Mometrix TEAS 7 science practice test

Correct Answer: A

Rationale: B cells are responsible for immunological memory. Memory B cells, a type of B cells, retain a 'memory' of specific pathogens, enabling them to rapidly produce antibodies upon re-exposure. This rapid antibody production facilitates a quicker and more effective immune response. Although memory T cells also contribute to immunological memory by mounting a swift and robust immune response upon re-exposure to the pathogen, it is primarily memory B cells that play a crucial role in producing antibodies. Phagocytes are important immune cells involved in engulfing and digesting pathogens, while natural killer cells are primarily responsible for recognizing and eliminating abnormal cells, such as virus-infected cells or tumor cells. However, when it comes to immunological memory and antibody production, B cells are key players.

Correct Answer: B

Rationale: The Hardy-Weinberg equilibrium describes a theoretical population in which allele frequencies remain constant from generation to generation, indicating that the population is not evolving. This equilibrium occurs under specific conditions: no mutation, no gene flow, random mating, a large population size, and no natural selection. In this scenario, all genotypes are in proportion to the allele frequencies, and genetic diversity is maintained. Options A, C, and D do not accurately describe a population in Hardy-Weinberg equilibrium. Option A suggests rapid evolution due to strong directional selection, which would disrupt the equilibrium. Option C mentions a founder effect, which can reduce genetic diversity but is not a characteristic of a population in Hardy-Weinberg equilibrium. Option D describes a population dominated by a single homozygous genotype, which also does not align with the genetic diversity seen in a population at Hardy-Weinberg equilibrium.

Correct Answer: A

Rationale: The correct answer is Growth hormone (GH). GH, produced by the pituitary gland, is responsible for stimulating the growth and development of bones, muscles, and organs. It plays a critical role in regulating growth during childhood and adolescence by promoting cell division, protein synthesis, and tissue growth. Thyroid-stimulating hormone (TSH) functions to stimulate the thyroid gland to produce thyroid hormones, while prolactin is involved in milk production. Follicle-stimulating hormone (FSH) is primarily responsible for reproductive functions like egg development in females and sperm production in males.

Correct Answer: B

Rationale: During the S phase of interphase, DNA replication takes place. DNA polymerase is the enzyme responsible for synthesizing new DNA strands by adding nucleotides in a complementary manner to the template strand. It plays a pivotal role in accurately replicating the entire genome. While helicase unwinds the double-stranded DNA for replication, topoisomerase relieves the tension in the DNA strands, and ligase joins the Okazaki fragments on the lagging strand. However, DNA polymerase directly participates in the synthesis of new DNA strands during replication, making it the correct answer.

Correct Answer: D

Rationale: Newton's rings are a series of concentric colored rings observed when light is reflected between a spherical surface and a flat surface. This phenomenon is a result of thin-film interference, where light waves reflecting off the two surfaces interfere with each other constructively or destructively, leading to the observed pattern of rings. Diffraction, polarization, and the Doppler effect are not related to the specific phenomenon of Newton's rings. Diffraction refers to the bending of waves around obstacles, polarization deals with the orientation of electromagnetic waves, and the Doppler effect relates to the change in frequency of waves due to motion. Therefore, the correct answer is thin-film interference, as it precisely describes the phenomenon observed in Newton's rings.