Homeschool · Diploma track · Grade 9

Biology: The Living Earth: free lessons and course outline

A full year of high school biology for grade 9, built to be the student's whole course in the subject rather than a supplement. California teaches biology as The Living Earth, which means the organism is never studied on its own: every idea is followed out to the ecosystem it sits in and back down to the molecule it runs on. Eleven units take the year from how biological evidence works through ecosystems, cells, DNA, inheritance and evolution to a planet that is measurably changing. Every claim in this course is tied to the evidence for it, because a biology student who can recite a mechanism but cannot say how anyone found it out has learned the wrong thing.

DIPLOMA TRACK CA NGSS LIVING EARTH GRADE 9 MODEL ANSWERS 75 LESSONS 860 PRACTICE QUESTIONS 17 WRITING TASKS AND HOME LABS None. This is a complete course and does not assume other instruction.

California's high school biology course is called The Living Earth, and the name is the syllabus. The state's three-course science model puts biology first, in grade nine, and folds Earth system content into it, so photosynthesis is taught as the thing that built the atmosphere and the carbon cycle is taught as the thing human beings are currently changing. The eleven units follow that logic. The year opens with how biological evidence actually works, because a student who cannot tell a controlled experiment from an anecdote cannot evaluate anything that follows. It then works outside in: ecosystems and the flow of energy, populations, the cycles of matter, then down into the cell, the molecule and the gene, and back out to evolution, speciation and a changing planet. Every performance expectation in HS-LS1 through HS-LS4 is covered, along with the Earth and human sustainability standards California includes in this course. Every lesson ends with ten questions, every unit with a ten-question review, and the year with six pieces of scientific writing that have full model responses.

U1Unit 1: How Biology Knows Things7 lessons
U2Unit 2: Ecosystems, Energy and Trophic Structure7 lessons
U3Unit 3: Populations and Communities7 lessons
U4Unit 4: Matter Cycles and the Earth System6 lessons
U5Unit 5: Cells, Membranes and Transport7 lessons
U6Unit 6: Energy in the Cell7 lessons
U7Unit 7: DNA, Genes and Proteins7 lessons
U8Unit 8: Cell Division, Meiosis and Variation6 lessons
U9Unit 9: Inheritance7 lessons
U10Unit 10: Evolution, Mechanism and Evidence7 lessons
U11Unit 11: Speciation, Biodiversity and a Changing Planet7 lessons

Every lesson, unit by unit

U1 is free to read below. The other units open with a free month or a paid plan.

U1 Unit 1: How Biology Knows ThingsFREE

U2 Unit 2: Ecosystems, Energy and Trophic Structure

2.1 Why life needs constant energy
2.2 Trophic levels and food webs
2.3 The ten percent rule
2.4 Ecological pyramids
2.5 Decomposers and detritus
2.6 Primary productivity
2.7 Energy flows, matter cycles

U3 Unit 3: Populations and Communities

3.1 Measuring a population
3.2 Exponential growth
3.3 Logistic growth and carrying capacity
3.4 Limits on population growth
3.5 Competition and predation
3.6 Symbiosis
3.7 Ecological succession

U4 Unit 4: Matter Cycles and the Earth System

4.1 The water cycle and residence time
4.2 The carbon cycle
4.3 The nitrogen cycle
4.4 Phosphorus and eutrophication
4.5 Feedback loops
4.6 Reading a long atmospheric record

U5 Unit 5: Cells, Membranes and Transport

5.1 Cell theory and its evidence
5.2 Prokaryotic and eukaryotic cells
5.3 Organelles by the job they do
5.4 Surface area to volume in cells
5.5 The cell membrane
5.6 Passive transport and osmosis
5.7 Tonicity and active transport

U6 Unit 6: Energy in the Cell

6.1 ATP, the cell's energy currency
6.2 Enzymes and the active site
6.3 What changes an enzyme's rate
6.4 Photosynthesis: the whole equation
6.5 Light reactions and the Calvin cycle
6.6 Cellular respiration
6.7 Aerobic, anaerobic, and the pair

U7 Unit 7: DNA, Genes and Proteins

7.1 Finding the genetic material
7.2 DNA structure and base pairing
7.3 DNA replication
7.4 Transcription
7.5 Translation and the genetic code
7.6 Mutations
7.7 Gene regulation and differentiation

U8 Unit 8: Cell Division, Meiosis and Variation

8.1 The cell cycle and its checkpoints
8.2 Mitosis
8.3 Meiosis
8.4 Crossing over and assortment
8.5 The sources of variation
8.6 When cell division goes wrong

U9 Unit 9: Inheritance

9.1 Mendel's experiments
9.2 The vocabulary that earns marks
9.3 Monohybrid crosses
9.4 Dihybrid crosses
9.5 Test crosses and pedigrees
9.6 Beyond Mendel
9.7 Sex linkage

U10 Unit 10: Evolution, Mechanism and Evidence

10.1 Darwin's argument in four conditions
10.2 Variation precedes the pressure
10.3 Fitness is reproductive success
10.4 Patterns of selection
10.5 Evidence I: the fossil record
10.6 Evidence II: anatomy and development
10.7 Evidence III: molecules

U11 Unit 11: Speciation, Biodiversity and a Changing Planet

11.1 What a species is
11.2 Reproductive isolation
11.3 Allopatric and sympatric speciation
11.4 Drift, bottlenecks and founders
11.5 Reading a phylogenetic tree
11.6 Biodiversity
11.7 Extinction and a changing climate

Keep going in the full Biology: The Living Earth course

All of U1 (Unit 1: How Biology Knows Things) is free to everyone, with no account. The course has 75 lessons, each with worked examples and practice problems that come with full solutions. A free account can also start a free month of the whole course, with no card.

Open this lesson in the course See the whole course