Cancer

• What are the main steps of the cell cycle?

  Interphase and Mitotic Phase
• How does DNA replication occur?

  It is semi-conservative, meaning each new DNA molecule contains one old and one new strand.
• Compare homologous chromosomes and sister chromatids.

  • Homologous chromosomes:
  • Matched pairs from each parent
  • Similar in size, centromere location, and function
  • Sister chromatids:
  • Identical copies of a chromosome
  • Formed during DNA replication
• What are the steps of mitosis and cytokinesis?

  1. Prophase: Chromosomes condense and spindle fibers form.
  2. Metaphase: Chromosomes align at the cell's equator.
  3. Anaphase: Sister chromatids are pulled apart.
  4. Telophase: Nuclear membranes reform around each set of chromosomes.
  5. Cytokinesis: Cytoplasm divides, forming two daughter cells.
• What are the main characteristics of cancerous cells?

  Cancerous cells exhibit uncontrolled growth and division.
• What is the genetic blueprint of life?

  DNA
• What is the process of gene expression?

  DNA → RNA → Protein
• How is DNA organized in humans?

  DNA is organized into matched pairs of chromosomes called homologous pairs.
• How many chromosomes are in a human somatic cell?

  46 chromosomes
• What are the two types of chromosomes in humans?

  Autosomal chromosomes and sex chromosomes
• Is chromosome 21 an autosomal or sex chromosome?

  Autosomal chromosome
• What is the karyotype of a human somatic cell?

  Two copies of each chromosome, diploid (2n)
• How do you identify homologous chromosomes?

  They are matched pairs that are similar in size, centromere location, and function.
• How many chromosomes are in a human reproductive cell?

  23 chromosomes
• What happens during the S phase of the somatic cell cycle?

  DNA replication occurs, resulting in the duplication of chromosomes.
• What is the significance of the S phase in the cell cycle?

  It is when all chromosomes are copied.
• What is the outcome of DNA synthesis?

  Each new DNA molecule consists of one old and one new strand.
• What is the chromosome count after the S phase?

  The chromosome count does not increase; it remains the same.
• What occurs during mitosis?

  Nuclear material splits, resulting in two identical nuclei.
• What is the goal of the mitotic phase?

  To divide the parent cell's genetic material into two identical daughter cells.
• What is the result of mitosis and cytokinesis in terms of chromosome number?

  Each daughter cell has the same number of chromosomes as the parent cell.
• What are the functions of mitosis?

  • Produce two daughter cells from one parent cell
  • Produce daughter cells that are genetically identical
  • Growth and repair of body tissues
• What happens when cells go rogue?

  They can lead to cancer due to uncontrollable growth and division.
• What are mutations?

  Changes to the nucleotide sequence of DNA.
• What can cause mutations?

  Chemicals, radiation exposure, or viruses.
• What are proto-oncogenes?

  Genes that speed up the cell cycle and promote cell division.
• What happens when proto-oncogenes mutate?

  They become oncogenes and can lead to uncontrolled cell division.
• What are tumor-suppressor genes?

  Genes that code for proteins that repair DNA and regulate the cell cycle.
• What happens when tumor-suppressor genes are mutated?

  They produce abnormal proteins that cannot repair damaged DNA.
• What is the main issue with cancer cells in terms of cell division?

  They divide indefinitely and lose regulation of the cell cycle.
• What is contact inhibition?

  It is the process where normal cells stop dividing when they touch other cells.
• How do cancer cells differ in terms of stickiness?

  Cancer cells have reduced stickiness and do not adhere to each other as well as normal cells.
• Can cancer be inherited?

  Yes, but it is very rare; most cases are due to sporadic mutations.
• What is a carcinogen?

  A substance that induces mutations in DNA.
• What are some examples of carcinogens?

  UV radiation, tobacco, and alcohol.
• Compare mitosis and meiosis.

  Mitosis:

  • Purpose: Growth/repair
  • # of divisions: 1
  • Parent cell: diploid (2n)
  • Daughter cells: 2, each diploid and identical to parent cell
  • Occurs in: somatic cells

  
  

  Meiosis:

  • Purpose: Reproduction
  • # of divisions: 2
  • Parent cell: diploid (2n)
  • Daughter cells: 4, each haploid and unique
  • Occurs in: gonads