SAT Subject Test in Biology

The SAT Subject Test in Biology assesses students' understanding of biological concepts and principles.

Cell Structure and FunctionGenetics and HeredityPhotosynthesis and Cellular Respiration
Evolution and Natural SelectionEcology and EcosystemsHuman Body Systems
Biotechnology in MedicineConservation and Environmental ProtectionGenetic Testing and Personalized Medicine
Time Management and PacingProcess of Elimination
Cell Structure and F...Genetics and Heredit...Photosynthesis and C...Evolution and Natura...Ecology and Ecosyste...Human Body SystemsBiotechnology in Med...Conservation and Env...Genetic Testing and ...Time Management and ...Process of Eliminati...
Basic Concepts

Genetics and Heredity

Understanding Inheritance

Genetics is the study of how traits pass from parents to offspring. Traits are determined by genes, which are segments of DNA.

Mendel's Laws

Gregor Mendel discovered that inheritance follows specific patterns:

  • Law of Segregation: Each parent gives one allele for each gene.
  • Law of Independent Assortment: Genes for different traits are inherited independently.

DNA and Chromosomes

DNA is organized into chromosomes. Humans have 23 pairs of chromosomes, carrying all our genetic information.

Real World Relevance

Genetics explains why you might look like your parents or why some diseases run in families. It also helps in medicine, agriculture, and crime investigations!

Examples

  • Eye color inheritance follows Mendelian genetics.

  • Cystic fibrosis is a genetic disorder caused by a mutation in a single gene.

In a Nutshell

Genetics is about how traits and information are passed from one generation to the next.

Key Terms

Allele
A variant form of a gene.
Dominant
An allele that is expressed if present.
Recessive
An allele that is only expressed if two copies are present.
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Photosynthesis and Cellular Respiration