Multicellular Organisms

• What is the main function of cell division in multicellular organisms?

  To produce new cells
• What does the nucleus contain?

  Chromosomes
• What is the term for the number of chromosomes in a species?

  Chromosome complement
• What does a karyotype show?

  Numbers, appearance, and arrangement of chromosomes
• How many chromosomes do humans have?

  46 chromosomes
• What is a zygote?

  A fertilized egg
• What does diploid mean?

  Double the chromosome number
• What are diploid cells?

  Cells with two matching sets of chromosomes
• What are haploid cells?

  Cells with one set of chromosomes
• Why is maintaining the chromosome complement important during cell division?

  To prevent loss of genetic information
• What is the process of cell division called?

  Mitosis
• What is the purpose of mitosis?

  Growth and repair
• What happens to chromosomes during mitosis?

  They shorten and thicken
• What are chromatids?

  Copies of chromosomes made during mitosis
• Where do chromatids line up during mitosis?

  At the equator of the cell
• What do spindle fibers do during mitosis?

  Attach to the centromere and pull chromatids apart
• What happens after the chromatids are pulled apart?

  Nuclear membrane forms around separated chromosomes
• What is produced at the end of mitosis?

  Two identical daughter cells
• What are the two main purposes of mitosis?

  • Growth
  • Repair
• What are stem cells?

  Unspecialized cells that can develop into many types
• What are the two types of stem cells?

  Adult tissue stem cells and embryonic stem cells
• What can stem cells do?

  Self-renew and differentiate into specialized cells
• What is the function of specialized cells?

  To carry out a particular function
• What are the advantages of using stem cells?

  • Used in medical treatments
  • Useful for research
  • Good supply of stem cells
  • Potential to treat diseases
• What is the function of a red blood cell?

  Carry oxygen
• What is the function of a nerve cell?

  Transfer nerve signals
• What do ciliated cells do?

  Sweep mucus, dust, and bacteria up the throat
• What is the function of a palisade cell?

  Designed for photosynthesis
• What are the levels of organization in multicellular organisms?

  • Cells
  • Tissues
  • Organs
  • Organ Systems
• What are the two systems used for communication in multicellular organisms?

  Nervous and endocrine systems
• How does the nervous system communicate?

  Using electrical impulses
• How does the endocrine system communicate?

  Using hormones
• What does the brain control?

  The whole body
• What is the function of the spinal cord?

  Relay information between nerves and the brain
• What do neurons do?

  Carry electrical impulses to and from muscles and organs
• What is the cerebrum responsible for?

  Conscious thoughts, memory, and emotions
• What does the cerebellum control?

  Balance and coordination of movement
• What does the medulla control?

  Breathing and heart rate
• Where can receptors be found?

  In the eyes, ears, nose, skin, and tongue
• What do receptors detect?

  Stimuli in the environment