Nokea
Which statement accurately describes the head of a phospholipid?
- A. It is hydrophilic.
- B. It is hydrophobic.
- C. It is located on the outer side of the layer.
- D. Both A and C
Correct Answer: D
Rationale: The head of a phospholipid is hydrophilic, meaning it is attracted to water. This property allows the head to interact with water molecules. Additionally, the head is positioned on the outer side of the lipid bilayer in cell membranes, facing the watery environments inside and outside the cell. As a result, the correct answer is 'Both A and C,' as the head of a phospholipid is both hydrophilic and located on the outer side of the layer.
You may also like to solve these questions
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.
Which term means a group of similar cells combined to perform a common function?
- A. Tissue
- B. System.
- C. Organism.
- D. Organ.
Correct Answer: A
Rationale:
Which of the following is not an RNA base?
- A. Adenine
- B. Thymine
- C. Uracil
- D. Cytosine
Correct Answer: B
Rationale: In RNA, the bases are Adenine, Uracil, and Cytosine. Thymine is uniquely found in DNA and not RNA. Adenine pairs with Uracil, while Cytosine pairs with Guanine in RNA. Thus, Thymine is not an RNA base, making it the correct answer.
How many different types of nucleotides are there in DNA?
- A. one
- B. two
- C. four
- D. eight
Correct Answer: C
Rationale: The correct answer is C: four. DNA is composed of four different types of nucleotides: adenine (A), thymine (T), cytosine (C), and guanine (G). These nucleotides pair specifically (A with T and C with G) to form the double-stranded DNA structure.
Which of the following cell parts are present in plant cells but not animal cells (there may be more than one answer):
- A. Cell membrane
- B. Cell wall
- C. Ribosome
- D. Chloroplast
Correct Answer: D
Rationale: The correct answer is 'D - Chloroplast' because it is a unique cell part found only in plant cells and is responsible for photosynthesis. Animal cells do not possess chloroplasts. Both plant and animal cells have cell membranes, which are essential for cellular function. The cell wall is a structural component specific to plant cells, providing support and protection. Ribosomes, responsible for protein synthesis, are organelles present in both plant and animal cells.