The autosomal CFTR gene encodes a transmembrane protein that transports chloride ions across membranes of cells that produce mucus, sweat, tears, saliva and digestive enzymes. A common mutation in this gene delta F508 results in one amino acid being deleted from the protein. This causes the mutant protein to not transport chloride ions as efficiently, so that mucus, sweat, and such are thick and sticky. People homozygous for the mutant allele have cystic fibrosis, but heterozygotes or wild-type homozygotes are unaffected. Select all the terms below that correctly describe this system. HINT: There are FOUR. haplosufficient wildtype allele haploinsufficient wildtype allele gain of function mutation loss of function mutation amorphic mutation hypomorphic mutation hypermorphic mutation neomorphic mutation codominance seen between the two alleles complete dominance seen between the two alleles incomplete dominance seen between the two alleles.

1. The average birth weight for human babies is about 3kg. Which of the following terms best
describes this? Disruptive selection. Stabilizing selection Artificial selection. Directional selection.
Question 30 Cattle breeders have improved the quality of meat over the years by which process?
Artificial Purifying Selection Artificial Directional Selection Artificial Stabilizing Selection Artificial
Disnuptive SelectionA plant biologist noticed that individuals of a plant species with the same
genotype grow to different heights across a gradient of sunlight in their greenhouse. This
mechanism that shows that individuals of the same genotype develop or behave differently when
they live in different environments is known as phenotypic plasticity. disruptive selection. adaptive
radiation. phenotype selection. Question 28 In seed cracker finches from Cameroon, small- and
large-billed birds specialize in cracking soft and hard seeds, respectively, If longterm climatic
change resulted in all seeds becoming hard, what type of selection would then operate on the
finch population? Directional selection. Sexual selection. Disruptive selection. Disruptive
selectionWhen we say that an individual organism has a greater fitness than another individual,
we specifically mean that the organism competes for resources more successfully than others of
its species. survives better and leaves more viable offspring than others of its species. utilizes
resources more efficiently than other species occupying similar niches. mates more frequently
than others of its species. Question 26 Which of the following selection patterns explain the
situation of an African butterfly species that exists in two strikingly different color patterns?
Directional selection. Disruptive selection. Artificial selection Stabilizing selection.Which of the
following best describes the impact of purifying selection? It increases frequency of an allele. It
increases genetic diversity. It is the same as disruptive selection. It removes variation from the
population. Question 24 Which statement about variation is true? Al genetic variation produces
phenotypic variation. All phenotypic variation is the result of genotypic variation. All nucleotide
variability results in neutral variation. All new alleles are the result of mutations