About This Chapter
PSSA - Science Grade 8: Genetics & Inherited Traits - Chapter Summary
The lessons in this chapter aid students in studying for the PSSA - Science Grade 8 exam by reviewing important information about genetics and heredity. Students will refresh their understanding of the properties of genes and how genes are passed from one generation to the next. This chapter covers:
- Characteristics of alleles
- Definition and application of Mendel's Law of Segregation and Law of Independent Assortment
- Codominance and incomplete dominance
- Sex linked and sex limited traits
- Polygenic traits
Since we strive to keep the educational experience efficient and enjoyable, students will find several methods for learning. Each lesson contains an engaging video that helps visually depict the material being reviewed. Video transcripts are included as a great resource for taking notes. Students can take a self-assessment quiz after each lesson to gauge their knowledge of the topics. To return to particular section of the lesson, the timeline below the video can be used for easy navigation.
1. Genetics: Heredity, Traits & Chromosomes
We view manipulation of genes in our crops and livestock as a recent development. Yet, man has been manipulating the genetic makeup of his food for thousands of years through cultivation and breeding. This lesson will begin to help you understand how genetics works.
2. Properties of Alleles
What is a dominant phenotype and how will it affect Adrian's flying hamster research? Tune in as he studies homozygous and heterozygous genotypes and the phenotypes they produce.
3. Mendel's First Law: The Law of Segregation
Breaking up is a hard thing to do, but homologous chromosomes always go their separate way. What effect does chromosome segregation have on genetics? We look once more to Adrian's flying hamsters for answers.
4. Application of Mendel's First Law
Hollywood Squares? No, it's Punnett Squares! Those wacky diagrams are a geneticist's best friend. See how they turn geneticists into soothsayers, predicting the genotypic and phenotypic future.
5. Mendel's Second Law: The Law of Independent Assortment
Understanding how Mendel's law of independent assortment describes inheritance of genes is as easy as flipping a coin. Grab a few coins, cue up the video and see how.
6. Mendel's Dihybrid Cross Example: Practice & Ratio
Oh no! Twice the genes and sixteen genotypes - a dihybrid cross seems overwhelming to understand. Never fear though, Punnett squares will save the day!
7. Exceptions to Simple Dominance: Codominance and Incomplete Dominance
Have you ever wondered what it means if someone is a universal donor or acceptor of blood? See how genetic interactions play a key role in this trait.
8. Exceptions to Independent Assortment: Sex-Linked and Sex-Limited Traits
More men are color blind compared women. But often, not every brother, cousin or uncle in a family tree is color blind. Why not? How can genetics explain this seemingly complex inheritance pattern?
9. Polygenic Traits: Definition & Examples
If variety is the spice of life, polygenic inheritance is one genetic mechanism giving us a continuous range of possibilities. In this lesson, learn how a polygenic trait, like height, can be controlled by multiple genes.
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Other chapters within the PSSA - Science Grade 8: Test Prep & Practice course
- PSSA - Science Grade 8: Research & Experiments
- PSSA - Science Grade 8: Scientific Inquiry
- PSSA - Science Grade 8: Environmental Issues
- PSSA - Science Grade 8: History, Nature & Relationships of Science
- PSSA - Science Grade 8: Interpreting Data
- PSSA - Science Grade 8: Evaluating Change in a System
- PSSA - Science Grade 8: Scientific Instruments
- PSSA - Science Grade 8: Systems, Models & Patterns
- PSSA - Science Grade 8: Structure & Function of Living Things
- PSSA - Science Grade 8: Organism Characteristics & Biological Evolution
- PSSA - Science Grade 8: Natural Selection & Evolution
- PSSA - Science Grade 8: Biomes
- PSSA - Science Grade 8: Ecological Systems
- PSSA - Science Grade 8: Human Impact on the Environment
- PSSA - Science Grade 8: Renewable & Non-Renewable Resources
- PSSA - Science Grade 8: Solutions & Elements
- PSSA - Science Grade 8: Matter
- Overview of Stoichiometry
- Types of Reactions in Chemistry
- PSSA - Science Grade 8: Earth's Energy Resources
- PSSA - Science Grade 8: Transfer & Conversion of Energy
- PSSA - Science Grade 8: Solar Radiation & Energy
- PSSA - Science Grade 8: Motion
- PSSA - Science Grade 8: Force
- PSSA - Science Grade 8: Analyzing Forces & Motion
- PSSA - Science Grade 8: Earthquakes, Rocks & Earth
- PSSA - Science Grade 8: Weathering & Erosion
- PSSA - Science Grade 8: The Water Cycle
- PSSA - Science Grade 8: Water Systems on Earth
- Ground Water Systems
- Running Bodies of Water
- Weather Events
- Geomorphology of Arid Regions
- PSSA - Science Grade 8: Atmospheric, Weather & Wind Patterns
- Global Temperature Patterns & The Atmosphere
- PSSA - Science Grade 8: Climate & Climate Change
- Atmospheric Pressure and Wind
- PSSA - Science Grade 8: Clouds
- PSSA - Science Grade 8: Earth, Moon & Sun
- PSSA - Science Grade 8: The Moon
- PSSA - Science Grade 8: Orbits of Celestial Bodies
- PSSA - Science Grade 8 Flashcards