Тест: Genetics Fundamentals and Inheritance — 9 въпроса

1. What is deoxyribonucleic acid mainly responsible for in living organisms?

A. Building cell membranes from lipids

B. Breaking down nutrients to release energy

C. Carrying hereditary information organized into segments that determine traits

D. Transporting oxygen in the bloodstream

Answer: (C)

Обяснение

DNA is the molecule that carries hereditary information in living organisms. Its sequence is organized into segments, including genes, that determine traits.

2. What is the primary role of deoxyribonucleic acid (DNA) in living organisms?

A. It stores and transmits genetic information

B. It serves as a structural component of cell membranes

C. It produces energy for cellular activities

D. It catalyzes biochemical reactions within the cell

Answer: (A)

Обяснение

DNA is the molecule that stores and transmits genetic information necessary for inheritance and cellular function. The other options describe roles of other molecules like ATP, lipids, and enzymes.

3. What is a gene?

A. A sugar-phosphate unit that makes up the DNA backbone

B. A complete chromosome made only of proteins

C. A temporary copy of DNA used during cell division

D. A segment of DNA containing the information needed to produce a functional product

Answer: (D)

Обяснение

A gene is a segment of DNA that contains the information needed to produce a functional product, most often a protein. The other choices describe a nucleotide, a chromosome, or a copy process.

4. What is the primary function of chromosomes in a cell?

A. To synthesize proteins directly from amino acids

B. To produce energy through cellular respiration

C. To serve as the site of DNA replication during cell division

D. To store genetic information and organize genes within the cell

Answer: (D)

Обяснение

Chromosomes primarily serve to store and organize genetic information within the cell, carrying the genes that determine the organism's traits. The other options describe different cellular functions not directly related to chromosomes.

5. Which components make up a DNA nucleotide?

A. A protein and a lipid

B. A nitrogenous base and an amino acid

C. A sugar, a phosphate group, and a nitrogenous base

D. Two sugars and a phosphate group

Answer: (C)

Обяснение

A DNA nucleotide is composed of a sugar, a phosphate group, and a nitrogenous base. This is the basic unit of DNA.

6. When are the chromosomes most actively involved in the process of distributing genetic material during cell division?

A. During transcription, when genes are turned into RNA.

B. During cell growth phases, when chromosomes are synthesized.

C. During mitosis and meiosis, when chromosomes are segregated to daughter cells.

D. During DNA replication, when chromosomes are duplicated.

Answer: (C)

Обяснение

Chromosomes are most actively involved in distributing genetic material during mitosis and meiosis, when they are segregated into daughter cells. DNA replication occurs prior to this process, not during.

7. What is the main outcome of DNA replication before cell division?

A. One DNA molecule that loses half of its bases

B. Two identical DNA molecules, each with one old strand and one new strand

C. A protein chain that carries the genetic code

D. Two DNA molecules made only of newly synthesized strands

Answer: (B)

Обяснение

Replication produces two identical DNA molecules, each containing one original strand and one newly synthesized strand. This semi-conservative copying helps preserve genetic information.

8. How does mendelian inheritance differ from genetic mutation in the transmission of characters?

A. Mendelian inheritance causes new DNA variations, whereas mutations follow specific rules of allele combinations.

B. Mendelian inheritance involves the predictable transmission of alleles, while mutations are random changes in DNA that can alter alleles.

C. Mendelian inheritance only affects dominant traits, but mutations can influence both dominant and recessive traits.

D. Mutations are inherited in a predictable manner according to Mendel's laws, while Mendelian inheritance results from spontaneous DNA changes.

Answer: (B)

Обяснение

Mendelian inheritance refers to the predictable passing of alleles based on genetic rules, whereas mutations are random changes in DNA that can create new alleles and potentially alter traits.

9. Who is credited with proposing the fundamental principles of the genetic inheritance laws that describe the transmission of characters from parents to offspring?

A. James Watson

B. Charles Darwin

C. Gregor Mendel

D. Francis Crick

Answer: (C)

Обяснение

Gregor Mendel is credited with proposing the fundamental laws of inheritance, which describe how traits are transmitted through genes and alleles. The others contributed to evolutionary theory or molecular biology but not the laws of inheritance.