Nokea
Human cells need oxygen for respiration. What system of the body is responsible for transporting an oxygen molecule to different locations throughout the body?
- A. Skeletal.
- B. Lymphatic.
- C. Respiratory.
- D. Circulatory.
Correct Answer: D
Rationale:
You may also like to solve these questions
Based on the information provided, what would be the phenotype if the offspring is Bb?
- A. Black
- B. Black and tan
- C. Tan
- D. Not enough information
Correct Answer: A
Rationale: In genetics, when the offspring is Bb, it represents a heterozygous genotype with 'B' denoting black color. In this scenario, 'black' would be the phenotype displayed by the offspring. The dominant allele 'B' for black color would mask the recessive allele 'b,' resulting in the expression of the black phenotype.
In a population of dogs, fur color is controlled by two alleles: black (B) and tan (b). The black allele shows complete dominance. If a dog has a tan fur phenotype, what is its genotype?
- A. BB
- B. Bb
- C. bb
- D. Not enough information
Correct Answer: C
Rationale: If a dog displays a tan fur phenotype, it indicates that the dog possesses two tan alleles, represented by the genotype bb. In this case, the dog cannot have any black alleles (B) since the black allele demonstrates complete dominance over the tan allele. Therefore, the correct genotype for a dog with a tan fur phenotype is bb.
Which of the following describes how a bacterium reproduces?
- A. Mitosis
- B. Meiosis
- C. Binary fission
- D. Cytokinesis
Correct Answer: C
Rationale: Binary fission is the correct answer. Bacteria reproduce asexually through binary fission, where a single cell divides into two identical daughter cells. Mitosis and meiosis are processes that occur in eukaryotic cells, not bacteria. Cytokinesis is the physical division of the cytoplasm that follows nuclear division, which is a part of the cell cycle in both eukaryotic and prokaryotic cells but not specific to bacterial reproduction.
Why is the nucleus important in a cell?
- A. It stores the DNA.
- B. It provides structural support.
- C. It synthesizes proteins.
- D. It produces energy from food.
Correct Answer: A
Rationale: The correct answer is A. The nucleus is crucial in a cell because it stores the DNA, which contains the genetic information necessary for directing the cell's activities and determining its characteristics. The nucleus does not provide structural support, synthesize proteins, or produce energy from food; these functions are carried out by other cell organelles. Therefore, the main role of the nucleus is to safeguard and regulate the genetic material of the cell, ensuring proper cell function and inheritance of traits.
How is the aerodynamic nature of a bird's wing best categorized in biology?
- A. Organisms and their environment
- B. Ontogeny
- C. Structure and function
- D. Heredity
Correct Answer: C
Rationale: The aerodynamic nature of a bird's wing exemplifies the relationship between its structure and its function, showcasing how its form is intricately adapted for its function of flight. This concept of the interdependence of structure and function is a fundamental theme in biology. It emphasizes how the structures of living organisms are precisely designed to carry out specific functions, thereby influencing their survival and success in their respective environments.