BS Bachelor of Science: Intro to Life Sciences 4 — Questions and Answers
Question 1: Which stage of mitosis is characterized by chromosomes aligning along the cell's equatorial plane?
- Prophase
- Metaphase (Correct answer)
- Anaphase
- Telophase
Correct answer: Metaphase
During metaphase, chromosomes are aligned at the metaphase plate by spindle fibers before separation.
Question 2: A solution that causes cells to shrink due to water loss by osmosis is described as:
- Hypotonic
- Isotonic
- Hypertonic (Correct answer)
- Isosmotic
Correct answer: Hypertonic
A hypertonic solution has a higher solute concentration than the cell, causing water to move out by osmosis.
Question 3: In the central dogma of molecular biology, what is the correct order of information flow?
- RNA → DNA → Protein
- DNA → Protein → RNA
- DNA → RNA → Protein (Correct answer)
- Protein → RNA → DNA
Correct answer: DNA → RNA → Protein
The central dogma states that genetic information flows from DNA to RNA (transcription) to protein (translation).
Question 4: Which type of symbiosis benefits both participating species?
- Parasitism
- Commensalism
- Mutualism (Correct answer)
- Amensalism
Correct answer: Mutualism
Mutualism is a symbiotic relationship where both species gain a fitness benefit from the interaction.
Question 5: What is the term for the full set of genetic material (all chromosomes) contained in a cell of an organism?
- Genotype
- Phenotype
- Proteome
- Genome (Correct answer)
Correct answer: Genome
The genome encompasses all genetic information encoded in an organism's DNA, including all chromosomes.
Question 6: Which enzyme unwinds the DNA double helix during replication by breaking hydrogen bonds between base pairs?
- DNA polymerase
- Ligase
- Helicase (Correct answer)
- Primase
Correct answer: Helicase
Helicase uses ATP to unwind and separate the two DNA strands at the replication fork.
Question 7: The region of a chromosome where spindle fibers attach during cell division is called the:
- Telomere
- Centromere (Correct answer)
- Chromatid
- Nucleosome
Correct answer: Centromere
The centromere is the constricted region of a chromosome where kinetochore proteins attach to spindle microtubules.
BS Bachelor of Science: Intro to Life Sciences 4
Which stage of mitosis is characterized by chromosomes aligning along the cell's equatorial plane?