CBA #4 Practice Exam Genetics 1) (TEKS 5A) Which of the diagrams below shows the process of transcription: 2) (TEKS 5C) All of the following are true statements about cell differentiation EXCEPT A. Cell differentiation is when all cells have the same structure and function B. Cell differentiation is having groups of cells with different structures and functions C. A zygote which eventually produces many types of cells, such as somatic and germ cells, represents cell differentiation D. DNA regulates the process of cell differentiation
3) (TEKS 5C) The figure below depicts the overall process of cloning in mammals. During this procedure, the nuclei from one cell (egg cell from sheep B) is destroyed or removed and the nucleus or DNA from sheep A is then transferred to the de-nucleated egg cell. Knowing that the transplanted DNA will function as the original nuclear DNA of the egg cell, what will the end result be? A. A sheep with characteristics of both Sheep A and Sheep B B. A sheep that is identical to Sheep B C. A sheep that is identical to Sheep A D. A sheep that is identical to Sheep C Use the figure below to answer the following question: 4) (TEKS 6A) Which arrow is pointing to a component which helps to make up the genetic code? A. B. C. D.
5) (TEKS 6B) In bacterial cells (seen below on the left) the genetic code ACG codes for the amino acid Threonine. If a human cell (seen below on the right) had the genetic code ACG, which amino acid would it code for? (A codon chart can be found on the last page) A. Cystenine B. Threonine C. Alanine D. Arginine 6) (TEKS 6C) Nitrogenous bases of DNA are what make up the genetic code of an organism. The sequences of these bases vary widely and are the instructions for determining the organism s unique and complex traits. How does the DNA code actually produce the unique and complex traits of an organism? A. DNA transcribes itself to messenger RNA in the nucleus which is then translated with the help of trna in ribosomes to form amino acids which create proteins. B. DNA is transcribed in the ribosomes where it then creates RNA C. DNA is translated to messenger RNA which is then transcribed into amino acids to create proteins D. DNA moves from the nucleus to the ribosomes to deliver the code and produce proteins 7) (TEKS 6D) Gene regulation is when certain genes are turned off or on in a cell. Which of the following is an example of gene regulation being influenced by environmental factors? A. Different wing colors seen in butterflies based on the light it was exposed to as a caterpillar. B. The development of cardiac muscle cells to form the heart C. Nerve cells forming the brain during early embryonic development D. Blue eyes being expressed in an individual who has two blue eyed parents
Use the information below and codon chart on the last page to answer the following two questions Many inherited diseases are the result of a genetic change in one or more chromosomes. The following substitution mutation has occurred in a gamete cell: Original DNA sequence AATGCGCATAGG Mutated DNA sequence AACGCGCATAGG 8) (TEKS 6E) All of the following statements are true EXCEPT A. The triplet produced in the mutated strand will still code for the same amino acid, so the synthesized protein will have the same structure and function and will likely not affect the cell or organism B. The mutated base sequence code will produce a defective protein C. The individual with this mutation may pass it on to their offspring and to every cell that develops from that gamete cell D. Changing the mutated DNA sequence to AAAGCGCATAGG will affect the protein produced 9) (TEKS 6E) What amino acids are produced by the mutated DNA sequence (in the correct order)? A. Leucine, Arginine, Valine, Serine B. Serine, Valine, Arginine, Leucine C. Asparagine, Alanine, Histidine, Arginine D. Arginine, Histidine, Alanine, Asparagine Use the information below to answer questions 10-12 In humans, dimples are dominant (D) to not having dimples (d), and freckles are dominant (F) over not having freckles (f). If a man with the genotype ddff and a woman with the genotype DdFF get married and have children 10) (TEKS 6F) What is the probability of producing offspring with the DdFF genotype? A. 0% B. 25% C. 50% D. 75%
11) (TEKS 6F) What is the expected phenotypic outcome in the offspring for the freckle gene? A. 75% freckles, 25% no freckles B. 100% freckles C. 100% no freckles D. 50% freckles, 50% no freckles 12) (TEKS 6F) What is the expected genotypic ratio for the dimpled gene? A. 0 DD: 2 Dd: 2 dd B. 1 DD: 2 Dd: 1 dd C. 2 DD: 0 Dd: 2 dd D. 2 DD: 1 Dd: 0 dd 13) (TEKS 6G) The following statements are true about mitosis and meiosis EXCEPT 14) (TEKS 6H) Scientist often use model organisms such as mice to study human genetic diseases. If a scientist wanted to find out if their mouse contained a specific gene, which genetic test should they perform? A. karyotyping B. chromosome painting C. DNA fingerprinting D. recombinant DNA 15) (TEKS 6H) A picture of a person s karyotype is shown below. Along with showing the presence of an additional or missing chromosome, what else can best be determined by examining this person s karyotype? A. mitosis produces two identical diploid daughter cells with the same number of chromosomes as the original parent cell B. meiosis produces haploid gamete cells with a reduced number of chromosomes than the parent cell C. meiosis produces four fertilized gamete cells D. genetic variation is increased during meiosis when crossing-over occurs A. The presence of a homozygous genotype B. The person s genome C. The person s gender D. The person s phenotype
TEKS that you will be tested on: 5A- describe the stages of the cell cycle, including deoxyribonucleic acid (DNA) replication and mitosis, and the importance of the cell cycle to the growth of organisms 5C- describe the roles of DNA, ribonucleic acid (RNA), and environmental factors in cell differentiation 6A- identify components of DNA, and describe how information for specifying the traits of an organism is carried in the DNA 6B- recognize that components that make up the genetic code are common to all organisms 6C- explain the purpose and process of transcription and translation using models of DNA and RNA 6D- recognize that gene expression is a regulated process 6E- identify and illustrate changes in DNA and evaluate the significance of these changes 6F- predict possible outcomes of various genetic combinations such as monohybrid crosses, dihybrid crosses and non-mendelian inheritance 6G- recognize the significance of meiosis to sexual reproduction 6H- describe how techniques such as DNA fingerprinting, genetic modifications, and chromosomal analysis are used to study the genomes of organism