Review The passing of traits from parents to offspring is called ______. heredity The different forms of a trait that a gene may have are called _____. alleles The study of how traits are inherited is the science of _____. genetics In a Punnet square, the letters stand for ______. A. dominant alleles B. recessive alleles C. both a and b D. neither a nor b C The genetic makeup of an organism is called its _____. genotype The way an organism looks and behaves as a result of its genetic makeup is called its _____. phenotype In a Punnett square, a capital letter (T) stands for a _____ allele. dominant The combination Tt represents a _____ genotype. A. heterozygous B. homozygous C. purebred D. recessive A Experiments with four o’clock flowers produced examples of _____ dominance. incomplete Blood type is an example of ______. A. multiple alleles B. a pair of genes C. polygenic inheritance D. sex-linked genes A Color blindness is an example of _____. A. a sex-linked disorder B. incomplete dominance C. a genetic disorder D. polygenic inheritance A Genetic engineering has already helped people by _____. A. altering pedigrees B. curing Down’s syndrome C. eliminating infant deaths D. producing medicine D Through recombinant DNA, scientist have been able to _____. A. cure color blindness B. create new breeds of dogs C. alter viruses D. improve tomatoes D Who is known as the father of genetics? Gregor Mendel Organisms that receive different alleles from each parent are called _____. hybrids What term describes an organism with two alleles that are the same? homozygous What term describes an organism with two different alleles for a trait? heterozygous What term describes a group of gene pairs acting together to produce a trait? polygenic inheritance Errors occurring in the DNA when it is copied inside a cell are called _____. mutations The passing of traits from parents to offspring is called _____. heredity The different forms of a trait that a gene may have are called _____. alleles In a Punnett square, the letters stand for ______ and _____ alleles. dominant, recessive The genetic makeup of an organism is called its _____. genotype The way an organism looks and behaves as a result of its genetic makeup is called its _____. phenotype Vocabulary passing of traits from one generation to another heredity inserting DNA into bacteria recombinant DNA study of inheritance genetics an allele inherited on a sex chromosome sex-linked gene a trait that is hidden recessive the chance that an event will take place probability genetic makeup of an organism genotype a normal allele is placed into a virus gene therapy physical appearance resulting from genotype phenotype both alleles are express in offspring incomplete dominance more than one set of genes controls a trait polygenic inheritance True/False Genetic engineering is the practice of changing the arrangement of DNA through biological and chemical methods. True In gene therapy a normal allele is placed in a virus, which delivers the allele when it infects its target cell. True An allele inherited on a sex chromosome is called a sex-linked disorder. False, sexlinked gene Environmental influences cannot have an impact on phenotype. False, can Environmental influences can be internal or external. True Gregor Mendel was the first experimenter to trace one trait through several generations. True Mendel called plants that had received different alleles for a trait from each parent genes. False, hybrids A given allele’s effect is dominant or recessive. True An organism with two alleles that are the same is called heterozygous. Multiple Answers False, homozygous An organism that has two different alleles for a trait is called homozygous. False, heterozygous A trait produced by a combination of many genes is called polygenic. True Multi point question Create a Punnet Square where the father is homozygous dominate for cleft chin and mother is homozygous recessive for no cleft chin. What are the genotypes and phenotypes for their offspring? Create a Punnet Square where the father is heterozygous for dominate dimples and the mother is heterozygous for dominate dimples. What are the genotypes and phenotypes for their offspring?