This 41-slide teaching PowerPoint presentation covers 1.D (Origin of Life) in the AP Biology (2015) curriculum. Each slide includes the 'Essential Knowledge' being covered as well as key terms that students should make note of (editable).
Section 1.C includes three sections:
1.D.1 - Origin Models
1.D.2 - Evidence
The presentation itself contains minimal information as it is intended to be used with teacher guidance. There are 'Video' slides throughout which link to relevant and informative YouTube content. The slides are formatted to be visually pleasing and to also print well for handouts or revision.
**This presentation is based on the AP Biology Course Guide and does not follow any textbook
Please see the preview file (first 12 slides) for an idea of the aesthetic and level of detail in the presentation.
As always, please let me know if you have any suggestions for improvements. These are always a work in progress!
The Essential Knowledge covered includes:
1.D.1 - Speciation
There are several hypotheses about the natural origin of life on Earth, each with supporting scientific evidence.
a. Scientific evidence supports the various models.
- 1. Primitive Earth provided inorganic precursors from which organic molecules could have been synthesized due to the presence of available free energy and the absence of a significant quantity of oxygen.
- 2. In turn, these molecules served as monomers or building blocks for the formation of more complex molecules, including amino acids and nucleotides.
- 3. The joining of these monomers produced polymers with the ability to replicate, store and transfer information.
- 4. These complex reaction sets could have occurred in solution (organic soup model) or as reactions on solid reactive surfaces.
- 5. The RNA World hypothesis proposes that RNA could have been the earliest genetic material.
1.D.2 - Evidence
Scientific evidence from many different disciplines supports models of the origin of life.
a. Geological evidence provides support for models of the origin of life on Earth.
- 1. Thee Earth formed approximately 4.6 billion years ago (bya), and the environment was too hostile for life until 3.9 bya, while the earliest fossil evidence for life dates to 3.5 bya. Taken together, this evidence provides a plausible range of dates when the origin of life could have occurred.
- 2. Chemical experiments have shown that it is possible to form complex organic molecules from inorganic molecules in the absence of life.
b. Molecular and genetic evidence from extant and extinct organisms indicates that all organisms on Earth share a common ancestral origin of life.
- 1. Scientific evidence includes molecular building blocks that are common to all life forms.
- 2. Scientific evidence includes a common genetic code.