Make a Punnett square, using each of the gametes for one parent across the top of each column, those of the other parent go vertically. Law of Independent Assortment – law states that genes/alleles separate independently of one another in meiosis (Mendel’s dihybrid cross based on this law) Law of Segregation – law states that alleles on homologous chromosomes are separated from each. In addition the above alleles (red & brown), you will use a blue B" and green "b" alleles. pdf FREE PDF DOWNLOAD Dihybrid Cross Problem Set - The Biology Project Answer key to practice problems -- Genetics 371B. Worksheet: Dihybrid Crosses U N I T 3 : G E N E T I C S STEP 1: Determine what kind of problem you are trying to solve. A pea plant which is homozygous round seed and has green seed color is crossed with a pea plant that is heterozygous round seed shape and heterozygous yellow seed color. ) * Each characteristic is determined by a…. 2500 F1 8 11 5 0. Dihybrid Crosses the natural progression for Mendel was to study 2 characteristics at the same time. Corn — a diploid organism — has been widely used to study and illustrate mendelian traits. Genetics is a complex field with lots of details to keep straight. cross of Charlie and the mother. spotted, which is a cross between a heterozygote (Ss) and a homozygous recessive (ss). Complete a Punnett Square for the cross Identify. You completed these last year. The question for you to answer is: are these traits dominant, co-dominant, or recessive? To do so, you will need the rhinoceros population data on page 4, your knowledge of genetic dominance, and the ability to perform dihybrid test crosses with Punnett Squares. Each trait still only has two possible genes, so the dihybrid Punnett square will be a grid with four rows and four columns and sixteen possible outcomes. In man, assume that spotted skin (B) is dominant over non-spotted skin (b) and that wooly hair (R) is dominant over non-wooly hair (r). Very little. Worksheet: Dihybrid Crosses. Contents provided in these pages are meant for general information only, and not suggested as replacement to standard references. warrencountyschools. Note the gametes that each parent can contribute 3. In Coleus, some plants have shallowly crenated edges and others have deeply incised leaves. Chapter 10 Dihybrid Cross Worksheet Answer Key Dihybrid Cross Worksheet Answer Key Worksheets for all from Chapter 10 Dihybrid Cross Worksheet Answer Key , source: bonlacfoods. Showing top 8 worksheets in the category spongebob science. From Genetics For Dummies, 2nd Edition. Make a "key" to show all the possible genotypes (and phenotypes) of this organism. If two heterozygotes have children, what is the chance that a child will have normal skin pigment?. Jean-Baptiste Lamarck introduced a theory about inheritance in the early 1800s. What others are saying This is a short quiz on the dihybrid or two factor genetics cross. Be sure to complete the Punnett square to show how you derived your solution. Students apply the principles of Mendelian genetics to analyze the results of genetic crosses. Here, I created a sample pedigree with a key for the eye color of the creatures: Key: Pedigree: _____ 4. • Mendel’s dihybrid crosses led to his second law, the law of independent assortment. Dominate allele for tall plants = D Recessive allele for dwarf plants = d Dominate allele for purple flowers = W Recessive allele for white flowers = w Cross a homozygous dominate parent (DDWW) with a homozygous recessive parent (ddww) 3. 2 Dihybrid. Single gene traits: Define: phenotype - the outward or physical expression of the genetic code of an organism genotype - the genetic code of an organism; which alleles are present dominant - the allele that determines the phenotype of a heterozygote and masks the expression of the recessive allele. STEP 4: Make your punnett square and make gametes STEP 5: Complete cross and determine possible offspring. Part 6: Dihybrid Cross E. Practice Dihybrid Crosses 1. This test is a great tool to assess a student's mastery of a Punnett Square unit. This worksheet also contains 8 easy steps for completing these types of problems. Download _____ BIO 1510 SI Worksheet Chapter 13 SI Leader: Erika Zwolinski 14. From Lehninger Principles of Biochemistry : The stability of YAC increases with size (up to a limit). An aquatic arthropod called a Cyclops has antennae that are either smooth or barbed. This Pea Plants Dihybrid Cross Worksheet is suitable for 8th - 10th Grade. What letter would you choose to represent the red and yellow alleles. What is the probability that the offspring will have black fur? [Answer should be a ratio. considered the acceptability of alternative answers. They have orange or gray faces, purple, red, or blue hair. STEP 5: Complete cross and determine possible offspring. When you cross hairless with each other, you get 1 normal to 2 hairless. Genetics Problems Genetics Problems 1. Answers to past exam questions. 4 Harmful – mutation that cause harm to the organism. These four beads represent the genotype of individual #1, record thisinformation. The Amazing Maize Investigating Dihybrid Crosses Gregor Johan Mendel (1822í1884) was a monk who discovered the fundamental principles of genetic traits. • All of the F 1 offspring were heterozygous dominant for round yellow peas (RrYy). All of the white-flowered progeny will be true breeding. Punnett square worksheet Complete the following monohybrid crosses: draw a Punnett square, list the ratio and describe the offspring. MENDELIAN GENETICS PROBLEMS AND ANSWERS PROBLEM 1. What would be the genotype for a tomato which has a yellow-flesh color? rr 3. AP Biology - Genetic Practice Problems Choose the answer which best completes each of the following statements or answers the following questions. In mice the ability to run normally is a dominant trait. 2) For each of the following write whether it is homozygous dominant, heterozygous or homozygous recessive. To carry out such a cross, each parent is chosen to be homozygous or true breeding for a given trait (locus). View 11 29 Dihybrid Cross practice answer key from BIOL 1108 at Georgia Gwinnett College. Similar to a Punnet square, a dihybrid cross tracks genetic traits passed from parents. 6 Mixed Review Problems · Unit Review 6. TT Tt Tt tt 12. B=brown (not albino) L=long tails. By Tara Rodden Robinson. These types of crosses are used to determine the proportion of possible offspring that would display a particular trait. A dihybrid cross is a cross between individuals homozygous for two genes. P (purple) and S (smooth) are dominant alleles, and p (yellow) and s (wrinkled) are recessive alleles. The first dominant trait along with the second recé)ssive trait? D. You can refer to the "Punnett Square Cheat Sheet" attached at the end of this worksheet to help you solve the different types of problems. Place the number corresponding to that response in the appropriate blank on your student answer sheet as well as on this paper. A homozygous tall plant is crossed with a short plant. The student will determine the genotypes of the parents, fill in the 16 box Punnett square, and answer questions about each problem. Dihybrid Crosses Worksheet Use the dihybrid cross below to answer questions 1 - 6: 1. One strategy is first to determine which of the four phenotypes represents a "pure line" (i. STEP 3: Determine parent's genotypes. STEP 3: Determine parent’s genotypes. The recessive trait causes mice to run in circles only. Instructions: For each problem, complete a dihybrid cross and calculate the ratios of each genotype. TIP: In any cross involving at least one parent that is homozygous dominant (2 CAPITAL letters), 100% of the offspring will have the dominant trait in their phenotype. Mendel’s Laws. Genetics Practice Problems - Simple Worksheet 1. This is described as inheritance. Many of these practice worksheets will include a dihybrid cross worksheet answer key so that you can practice yourself and be sure that you are doing them correctly. D) A monohybrid cross is performed for one generation, whereas a dihybrid cross is performed for two generations. Genetics. What percent of the offspring will be homozygous recessive? 6. So these right there, those are linked traits. Mice with this trait are called running mice (R). Genotype: The letters that make up the individual. By crossing with a homozygous recessive we can determine the dominant individuals genotype. So our answer to Question 1b is also: 0% would be short-whiskered. If a homozygous tall pea plant is crossed with a homozygous short pea plant, explain how the offspring always result in tall pea plants. Crosses That Involve 2 Traits 6. This is illustrated by Questions 1a & 1b. Conclusion: In this lab we learned the relationship that occurs when the mass of an object is increased while the net force is left constant. In the mean time we talk related with Dihybrid Cross Worksheet Answers, we've collected particular similar pictures to give you more ideas. In this video I will discuss setting up the ratios and percents of a punnett square. Pathki's leg. Complete a Punnett Square for the cross Identify. ) * Each characteristic is determined by a…. (Ex: FF = floppy ears; LL = normal legs) 2. Dihybrid Cross Worksheet Answer Key - wiildcreative Worksheets For All Download And Share Worksheets Free On Monohybrid Cross Worksheet Answer Key - Checks Worksheet monohybrid and dihybrid crosses worksheet with answers charlespeng. STEP 2: Determine letters you will use to specify traits. But when you get a handle on some key terms and concepts, including the structure of DNA and the laws of inheritance, you can start putting the pieces together for a better understanding of genetics. Dihybrid Cross Practice - key. A Cyclops that is resistant to pesticides and has smooth antennae is crossed with one that is heterozygous for both traits. At any time you help them by presenting an answer, it could lead to you personally making a living by going online. A Punnett square may be used to predict the possible genetic outcomes of a monohybrid cross based on probability. Objectives:. Here are a couple problems. What are the possible GAMETES this Reebop can produce? T t B b. Cross a plant that is homozygous green pods and terminal flowers with a plant that has yellow pods and is homozygous for axial flowers. Name all 8 eight characteristics of life. The parents of the F1 generation were homozygous small headed and homozygous large headed. Quiz & Worksheet - Characteristics of a Dihybrid Cross Defining key concepts - ensure that you can accurately. A Trihybrid Cross Example Using Mendel's Sweet Peas A trihybrid cross is between two individuals that are heterozygous for three different traits. Instructions: For each problem, complete a dihybrid cross and calculate the ratios of each genotype. A dihybrid cross involves two traits. Heterozygous. Set up the crosses using the rules and the letters from the other page. A commonly discussed Punnett Square is the dihybrid cross. In snapdragons, tallness (T) is dominant to dwarfness (t), while red flower color is due to gene (R) and white to its allele (r). Which is the recessive trait? Explain your answer. Complete a Punnett Square for the cross Identify. Sorry guys, refer to your dihybrid corn snake Punnett square for this one. mating between two individuals with different alleles for one trait Monohybrid Cross specific characteristic of an organism Trait a variant form of a gene Allele cross between two different alleles that differ in two observed traits Dihybrid Cross an organism that passes down certain phenotypic traits to its offspring True-breeding. Genotypes Phenotypes 6. Monohybrid v. How can you employ this knowledge to support and advise folk and concurrently brand your self and then make dough via internet? Related to dihybrid cross worksheet answer key, It should certainly be very simple to realise how telephone answering products and services are helping the economy these times. If you don't see any interesting for you, use our search form on bottom ↓. You completed these last year. A male guinea pig that is homozygous dominant for both traits is crossed with a female who has long hair and red eyes. MAKING MONOHYBRID CROSSES: What is the genotype of a HOMOZYGOUS YELLOW SEED plant?. Corn — a diploid organism — has been widely used to study and illustrate mendelian traits. Answer check 2) Complete the Genetic Traits Survey - Turn to the chart on page three and just complete the chart. What would the creature with the genotype EeAARRttFfLHX(n)X(n) look like? 2. State the genotype and phenotype of the plant that must be used as the test cross. Many of these practice worksheets will include a dihybrid cross worksheet answer key so that you can practice yourself and be sure that you are doing them correctly. Genetics Problems Worksheet 1. • Mendel’s dihybrid crosses led to his second law, the law of independent assortment. If two plants with green. Two purebreeding plants were crossed, one grown from a startchy seed and one from a sugary seed. Genetics Practice Problems #7 Dihybrid crosses KEY She marries a homozygous, normally pigmented man who is a taster but who has a mother that does not taste PTC. A dihybrid cross describes a mating experiment between. Section 2: DiHybrid Crosses Dihybrid crosses examine two unlinked (on different chromosomes) gene loci. STEP 4: Make your punnett square and make gametes STEP 5: Complete cross and determine possible offspring. Ex: Mendel crossed a homozygous plant with yellow round peas with a homozygous plant with green wrinkled peas. Leave all the homozygous recessive offspring unshaded. Dad is not freckled and he has a. T is a 2,000 pound n s of s. Be sure to complete the Punnett square to show how you derived your solution. STEP 3: Determine parent's genotypes. Worksheet Answers Worksheets for all from Chapter 10 Dihybrid Cross Worksheet Answer Key , source: bonlacfoods. Form hypotheses about genotypic and phenotypic ratios in the F2 generation of corn crosses. Identify what each of the numbered parts represents in the Punnett square below. avoid making tedious and difficult Punnett squares like in Fig. Don't foraet to answer the question within the problem. genotype; a test cross may be helpful. The trait is sex-linked on the X chromosome. 2) For each of the following write whether it is homozygous dominant, heterozygous or homozygous recessive. The Amazing Maize Investigating Dihybrid Crosses Gregor Johan Mendel (1822í1884) was a monk who discovered the fundamental principles of genetic traits. Select the correct group of biocontrol agents. spotted, which is a cross between a heterozygote (Ss) and a homozygous recessive (ss). homozygous heterozygous hybrid Law of Segregation monohybrid crosses dihybrid cross phenotypic ratio autosomes sex chromosomes sex-linked genes codominance Law of Independent Assortment I. • The law of independent assortment states that allele pairs separate independently of each other during meiosis. From Lehninger Principles of Biochemistry : The stability of YAC increases with size (up to a limit). SpongeBob’s aunt, who is a roundpants, has a cute stubby nose. They make up a third of the purple flowers. Monohybrid and Dihybrid Genetics Practice Problems (incomplete dominance, sex-linked, gene linkage, codominace) Monohybrids. Feb 3, 2014 - How to make Punnett squares cheat sheet. In humans the allele for albinism is recessive to the allele for normal skin pigmentation. o Phenotypic Ratio 2: o: Genotypic Ratio Parent. Which of the following accurately describes his Theory of Acquired Characteristics? a. A Widow’s Peak is dominant to a round hairline. If the father is homozygous recessive for attached ear lobes, his sperm always have the f allele. Now read the problem again. TT Tt Tt tt 12. 8; pay attention in class for an easier method. The student will determine the genotypes of the parents, fill in the 16 box Punnett square, and answer questions about each problem. Parents: _____ x _____. In one experiment, Mendel crossed a pea plant that bred true for axial flowers with a pea plant that bred true for terminal flowers. Worksheet For Number Name. DIHYBRID(CROSSES(WITH(DOMINANCE( Heredity Worksheet, answer key. Suppose that black hair (B) is dominant over blonde hair (b), and brown eyes (E) are dominant over blue eyes (e). STEP 4: Make your punnet square and make gametes (these go on the top and side of your punnett square. Part 6: Dihybrid Cross E. Under each major topic you will need to answer each question. Discuss their responses as a class, and guide the class through the following questions. allele can only be observed in the homozygous recessive phenotype. This quiz is about Punnett squares and DNA genetic genes. Problem 7: Homozygous offspring of a dihybrid cross - Find the correct answer to the multiple-choice, dihybrid cross question. One strategy is first to determine which of the four phenotypes represents a "pure line" (i. One allele required to show dominant and two required to show recessive. Gregor Mendel learned about heredity by conducting experiments on the heredity of seven true-breeding (homozygous) traits of pea plants. The parents of the F1 generation were homozygous small headed and homozygous large headed. This type of genetic analysis can also be performed in a dihybrid cross, a genetic cross between parental generations that differ in two traits. Part C: Monohybrid Cross Problems - Show your work. This detail from an ear of corn illustrates the outcome of a dihybrid cross of parent plants that were heterozygous for kernel color and kernel form. A dihybrid Punnett square shows the possible crosses of two traits at the same time. Which is the recessive trait? Explain your answer. is a key trait you can identify them by. dominant (purebred). Multiple Choice Review - Mendelian Genetics & Inheritance Patterns 1. mendel answers key. Cross a pure breeding yellow plant with a green plant. This means you should have a total of eight problems written out and solved: monohybrid cross, working backwards, test (back) cross, dihybrid cross,. A cross of f1 hybrid plants. Short Answer & Free response. There are three problems on this quiz. Get Your Custom Essay on Biology Lab Report “Independent Assortment & Dihybrid Cross” Just from $13,9/Page Get Essay In this laboratory experiment we will count and score the phenotypes of Drosophila melanogaster from a F2 generation of a dihybrid cross involving loci on the two major autosomes, chromosome two and three. GENETICS PRACTICE 1: BASIC MENDELIAN GENETICS Solve these genetics problems. Review: Cross a heterozygous male for tallness with a homozygous recessive female for. CODOMINANCE. Complete a punnett square and determine the genotypic and phenotypic ratios. The expected ratio is 3:1, but with a sample size of four kittens, we shouldn't take this very seriously. Homework Practice: Students will be challenged to write their own dihybrid cross practice problem as homework. An answer key is also included for the guided notes and practice problems! It will make this specific genetics topic very easy for the teacher to teach, and the students to understand. 1) Complete the practice Dihybrid Cross Questions - you can self correct the questions here and then hand into the sub with the corrections and the questions that you have. Genetics is a complex field with lots of details to keep straight. In the following passage, you will be introduced to monohybrid and dihybrid crosses, two types of. Worksheet For Number Name. His work focused on plant breeding projects. BBtt x bbTT = 100% BbTt Black Trotter. Mixed Genetics Practice Problems Part of the difficulty of this unit is knowing what type of problems you are being asked to solve and being able to solve it correctly. ONE-FACTOR CROSSES Crosses that involve one trait, such as seed coat color, are called one-factor crosses. The Amazing Maize Investigating Dihybrid Crosses Gregor Johan Mendel (1822í1884) was a monk who discovered the fundamental principles of genetic traits. STEP 5: Complete cross and determine possible offspring. Directions: Complete the following Dihybrid Cross problems. What ratio of genotypes would result? Show your work. Predicting the Results of Monohybrid and Dihybrid Crosses - [14 pages] slide show about crosses in the form of a. #Thesecondlitter. A homozygous hornless bull is mated with a homozygous horned cow. Pure colored seed coat x white seed coat cc PI CC cc 6. Mendelian Genetics in Corn INTRODUCTION Mendelian traits refer to phenotypical features whose pattern of inheritance follows Mendel's theories about the inheritance of traits. Be able to make a Punnett square for monohybrid cross, and write the genotypic and phenotypic ratios. 5th Grade Fractions. Unlike a monohybrid cross, a dihybrid cross deals with two traits. Multiple Choice (only one answer is correct). His work was published in 1866 but was not noticed and recognized for its brilliance until the turn of the twentieth century. In each cross, record the number of progeny displaying each phenotype. How do the Punnett squares for a monohybrid cross and a dihybrid cross differ? 5. round yellow seeds X wrinkled green seeds. What are the possible GAMETES this Reebop can produce? T t B b. How can you employ this knowledge to support and advise folk and concurrently brand your self and then make dough via internet? Related to dihybrid cross worksheet answer key, It should certainly be very simple to realise how telephone answering products and services are helping the economy these times. The Making of the Fittest: Natural Selection in Humans e. ) When either of these traits was studied individually, the phenotypes segregated in the classical 3:1 ratio among the progeny of a monohybrid cross (Figure 6. Year 7 Maths Worksheets Qld. A plant that is homozygous for. reconstructing society. Phenotypic Ratio. After completing the lab, I learned how to use a punnett square and observed how it is similar to a multiplication table. The law of segregation – You can’t have the same letters in a Sex cell. Practice with Monohybrid Punnett Squares Read the following passage and answer the questions. Cross a heterozygous running, heterozygous black mouse with a homozygous running, homozygous black mouse. The allele for barbs is dominant. Punnett Squares Answer Key 1. A Punnett square simulates two organisms reproducing sexually, examining just one of the many genes that get passed on. Dihybrid cross worksheet Name - upsd. monohybrid heterozygous-heterozygous cross c. What would be the genotypic and phenotypic ratios of a mono-hybrid cross for. #Thesecondlitter. The allele for barbs is dominant. Select the correct group of biocontrol agents. Art Connection. Biology 30 Genetics. chromosomes, representing 50% cross over. A Punnett square is a chart used to predict the genotype (genetic characteristics) and the If we are predicting the probability of two traits, it is a dihybrid cross. Bikini Bottom – Dihybrid Crosses –Answer Key 1. A Dihybrid Cross. Mendel studied the following seven characters with contrasting traits:. MONOHYBRID DIHYBRID. Mar 116:32 PM •A homozygous tall pea plant that is homozygous for purple flowers is crossed with a. Example Problem. Monohybrid Punnett Squares. Dihybrid Crosses. striped squash (S) is dominant to spotted squash (s) If a. It would also be possible to designate the two alleles as W and w, and the three genotypes WW, Ww, and ww, the first two of which produced round peas and the third wrinkled peas. Different versions of a single gene are called cross between a homozygous dominant parent and a homozygous A dihybrid cross. TTorTt = tall tt = short GG or Gg = green gg = white. Monohybrid Cross Problems. Directions: Work the following problems out in your notebook or on a separate piece of paper. What are the genotypes of the parents? a. Worksheet: Dihybrid Crosses. Answer key where students practice their mastery of monohybrid crosses, incomplete dominance and dihybrids using oompa loompas as specimens for study. A homozygous yellow pea plant is crossed with a homozygous green pea plant, Yellow is the dominant trait for pea plants: A) Key: Y=yellow y=green B) Genotype of yellow pea plant: _ YY C) Genotype of green pea plant: __ yy _____ D) Draw the Punnett square of the cross Y Y y Yy Yy y Yy Yy. Be sure to complete the Punnett square to show how you derived your solution. You would use the combination of gametes from the crossing of two of those parent cells, then put those into the Punnett square to make a dihybrid cross showing the outcomes and probabilities for the offspring for these TWO traits. From the first two crosses (yellow x blue, yellow x red), and the 3:1 F2 ratio seen in them, it looks like a simple allelic series -- one gene with red, blue and yellow alleles, red and blue both being dominant over yellow. This Pea Plants Dihybrid Cross Worksheet is suitable for 8th - 10th Grade. com Genetics with spongebob dihybrid crosses with answer key - Paul. Example Producing dihybrids (F 1). ANSWER KEY Basic Genetics Practice. Hybrid eye shape, purebred roundpants _Rrss_____ 3. STEP 3: Determine parent's genotypes. Cross a male that is heterozygous for both traits with a female that is heterozygous for both traits. dihybrid heterozygous-heterozygous cross ____ 6. In maize starchy is dominant to sugary. A biology study guide reviewing a unit on Mendelian genetics. If a homozygous black pacer is mated to a homozygous chestnut trotter, what will be the appearance of the F1 generation? 3. Complete the Punnett Squares and answer the following questions. When looking at one trait at a time it is called a monohybrid cross. Koc unlimited food script Spongebob genetics dihybrid cross key lisdiboulehukons's Space - Home Spongebob genetics dihybrid cross key Genetics crosses answer key - Free Forum Hosting - Lefora. Here, I created a sample pedigree with a key for the eye color of the creatures: Key: Pedigree: _____ 4. Students need to include the following in their answer keys: Assign the parental genotypes for each. SpongeBob's aunt, who is a roundpants, has a cute stubby nose. testcross E. Lab 5 Answer Sheet Essay 698 Words | 3 Pages. An aquatic arthropod called a Cyclops has antennae that are either smooth or barbed. Complete the following crosses and give the genotypic and phenotypic ratios of offspring. Dihybrid Crosses: 1. Dihybrid Cross Definition. STEP 4: Make your punnet square and make gametes (these go on the top and side of your punnett square. Khan Academy - Complex Inheritance - Multiple Alleles, Codominance, Incomplete, Dihybrid Crosses Blood Type and Sex Linked Inheritance Practice Problems Answer KEY. FISH Genetics P ART B 1 Teacher's Instructions: 1) This is Part B of a three-part (A, B, C) project about Fish Genetics. Which of these Punnett squares would you use to show the possible offspring from this cross? MAKE THE FOLLOWING CROSS: T t B b X T t B b. Dihybrid crosses reveal the law of independent assortment ¥A dihybrid is an individual that is heterozygous at two genes ( YyRr) ¥Mendel designed experiments to determine if two genes segregate independently of one another in dihybrids ÐFirst constructed true breeding lines for both traits (YYRR & yyrr). What would the creature with the genotype EeAARRttFfLHX(n)X(n) look like? 2. A cross between two parent Reebops that are HETEROZYGOUS for TWO TRAITS is called a _____ cross. pdf Dihybrid Cross Tutorial to help answer the question. How to make Punnett squares cheat sheet Monohybrid. The student will determine the genotypes of the parents, fill in the 16 box Punnett square, and answer questions about each problem. Review: Cross a heterozygous male for tallness with a homozygous recessive female for. Then draw. Directions: Complete the following Dihybrid Cross problems. STEP 3: Determine parent's genotypes. B=brown (not albino) L=long tails. purple flowers? Possible genotype(s)? b. The Making of the Fittest: Natural Selection in Humans d. EXPERIMENT 3: MONOHYBRID CROSS AND DIHYBRID CROSS 1. Monohybrid Crosses -Complete Dominance For each of the following genetics problems, follow these steps in reaching a complete answer: Show all work. 5th Grade Fractions. A Trihybrid Cross Example Using Mendel's Sweet Peas A trihybrid cross is between two individuals that are heterozygous for three different traits. Genotype: The letters that make up the individual. MAIN IDEAS • Punnett squares illustrate genetic crosses. Monohybrid v.