Objectives

Every objective will NOT necessarily be covered during class time; you will be independently responsible for some of them.

  1. List reasons why a cell might divide
  2. List the phases of the cell cycle, and the key features of each
  3. Explain the overall process of mitosis, including the number and genetic contents of the cell at the outset and the daughter cells that result
  4. Explain how checkpoints, cyclins, and cyclin-dependent kinases control progress through the cell cycle
  5. Explain how cells can be triggered to or inhibited from dividing based upon both internal and external conditions
  6. Explain how cancer results from disruptions to cell cycle control, including the multi-hit hypothesis
  7. Explain the overall process of meiosis, including the number and genetic contents of the cell at the outset and the daughter cells that result
  8. Explain the typical life cycle in terms of mitosis, meiosis, and fertilization
  9. Explain how meiosis enhances genetic diversity and conserves chromosome count
  10. Compare and contrast mitosis and meiosis
  11. Contrast homologous chromosomes and sister chromatids
  12. Explain why gene distance can be calculated from crossing-over frequency
  13. Calculate gene distance and create gene linkage maps from recombinant offspring data
  14. Give examples of chromosomal disorders due to nondisjunction, including monosomy disorders such as Turner’s Syndrome (XO), and trisomy disorders such as Down’s Syndrome (trisomy 21)
  15. Give examples of other chromosomal abnormalities
  16. Interpret a human karyotype to determine genetic sex and the presence of any chromosomal number abnormalities
  17. Contrast differentiated/specialized cells with undifferentiated/unspecialized/stem cells
  18. Explain how transcription factors, cell-to-cell communication, and tissue-specific proteins can lead to cell differentiation / embryonic induction
  19. Give an example of how events in development are dependent upon both timing and cell location
  20. Interpret transplantation experiment data to draw conclusions about the roles of cells and/or cell regions in development
  21. Define organizer or founder cell, and homeotic gene
  22. Give an example of how micro RNAs play a role in development
  23. Give an example of how apoptosis plays a role in normal differentiation and development

Enduring Understandings

Enduring Understandings are the College Board's AP Biology course concepts that you need to know for the AP exam. Below, you'll find those Enduring Understandings relevant to this unit. Numbering and lettering matches the document linked from the main page of this website.
Every Enduring Understanding will NOT necessarily be covered during class time; you will be independently responsible for some of them.


II.
E. Many biological processes involved in growth, reproduction and dynamic homeostasis include temporal regulation and coordination.
1. Timing and coordination of specific events are necessary for the normal development of an organism, and these events are regulated by a variety of mechanisms.
  • a. Observable cell differentiation results from the expression of genes for tissue-specific proteins.
  • b. Induction of transcription factors during development results in sequential gene expression.
  • c. Homeotic genes are involved in developmental patterns and sequences.
  • d. Embryonic induction in development results in the correct timing of events.
  • f. Genetic mutations can result in abnormal development.
  • g. Genetic transplantation experiments support the link between gene expression and normal development.
  • h. Genetic regulation by microRNAs plays an important role in the development of organisms and the control of cellular functions.
  • i. Programmed cell death (apoptosis) plays a role in the normal development and differentiation.


III.
A. Heritable information provides for continuity of life.
2. In eukaryotes, heritable information is passed to the next generation via processes that include the cell cycle and mitosis or meiosis plus fertilization.
  • a. The cell cycle is a complex set of stages that is highly regulated with checkpoints, which determine the ultimate fate of the cell.
  • b. Interphase consists of three phases: growth, synthesis of DNA, preparation for mitosis.
  • c. The cell cycle is directed by internal controls or checkpoints. Internal and external signals provide stop-and-go signs at the checkpoints.
  • d. Cyclins and cyclin-dependent kinases control the cell cycle.
  • e. Mitosis alternates with interphase in the cell cycle.
  • f. When a cell specializes, it often enters into a stage where it no longer divides, but it can reenter the cell cycle when given appropriate cues. Nondividing cells may exit the cell cycle; or hold at a particular stage in the cell cycle.
  • g. Mitosis passes a complete genome from the parent cell to daughter cells.
  • h. Mitosis occurs after DNA replication.
  • i. Mitosis followed by cytokinesis produces two genetically identical daughter cells.
  • j. Mitosis plays a role in growth, repair, and asexual reproduction.
  • k. Mitosis is a continuous process with observable structural features along the mitotic process. Evidence of student learning is demonstrated by knowing the order of the processes (replication, alignment, separation).
  • l. Meiosis, a reduction division, followed by fertilization ensures genetic diversity in sexually reproducing organisms.
  • m. Meiosis ensures that each gamete receives one complete haploid (1n) set of chromosomes.
  • n. During meiosis, homologous chromosomes are paired, with one homologue originating from the maternal parent and the other from the paternal parent. Orientation of the chromosome pairs is random with respect to the cell poles.
  • o. Separation of the homologous chromosomes ensures that each gamete receives a haploid (1n) set of chromosomes composed of both maternal and paternal chromosomes.
  • p. During meiosis, homologous chromatids exchange genetic material via a process called "crossing over," which increases genetic variation in the resultant gametes.
  • q. Fertilization involves the fusion of two gametes, increases genetic variation in populations by providing for new combinations of genetic information in the zygote, and restores the diploid number of chromosomes.
3. The chromosomal basis of inheritance provides an understanding of the pattern of passage (transmission) of genes from parent to offspring.
  • d. Genes that are adjacent and close to each other on the same chromosome tend to move as a unit; the probability that they will segregate as a unit is a function of the distance between them.


C. The processing of genetic information is imperfect and is a source of genetic variation.
1. Changes in genotype can result in changes in phenotype.
  • a. Alterations in a DNA sequence can lead to changes in the type or amount of the protein produced and the consequent phenotype.
  • e. Changes in chromosome number often result in new phenotypes, including sterility caused by triploidy and increased vigor of other polyploids.
  • f. Changes in chromosome number often result in human disorders with developmental limitations, including Trisomy 21 (Down syndrome) and XO (Turner syndrome).
2. Biological systems have multiple processes that increase genetic variation.
  • c. Sexual reproduction in eukaryotes involving gamete formation, including crossing-over during meiosis and the random assortment of chromosomes during meiosis, and fertilization serve to increase variation. Reproduction processes that increase genetic variation are evolutionarily conserved and are shared by various organisms.


IV.
A. Interactions within biological systems lead to complex properties.
3. Interactions between external stimuli and regulated gene expression result in specialization of cells, tissues and organs.
  • a. Differentiation in development is due to external and internal cues that trigger gene regulation by proteins that bind to DNA.
  • b. Structural and functional divergence of cells in development is due to expression of genes specific to a particular tissue or organ type.


Textbook Reference

This is the part of your textbook that covers the material for this unit.
Ch. 9-10 and Ch 16

Relevant Files

Here, you'll find files for this course. Copies of lecture notes will go here, as will others.





Links

These connect to materials on other teachers' websites that you may find helpful. Generally speaking, I put links to helpful review materials - like video lectures summarizing the material - towards the top, and links to interesting extensions towards the bottom.
Human Health and the Chromosome
Investigating Genetic Disorders
Chromosome Abnormalities Gallery
National Center for Biotechnology Information (professional search databases)
Database of Human Genes
Gene Map of the Human Chromosome
C. elegans Worm Atlas
Mitosis vs Meiosis
Understanding Cancer Series (NIH):
Cell Cycle Control Game
The Genetics of Body Plans
Frog Development
Endless Forms Most Beautiful
Visible Human Project
Visible Human Embryo Project
Stages of Human Embryonic Development
Morphing Embryos
Time Lapse C. elegans Development
Embryo Images - Normal and Abnormal Mammalian Development
UNSW Embryology
How Normal Cells Can Win the Battle for Survival Against Cancer Cells
Apoptosis
The nature of cell-cycle checkpoints: facts and fallacies
cool mitosis computer animation
Mitosis
Meiosis
Silly YouTube Mitosis Video
TedTalk: Alexander Tsiaras: Conception to birth Great footage of a fetus developing.
Meiosis animations
Cell Division animations
Mitosis claymation
TedMed Talk on Mitosis & Cancer with Viewing Questions
Essentials of Cell Biology Unit 5 & Essential of Genetics Unit 2 (Mitosis & Meiosis)
On-Line Onion Root Tips