Free BACE Genetics Questions and Answers — Questions and Answers
Question 1: What is the basic unit of heredity?
- Chromosome
- Gene (Correct answer)
- Protein
- DNA
Correct answer: Gene
A gene is the basic unit of heredity, consisting of a specific sequence of DNA (or RNA in some viruses). Each gene carries the instructions for making a specific protein or functional RNA molecule, which in turn determines a particular trait or characteristic. Genes are passed from parents to offspring, transmitting genetic information across generations.
Question 2: Which of the following best describes the structure of DNA?
- Single-stranded helix
- Double helix (Correct answer)
- Triple helix
- Circular molecule
Correct answer: Double helix
The structure of DNA is famously described as a double helix. This structure consists of two long polynucleotide strands coiled around a central axis, resembling a twisted ladder. The two strands are held together by hydrogen bonds between complementary nitrogenous bases (adenine with thymine, guanine with cytosine).
Question 3: What is the process by which DNA is copied into RNA?
- Replication
- Mutation
- Translation
- Transcription (Correct answer)
Correct answer: Transcription
Transcription is the process by which genetic information encoded in DNA is copied into a molecule of messenger RNA (mRNA). During transcription, an enzyme called RNA polymerase synthesizes an RNA strand that is complementary to a segment of the DNA template. This mRNA molecule then carries the genetic instructions out of the nucleus to the ribosomes for protein synthesis.
Question 4: What is the role of ribosomes in genetics?
- Storing genetic information
- Producing energy for the cell
- Synthesizing proteins (Correct answer)
- Copying DNA
Correct answer: Synthesizing proteins
Ribosomes are the cellular machinery responsible for synthesizing proteins, a process known as translation. They read the genetic code carried by messenger RNA (mRNA) and facilitate the assembly of amino acids into polypeptide chains. This function is central to gene expression, converting genetic information into functional proteins that carry out cellular tasks.
Question 5: Which type of RNA carries the genetic code from the nucleus to the ribosome?
- rRNA
- tRNA
- mRNA (Correct answer)
- siRNA
Correct answer: mRNA
Messenger RNA (mRNA) plays a crucial role in gene expression by carrying the genetic code from the DNA in the nucleus to the ribosomes in the cytoplasm. It acts as an intermediary, translating the DNA sequence into a sequence of codons that specify the order of amino acids for protein synthesis. Without mRNA, the genetic instructions stored in DNA could not be used to build proteins.
Free BACE Genetics Questions and Answers
What is the basic unit of heredity?