Test Prep Test Prep Certifications OAT Questions & Answers

• Question 121:

  If red hair is dominant over black hair, what is the expected phenotypic ratio of the F1 generation of red hair to black hair if a homozygous dominant breed with a heterozygous?

  A. 100% black hair

  B. 75% red hair; 25% black hair

  C. 50% red hair; 50% black hair

  D. 75% black hair; 25% red hair

  E. 100% red hair

  Correct Answer: E

  This is a simple monohybrid cross. Assume `R' for the dominant red hair and `r' for the recessive black hair.

  

  From this cross, it is obvious to see all the offspring will have red hair.

• Question 122:

  Which of the following arises from the mesoderm?

  A. Pancreas

  B. Lining of digestive system

  C. Skin

  D. Skeletal muscles

  E. Nervous system

  Correct Answer: D

  The mesoderm gives rise to muscle, bone and connective tissue.

• Question 123:

  The alveolus in lungs is an example of what type of what type of tissue?

  A. Simple squamous epithelial tissue

  B. Stratified squamous epithelial tissue

  C. Cuboidal epithelial tissue

  D. Columnar epithelial tissue

  E. Connective tissue

  Correct Answer: A

  The alveoli in lungs is a single layer of tissues of squamous epithelial. If it were multilayered, it would be stratified squamous epithelial tissue. Cuboidal epithelial tissues can be found in walls of tubules (ex. kidney tubules).

• Question 124:

  A female has 45 chromosomes, possessing only one X chromosome. She is sterile with no tangible ovaries. What condition does she possess?

  A. Klinefelter syndrome

  B. Turner syndrome

  C. Trisomy 21

  D. Patau syndrome

  E. Cri du chat syndrome

  Correct Answer: B

  This is indeed the definition of the Turner syndrome.

• Question 125:

  Which of the following types of muscles possesses striations?

  A. Skeletal

  B. Smooth

  C. Cardiac

  D. A and B

  E. A and C

  Correct Answer: E

  Both skeletal and cardiac muscles do possess striations, but skeletal have more defined striations.

• Question 126:

  A red flower is crossed with a white flower and produces a progeny consisting of 100% pink flowers. This is an example of?

  A. Incomplete dominance

  B. Co-dominance

  C. Epistasis

  D. Pleitropy

  E. Complementation

  Correct Answer: A

  When the progeny is a hybrid characteristic of the parentals, this is indeed incomplete dominance. Co-dominance can refer to blood types (A and B) whereas epistasis is one gene making the phenotypic expression of a second gene.

• Question 127:

  The air one inhales and exhales at a default, steady pace at rest is called:

  A. Tidal Volume

  B. Inspiratory Reserve Volume

  C. Expiratory Reserve Volume

  D. Total Lung Capacity

  E. Respiration

  Correct Answer: A

  This is the correct definition of tidal volume. This is measured via a spirometer.

• Question 128:

  Identify the incorrect pairing of hormone to site of secretion:

  A. Glucagon – alpha cells

  B. Angiotensinogen – liver

  C. GnRH – anterior pituitary

  D. TRH – hypothalamus

  E. Oxytocin – posterior pituitary

  Correct Answer: C

  GnRH is releases from the hypothalamus, not the anterior pituitary.

• Question 129:

  How much ATP is produced in the tricarboxylic acid cycle under aerobic conditions?

  A. 24

  B. 26

  C. 2

  D. 12

  E. 18

  Correct Answer: A

  Under the TCA cycle, 2 ATP are produced under substrate-level phosphorylation, 18 ATP are produced under oxidative phosphorylation (with 6 NADH) and 4 ATP are produced from oxidative phosphorylation (with 2 FADH2), adding up to a total of 24 ATP produced in the TCA cycle.

• Question 130:

  The separation of two annealed nucleic acid strands (ex. in preparation of DNA replication) can be accomplished by which of the following enzymes?

  A. DNA Polymerase I

  B. DNA Polymerase III

  C. Ligase

  D. Helicase

  E. Lipase

  Correct Answer: D

  Helicase is an enzyme that functions in unpackaging or separating 2 things (e.x. DNA strands).