About General Science

The General Science section evaluates your understanding of fundamental scientific concepts across multiple disciplines. This includes life science (biology, ecology, human anatomy), physical science (chemistry, physics), and earth and space science (geology, meteorology, astronomy). On the CAT-ASVAB, you will have 15 scored questions with a 12-minute official subtest limit. While this section does not directly contribute to your AFQT score, it is a critical component of several composite line scores including ST (Skilled Technical), EL (Electronics), and GM (General Maintenance), which determine eligibility for many technical military jobs.

Topics Covered

Human Biology & Anatomy
Cell Biology & Genetics
Ecology & Ecosystems
Chemistry Fundamentals
Physics Basics
Earth Science & Geology
Weather & Meteorology
Astronomy & Space Science
Scientific Method
Nutrition & Health

Sample Questions

Sample Question 1
Which blood type is considered the 'universal donor'?
  • Type A
  • Type B
  • Type AB
  • Type O negative
Type O negative can be given to any blood type because it lacks A, B, and Rh antigens.
Sample Question 2
What is the function of red blood cells?
  • Fight infections
  • Carry oxygen
  • Clot blood
  • Produce antibodies
Red blood cells contain hemoglobin which binds to oxygen and transports it throughout the body.
Sample Question 3
What is the function of chlorophyll in plants?
  • Transport water
  • Absorb light energy for photosynthesis
  • Store food
  • Protect from insects
Chlorophyll absorbs light energy (mainly red and blue) to power photosynthesis.

Study Tips for General Science

Focus on Breadth, Not Depth

The GS section covers many topics at a surface level. Focus on understanding key concepts across all sciences rather than deep-diving into one area.

Use Flashcards for Terminology

Many GS questions test vocabulary and definitions. Create flashcards for scientific terms, especially in biology and chemistry.

Review the Periodic Table Basics

Know the common elements, their symbols, and basic properties. You don't need to memorize the entire table, but understanding groups and periods helps.