T3: Voice of the Genome

• What are the basic structural units of all living organisms?

  Cells
• How are cells organized in multicellular organisms?

  Cells are organized into tissues, tissues into organs, and organs into organ systems.
• What type of cells are humans made up of?

  Eukaryotic cells
• What is the function of the nucleus in eukaryotic cells?

  The nucleus contains DNA and is involved in regulating gene expression and cell division.
• What surrounds the nucleus of a eukaryotic cell?

  A double membrane called the envelope
• What is chromatin composed of?

  DNA wrapped around histone proteins
• What is the function of the nucleolus?

  It is the site of ribosome production.
• What is the role of the Rough Endoplasmic Reticulum (RER)?

  The RER folds and processes proteins made on the ribosomes.
• What is the structure of the Smooth Endoplasmic Reticulum (SER)?

  A system of membrane-bound sacs
• What does the Golgi Apparatus do?

  It modifies and packages proteins and lipids.
• What are mitochondria primarily responsible for?

  Cellular respiration
• What is the function of centrioles?

  They are involved in cell division.
• What type of ribosomes are found in eukaryotic cells?

  80S ribosomes
• What do lysosomes contain?

  Digestive enzymes
• Where are proteins produced in the cell?

  On the ribosomes
• What happens to proteins produced on the ribosomes on the RER?

  They are folded and processed in the RER.
• How are proteins transported from the RER to the Golgi apparatus?

  In vesicles
• What modification can occur to proteins in the Golgi apparatus?

  Carbohydrates can be added to form glycoproteins.
• What is exocytosis?

  It is the process by which proteins leave the cell.
• What is the cell wall of prokaryotic cells made of?

  Peptidoglycan
• What is the function of the slime capsule in prokaryotic cells?

  It helps the cell retain moisture and adhere to surfaces.
• What are plasmids?

  Circular pieces of DNA
• What is the role of the flagellum in prokaryotic cells?

  It rotates to move the cell.
• What are pili in prokaryotic cells?

  Hair-like structures that attach to other bacterial cells.
• What are mesosomes believed to be involved in?

  They may contain enzymes required for respiration.
• What is the zona pellucida?

  A protective coating around the ovum.
• What is the main purpose of the zona pellucida?

  To prevent polyspermy.
• What type of nucleus does an ovum contain?

  A haploid nucleus
• What do cortical granules do during fertilization?

  They release substances that cause the zona pellucida to harden.
• What is the function of mitochondria in sperm cells?

  To provide energy for the rotation of the flagellum.
• What do acrosomes contain?

  Digestive enzymes that break down the zona pellucida.
• What occurs during the acrosome reaction?

  Enzymes digest the zona pellucida.
• What happens after the sperm head fuses with the egg cell membrane?

  The sperm nucleus enters the egg cell.
• What is the cortical reaction?

  It causes the zona pellucida to harden and prevents polyspermy.
• What is restored when the nuclei of the sperm and egg fuse?

  A full set of chromosomes
• What is a locus in genetics?

  It is the location of a gene on a chromosome.
• What does it mean for alleles to be autosomally linked?

  They are inherited together because they are on the same chromosome.
• How does recombination in meiosis affect linked genes?

  Genes closer together are less likely to be separated during recombination.
• What are sex-linked genes?

  Genes that occur on the X chromosome.
• Why are some genetic disorders more common in men?

  Because men have only one X chromosome, so they need only one copy of the allele to express the disorder.