Question

The following statements apply to concepts and material discussed in Chapter 15; identify which statement is TRUE.

Answers: A common ancestor of two species on evolutionary trees can be found at the point where the two branches meet. Humans evolved from Neanderthals about 50,000 years ago. Mitochondrial DNA is not particularly useful when trying to determine the movement pattern of humans historically across the globe. Scientists can estimate when species diverged from a common ancestor by comparing their Karyotypes. We humans share very few genes in common with any other animal species; it is what makes us unique.

Identify the term CORRECTLY paired with a corresponding definition.

Answers: Dihybrid Cross - Cross fertilization of two parents plants that have two different phenotypes. Epistasis - when individuals have the same genotype but express different symptoms. Pleiotropy - when one gene has many effects on different body systems. Reading frame - a series of 3 DNA nucleotides transcribed into a protein by DNA polymerase. Sex-Influenced Trait - a trait that affects a structure or function present in just one sex.

The following statements apply to concepts and material discussed in Chapter 12; identify which statement is TRUE.

Answers: A duplication of 3 bases would result in a frameshift mutation. Mutations always have harmful effects. Mutations are more common in nuclear DNA than in mtDNA. Segments of DNA with a long series of repeated bases are mutational hot spots. Somatic mutations occur during DNA replication and are based down from parent to offspring.

The following statements apply to concepts and material discussed in Chapter 6; identify which statement is TRUE.

Answers: If a disorder is X-linked recessive, we typically see that symptoms are more serious in women than in men. If a mother and daughter have the same genotype, but only the mother suffers from symptoms associated with an X-linked condition, this is due to X Inactivation. When an X-linked trait is recessive in women, but dominant in men, we refer to this as Sex-limited. When women need two copies of a faulty gene to show symptoms of Polycystic Ovarian Sydrome, but men don't have the disorder we call this a Sex-influenced condition. X chromosomes only have genes that affect "sexual" traits.

The following statements apply to concepts and material discussed in Chapter 9; identify which statement is TRUE.

Answers: DNA consists of two nucleotide chains arranged in the same direction coiled into a helix. DNA is directional, because one strand runs antiparallel to the other in a double helix. DNA replication involves making a copy of a parent strand, so the cell can keep its original strand in-tact. DNA replication requires DNA polymerase to read a strand of mRNA 3 bases at a time to determine base-pairing rules. When DNA Polymerase makes an error during replication, a primer comes in to fix it.

Identify the term CORRECTLY paired with a corresponding definition.

Answers: Crossing-over - The exchange of genes between the gametes of two different sexes. Homologous Chromosomes - Identical strands of genetic information that control trait expression. Introns - Parts of genes that are expressed as phenotypes. Quantitative Trait Loci - DNA sequences passed on only maternally. STRs - a short segment of DNA with a series of repeated nucleotides.

The following statements apply to concepts and material discussed in Chapter 2; identify which statement is TRUE.

Answers: Cell cycle checkpoints are important because they repair DNA errors. DNA Replication occurs during Mitosis. Mitosis is an error-free process. Stem cells are unique because they are capable of self-renewal and are undifferentiated. The goal of Mitosis is to split the genome to create 2 identical daughter cells.

Answer 1

1. In a phylogenetic tree, common ancestor is known as internal nodes where two branches meet and hence, option a is correct.

2. (Sex) influenced trait are affect only one (sex). Hence, option e is correct.

3. The mutation are common more in nuclear DNA than the mitochondria DNA. Hence, option c is correct.

4. (Sex ) limited traits are present in both male and female but express only in one. Hence, correct option is c.

5. STR stand for short tandem repeats and are short repeats found in DNA. Hence, correct option is e.

6. Stem cell are unique because they have a ability to self-renew . Hence, option d is correct.