MCAT Biology Systems EK Exam Questions and Answers

MCAT Biology Systems EK Exam Questions and Answers Protista, Fungi, Plantae, and Animalia all fall under domain? - Correct Answer️️ - Eukarya All mammals belong to the class ____________ and the phylum _________. - Correct Answer️️ -Mammalia; Chordata Define the cell theory - Correct Answer️️ -The cell is the smallest basic unit of life and is shared by all living things. The average eukaryotic cell is __________ Mm - Correct Answer️️ -10-100 What is the difference between genotype and phenotype? - Correct Answer️️ - Genotype= chromosomes of an organism phenotype= the product of genes What are alleles? - Correct Answer️️ -A form of gene. I.e white flower gene (allele 1) purple flower gene (allele 2) Same gene, diff colors. A gene that has multiple alleles, with different phenotypes is called? - Correct Answer️️ -polymorphism The __________ _________ is the total of all alleles in a population and _____________ is a change in a population's gene pool. - Correct Answer️️ -gene pool; evolution What is speciation? - Correct Answer️️ -The formation of a new species What mechanisms contribute to speciation? - Correct Answer️️ -1. Inbreeding (mating of relatives) 2. Bottleneck ( differences of allelic frequencies between populations) 3. Specialization and adaptation How does inbreeding contribute to speciation? - Correct Answer️️ -When relatives mate, it increases the homozygous individuals in a population without changing the allele frequency, if the population is geographically divided into groups and a mutation arises in one group but not the other than it leads to speciation. What is outbreeding? - Correct Answer️️ -Mating between non-relatives, maintains genetic flow What is the bottleneck theory? - Correct Answer️️ -reduction in the size of a population due to environmental events ( earthquakes, floods, fires, etc) In what conditions would evolution fail to occur according to Hardy-Weinberg equilibrium? - Correct Answer️️ -1. mutational equilibrium 2. large population 3. random mating 4. immigration or emigration must not change the gene pool 5. No selection for the fittest organism How can evolution be measured? - Correct Answer️️ -by grad