ...

Proofreading

Synthesis of new DNA molecules starts when DNA polymerase links nucleotides together in a sequence that is complementary to the template DNA strand. DNA ...

Mutations

Overview

Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. ...

Transcription

Overview
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene ...

Translation

Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following ...

Bacterial Transformation

In 1928, bacteriologist Frederick Griffith worked on a vaccine for pneumonia, which is caused by Streptococcus pneumoniae bacteria. Griffith studied two ...

What is Gene Expression?

Overview
Gene expression is the process in which DNA&nbsp;directs the synthesis of functional products, that is, proteins. Cells can regulate gene ...

The Central Dogma

Overview

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

Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of ...

RNA Structure

Overview
The basic structure of RNA consists of a five-carbon sugar and one of four nitrogenous bases. Although most RNA is single-stranded, it can form ...

RNA Stability

Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations ...

Types of RNA

Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs ...

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns&mdash;non-coding regions of a gene&mdash;or intergenic regions&mdash;stretches of DNA ...

RNA Splicing

Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called ...

Epigenetic Regulation

Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like ...

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its ...

Operons

Prokaryotes can control gene expression through operons&mdash;DNA sequences consisting of regulatory elements and clustered, functionally related ...

Proteins: From Genes to Degradation

The student will investigate and understand that organisms reproduce and transmit genetic information to new generations. Key ideas include DNA has a role in making proteins that determine organism traits;

LS.10.a

What is Meiosis?

Meiosis is the process by which diploid cells divide to produce haploid daughter cells. In humans, each diploid cell contains 46 chromosomes, half from ...

Meiosis I

Meiosis is a carefully orchestrated set of cell divisions, the goal of which&#x2014;in humans&#x2014;is to produce haploid sperm or eggs, each containing ...

Meiosis II

Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 ...

Crossing Over

Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where ...

Nondisjunction

During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed ...

The student will investigate and understand that organisms reproduce and transmit genetic information to new generations. Key ideas include the role of meiosis is to transfer traits to the next generation; and

LS.10.b

Genetic Lingo

Overview

An organism is diploid if it inherits two variants, or alleles, of each gene, one from each parent. These two alleles constitute the genotype ...

Overview

A Punnett square displays the possible genotypes offspring can inherit from two parental genotypes. If a trait&#x2019;s inheritance pattern ...

Monohybrid Crosses

Overview

In the 1850s and 1860s, Gregor Mendel investigated inheritance by performing monohybrid crosses in pea plants. He crossed two plants that were ...

Dihybrid Crosses

Overview

To determine whether traits are inherited together or separately, Gregor Mendel crossed pea plants that differed in two traits. These parental ...

Law of Segregation

When crossing pea plants, Mendel noticed that one of the parental traits would sometimes disappear in the first generation of offspring, called the F1 ...

Law of Independent Assortment

While Mendel&#x2019;s Law of Segregation states that the two alleles for one gene are separated into different gametes, a different question of how ...

Test Cross

Alleles are different forms of the same gene. Humans and other diploid organisms inherit two alleles of every gene, one from each parent.

An allele is ...

Pedigree Analysis

Overview

A pedigree is a diagram displaying a family&#x2019;s history of a trait. Analyzing pedigrees can reveal (1) whether a trait is dominant or ...

X-linked Traits

In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be ...

Sex-linked Disorders

Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological ...

Nature and Nurture

Many human characteristics, like height, are shaped by both nature&mdash;in other words, by our genes&mdash;and by nurture, or our environment. For ...

The student will investigate and understand that organisms reproduce and transmit genetic information to new generations. Key ideas include Punnett squares are mathematical models used to predict the probability of traits in offspring.

Punnett Squares for Predicting Traits

Description

Transcript

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