False, changes in genes due to mutations can be beneficial. (An example would be polar bears. They had a genetic mutation that gave them their white fur. Therefore, they blended in with snow easier, ate more food, survived longer, and passed down their genetics, while those without the mutation died out.)
Answer:
d) a polypeptide missing an amino acid.
Explanation:
Deletion is a type of mutation when one or more codons from the reading frame are removed. This results in the production of a relatively shorter mRNA that lacks one or more codons otherwise present in the non-mutated mRNA. When there is a deletion of a single codon in the gene for cystic fibrosis, the resultant shorter mRNA codes for a polypeptide chain that does not carry one amino acid. For example, deletion of one codon results in deletion of a Phe residue present at position 508 in CFTR. The mutated transmembrane protein CFTR folds in an improper way.
Answer: Wrist
Explanation: The wrist connects the hand to the forearm. It consists of the distal ends of the radius and ulna bones, eight carpal bones, and the proximal ends of five metacarpal bones. This arrangement of bones allows for a wide range of movement.
When humans taste or smell, receptors unique to each nerve cell detect the chemical and send signals to the brain, where many cells process the message to understand what we are smelling or tasting. But a bacterium is just a single cell, and it must use many different receptors to sense and interpret everything around it.
When using a dichotomous key you look for the QUALITATIVE and QUANTITATIVE attributes of your specimen. Qualitative meaning the simple appearance such as color or the size. Quantitative meaning height, wings or no wings, tail or no tail, etc.
Hope this helps
