Biology Semester 1 Exam 24

Front

What is the structure of DNA?

Back

DNA is a double helix made up of two strands of nucleotides, which consist of a phosphate group, a sugar (deoxyribose), and nitrogenous bases (adenine, thymine, cytosine, guanine).

Front

What is the role of hydrogen bonds in DNA?

Back

Hydrogen bonds form between complementary nitrogenous bases (adenine with thymine, and cytosine with guanine), holding the two strands of DNA together.

Front

What happens during the G1 phase of the cell cycle?

Back

During the G1 phase, the cell grows, synthesizes proteins, and prepares for DNA replication.

Front

What is the significance of DNA replication?

Back

DNA replication ensures that each daughter cell receives an exact copy of the parent cell's DNA during cell division.

Front

What occurs during the G2 phase of the cell cycle?

Back

During the G2 phase, the cell continues to grow and prepares for mitosis, including the replication of organelles.

Front

What are the main stages of mitosis?

Back

The main stages of mitosis are prophase, metaphase, anaphase, and telophase.

Front

What is the function of checkpoints in the cell cycle?

Back

Checkpoints monitor the cell's progress and ensure that it meets the necessary criteria to proceed to the next stage.

Front

What is the role of centrioles during cell division?

Back

Centrioles help organize the mitotic spindle, which separates chromosomes during mitosis.

Front

What is a bacteriophage?

Back

A bacteriophage is a type of virus that specifically infects bacteria.

Front

How do viruses differ from living cells?

Back

Viruses lack cellular structures and cannot reproduce independently; they require a host cell to replicate.