Principles Of Biology 1 (Sickle Cell Part 2)
16. CRISPR was discovered.
Answer: Accidentally, by scientists working with bacteria in the food industry. They were looking for ways to make cheese and yogurt production more effective.
6. During the human life cycle, the fertilization of an egg by a sperm results in.
Answer: A diploid zygote.
5. In humans, male gametes are called _____, while female gametes are called _____.
Answer: Sperm, Eggs.
15. CRISPR may work to treat sickle-cell disease by.
Answer: Targeting faulty portions of the hemoglobin gene within the genome of cells and removing and replacing those portions with normal sequences of nucleotides.
2. Variations in genes are called _____. Examples of these variations include eye color. There are blue eyes, green eyes, brown eyes, and several combinations of these.
Answer: Alleles.
17. A method of genome editing that uses the Cas9 enzyme to identify and cut specific nucleotides from the genome is called _____.
Answer: CRISPR (clustered regularly interspaced short palindromic repeats).
12. Susie is pregnant with her first child. Because of her advanced maternal age and a family history of various genetic disorders, her doctor has recommended genetic testing to ensure her offspring is healthy. Her doctor places a long thin suction tube through her vagina into the uterus, where it obtains fetal cells from the chorion of the developing embryo. These cells are then sent off for testing. What is this type of procedure called?
Answer: Chorionic Villus Sampling (CVS).
8. During prophase I of meiosis, genetic information is exchanged between two homologous chromosomes, resulting in new combinations of alleles. This process is called _____.
Answer: Crossing - Over.
13. Which of the following is the most effective means of treating or even curing sickle-cell disease?
Answer: Gene Therapy.
1. Which of the following best describes the definition of a gene?
Answer: Genetic information that produces a product, either proteins or RNA.
11. Images of unreplicated chromosomes that allow researchers to organize and identify each chromosome, as well as missing or extra chromosomes is called a(n) _____.
Answer: Karyotype.
9. Mendel's experiments led him to the conclusion that individuals have two factors for each trait that separate during gamete formation, resulting in gametes with one factor for each trait. In addition, fertilization results in a new individual with two factors for each trait again. He referred to this as the _____.
Answer: Law of segregation.
4. Meiosis is different from mitosis in that meiosis.
Answer: Results in four haploid daughter cells that are genetically diverse, whereas mitosis results in two diploid daughter cells that are genetically identical.
7. Meiosis proceeds different in males compared to females. Which of the following best describes one of those differences?
Answer: Spermatogenesis results in the production of four haploid sperm cells and oogenesis results in the production of a single haploid egg cell.
10. Sickle-cell disease is a recessive genetic disease. This means.
Answer: Two copies of the recessive allele must be present in order for the disease to be expressed.
14. During gene therapy, bone marrow stem cells are removed from the individual. What must happen to those cells before they are injected back into the individual?
Answer: Viruses act as vectors to carry the normal gene into the genome of the stem cells.
3. Humans have two sex chromosomes that are named based on their shape. Males have (a) _____ and females have (a) _____.
Answer: X and Y chromosome, two X chromosomes.