the largest bone in the human body is the

ATI TEAS 7

ati teas 7 science

1. What is the largest bone in the human body?

A. Femur (thigh bone)
B. Tibia (shin bone)
C. Humerus (upper arm bone)
D. Scapula (shoulder blade)

Correct answer: A

Rationale: The femur, also known as the thigh bone, holds the title of the largest bone in the human body. Situated in the upper leg, the femur plays a vital role in supporting the body's weight and enabling movement. While the tibia (shin bone), humerus (upper arm bone), and scapula (shoulder blade) are all essential bones, none of them match the femur in terms of size and importance. The tibia, humerus, and scapula are comparatively smaller bones with specific functions in their respective areas of the body, but they do not surpass the femur in size or significance.

2. Which of the following infectious diseases can be caused by a protozoan parasite?

A. Measles
B. Malaria
C. Mumps
D. Mononucleosis

Correct answer: B

Rationale: The correct answer is B: Malaria. Malaria is caused by Plasmodium, a protozoan parasite transmitted through the bite of infected mosquitoes. Measles and mumps are viral diseases caused by separate viruses. Mononucleosis, on the other hand, is caused by the Epstein-Barr virus, which is also a viral infection. Therefore, choices A, C, and D are incorrect as they are caused by viruses, not protozoa.

3. Which of the following is NOT a source of genetic variation in a population?

A. Mutations in genes
B. Genetic drift (random fluctuations in allele frequencies)
C. Gene flow (movement of genes between populations)
D. Blending inheritance (traits of parents are averaged in offspring)

Correct answer: D

Rationale: Rationale: A) Mutations in genes: Mutations are changes in the DNA sequence that can introduce new alleles into a population, leading to genetic variation. B) Genetic drift (random fluctuations in allele frequencies): Genetic drift refers to random changes in allele frequencies in a population, which can lead to genetic variation through chance events. C) Gene flow (movement of genes between populations): Gene flow occurs when individuals move between populations, bringing new alleles with them and increasing genetic variation within populations. D) Blending inheritance (traits of parents are averaged in offspring): Blending inheritance was a historical theory that suggested offspring inherit a blend of traits from their parents, leading to a reduction in genetic variation over time. However, this concept has been disproven by the understanding of Mendelian genetics, where traits are inherited independently and do not blend together. Therefore, blending inheritance does not contribute

4. Antibiotic resistance in bacteria is an example of:

A. Convergent evolution
B. Divergent evolution
C. Microevolution
D. Macroevolution

Correct answer: C

Rationale: Antibiotic resistance in bacteria is a classic example of microevolution (option C). Microevolution refers to changes in allele frequencies within a population over a relatively short period of time. In the case of antibiotic resistance, bacteria evolve resistance to antibiotics through the natural selection of pre-existing resistant strains. This process does not involve the formation of new species or higher taxonomic groups, which are associated with macroevolution (option D). Convergent evolution (option A) involves different species independently evolving similar traits in response to similar environmental pressures, which is not the case with antibiotic resistance in bacteria. Divergent evolution (option B) refers to related species becoming more dissimilar over time, which also does not apply to the scenario of antibiotic resistance in bacteria.

5. What are the two primary functions of the respiratory system?

A. Delivering nutrients and removing CO2
B. Delivering O2 and removing CO2, maintaining blood pH
C. Maintaining blood pH and delivering nutrients
D. Delivering O2 and nutrients to the cells

Correct answer: B

Rationale: The correct answer is B. The respiratory system's primary functions include delivering oxygen (O2) to the body's cells for cellular respiration and removing carbon dioxide (CO2), thereby aiding in the maintenance of blood pH. These functions are crucial for gas exchange and the overall metabolic processes within the body. Choice A is incorrect as the respiratory system primarily delivers O2, not nutrients, and removes CO2, not delivering it. Choice C is incorrect as while the respiratory system helps maintain blood pH by removing CO2, it does not primarily deliver nutrients. Choice D is incorrect as it combines the functions of delivering O2 and nutrients, which are distinct roles of different systems in the body.