Name________________________________ Period ____________ Date ____________ Genetics and Reproduction CRCT Review Pg 74-75 1. _____________ is the chemical that contains information for an organism’s growth and functions. The structure resembles a twisted ladder or a _______________________. 2. In eukaryotic cells, most of the cell’s DNA is located in the _______________________. 3. DNA is wrapped around ______________________ like thread around a spool and compacted into structures called ______________________. Pg. 88-89 1. __________________________ is when one organism produces one or more new organisms that are identical to itself. 2. ___________________________ is a form of asexual reproduction occurring in prokaryotes. Pg 92 1. List 4 characteristics of asexual reproduction 2. List 4 characteristics of sexual reproduction Pg. 102 and 103 1. During __________________________ a cell containing genetic information from two parents combine into a completely new cell, becoming the offspring. 2. A ____________ is a unit of heredity that occupies a specific location on a chromosome and codes for a particular product. 3. ______________________ is the passing of genes from parent to offspring. 4. ______________________ are alternate forms of the same gene. 5. Humans have ____ pairs of chromosomes, for a total of ________ chromosomes. Pg. 106 and 107 1. An organism’s _______________ describes the actual characteristic that can be observed. Examples would be: 2. _______________________ is the name for the genes an organism has. Sometimes your genes contain information that is not expressed in your phenotype. 3. A ______________ allele is one that is expressed only when two copies of it are present on the homologs. 4. A _______________ allele is one that is expressed in the phenotype even if only one copy is present in the genotype. In pine trees, long needles (L) are dominant over short needles (l). Cross a homozygous dominant plant with a plant that is heterozygous. What percentage of offspring will have long needles? __________ Circle the answer and put the page number and question number from the guided reading that correlates with the answer you selected next to each question for full credit. 1. The physical expression of a trait is called a. Genotype b. Phenotype c. Genetics d. Heredity 2. Where would you look to find a specific gene a. Cells b. Nuclei c. Chromosomes d. Traits 3.A horse with the genotype Hh mates with another horse whose genotype is hh. What is the chance that the horse will have a long mane? H=long mane, h=short mane. a. b. c. d. 25% 50% 75% 0% 4. If red flowers (R) are dominate over white flowers (r), what ratio of the off spring will be homozygous recessive for the white trait if you cross a purebred white flower with a hybrid? a. b. c. d. 1 out of 4 2 out of 4 3 out of 4 0 out of 4 5. Which of the following would be an example of selective breeding a. A bacterium that is resistant to antibacterial soap passes this trait to offspring through binary fission. b. A farmer that crossbreeds only his largest corn stalks in order to produce more product to sell. c. A mutated beetle has benefited from a new camouflage trait and survives long enough to pass this beneficial trait to its offspring. d. All of the above are examples of selective breeding. 6. Which of the following traits of a human could have been inherited by parents? a. b. c. d. A southern accent from living in the southern regions of the United States Larger muscles The ability to swim well Having blue eyes 7. Which organism listed reproduces by binary fission? a. Green algae b. E-coli c. Trees d. Insects 8. Which of the following is a trait a. b. c. d. Eye color Heart rate Eating habits A and C 9. A species has 16 pairs of chromosomes. How many chromosomes would be in a sperm cell of this species? a. 16 b. 24 c. 32 d. 8 10. Each version of a particular gene is called a. An allele b. Dominant c. Recessive d. DNA 11. Why do farmers, scientists, and breeders practice selective breeding? a. b. c. d. To practice manipulating genes To produce organisms with desirable traits To reduce wastes To increase genetic diversity 12. Which statement is most accurate? a. The alleles for a gene must be identical for that trait to be expressed. b. The alleles for a gene may or may not be identical c. The alleles for a gene cannot be identical; if they are, the trait they code for will not be expressed. d. The alleles for most traits come from the female plant. 13. Which statement is MOST accurate? a. b. c. d. Organisms produced by asexual reproduction are genetically identical to the parent. In sexual reproduction, offspring get genes from only one parent. C. In asexual reproduction, offspring get about half their genes from each parent. Sperm and eggs have similar structures but different functions. 14. Which kind of organism never has an offspring that is unlike either parent? a. Plant b. Bacteria c. Protist d. Animal 15. Which cell contains half the usual number of chromosomes? a. Zygote b. Diploid cell c. Gamete d. Homolog