Cell Cycle and Stem Cells

This set of flashcards covers essential concepts related to the cell cycle, stem cells, their functions, and implications in biology and medicine.

What are chromosomes made up of?

Chromosomes consist of DNA molecules combined with proteins and contain genes for protein synthesis.

How are chromosomes arranged in the nucleus of a body cell?

Chromosomes are arranged in pairs, forming 23 pairs, with a total of 46 chromosomes.

What are the three main stages of the cell cycle?

1. Replication of DNA and synthesis of organelles, 2. Mitosis, 3. Division of cell.

Why is mitosis important?

Mitosis is important because it produces identical cells with the same genetic information and creates additional cells for growth and repair.

Describe the first stage of the cell cycle.

The first stage is the longest, where cells grow, increase in mass, replicate DNA, and synthesize organelles.

Describe the second stage of the cell cycle.

In the second stage, each chromosome in a pair is pulled to opposite poles of the cell, then the nucleus divides.

Describe the third stage of the cell cycle.

The third stage involves the division of the cytoplasm and cell membrane, resulting in two identical daughter cells.

What is a stem cell?

A stem cell is an unspecialized cell capable of differentiating into other cell types and capable of self-renewal.

What is the function of stem cells in embryos?

Embryonic stem cells can replicate and differentiate into various cell types, potentially treating conditions like paralysis and diabetes.

What is the function of stem cells in adult bone marrow?

Adult stem cells can differentiate into several cell types to replace dead or damaged tissues, like forming different types of blood cells.

What is the function of stem cells in plant meristems?

Meristem stem cells can differentiate into any type of plant cell throughout their lifespan as needed by the plant.

What is therapeutic cloning?

Therapeutic cloning is a method producing an embryo with the same genetic makeup as the patient, allowing for non-rejection by the immune system.

What are the advantages of cloning plants using meristem stem cells?

1. Prevents rare plants from extinction, 2. Produces large numbers of favorable characteristic plants, 3. Creates identical plants for research.

What ethical issues are associated with the use of stem cells?

Ethical issues include the sourcing of embryonic stem cells from aborted embryos, which can conflict with some people's beliefs.

What are some challenges faced in the development of stem cell therapies?

The development process is slow, expensive, and difficult.

What risk is associated with adult stem cells infected with viruses?

Infected adult stem cells could transfer the infections to patients.

What is a potential risk regarding donor stem cells and patients?

If donor stem cells do not have a similar genetic makeup to the patient, it could trigger an immune response.

How do stem cells in embryos relate to medical treatment?

Embryonic stem cells have the potential to replace damaged cells in medical treatments.

What is the significance of organelles during the cell cycle?

Organelles are synthesized during the first stage of the cell cycle to support cell function.

What happens to chromosomes during mitosis?

During mitosis, chromosomes line up at the cell's equator before being pulled to opposite poles.

How many chromosomes are found in human body cells?

Human body cells typically contain 46 chromosomes organized into 23 pairs.

What is self-renewal in stem cells?

Self-renewal refers to the ability of stem cells to replicate themselves.

What is the role of stem cells in tissue damage?

Stem cells help in repairing damaged tissues by differentiating into the necessary cell types.

Why is cloning of plants beneficial for agriculture?

Cloning can produce uniform crops for better quality control in agriculture.

How do stem cells contribute to research?

Identical plants created from stem cells are valuable for controlled research experiments.

What are some potential medical uses for embryonic stem cells?

Potential uses include treating injuries and degenerative diseases.

What types of cells can adult stem cells differentiate into?

Adult stem cells can differentiate into various types of blood cells.

What are the implications of meristematic stem cells?

Meristematic stem cells offer potential for continuous plant growth and development.

Why might ethical concerns arise in therapeutic cloning?

Ethical concerns arise due to the sourcing of embryos and the implications of cloning technology.

What distinguishes stem cells from specialized cells?

Stem cells are unspecialized, while specialized cells have distinct functions.

What is the significance of chromosome pairing in body cells?

Chromosome pairing is crucial for genetic stability and proper cell division.

What is a characteristic of stem cells in plants compared to animals?

Plant stem cells retain the ability to differentiate into various cell types throughout their life.

How does DNA replication occur in the cell cycle?

DNA replication occurs during the first stage of the cell cycle.