Ontario Grade 11 SBI3U Biology (Grade 11, University Preparation)
Chapters: 6
1. A. Scientific Investigation Skills and Career Exploration
A1 Scientific Investigation Skills · A2 Career Exploration
- The Scientific Method – The scientific method is the careful way scientists find out how the world works. Observe something, ask a testable question, make a hypothesis (a clear, testable guess), test it with a fair experiment (change one variable, measure one, keep the rest the same), repeat and record data, analyse it, draw a conclusion and share it so others can check. Results that fail the test are useful too: they send you back to a new hypothesis.
2. B. Diversity of Living Things
B1 Relating Science to Technology, Society, and the Environment · B2 Developing Skills of Investigation and Communication · B3 Understanding Basic Concepts
- Biological Classification – Whittaker (1969) sorted living things into five kingdoms, Monera, Protista, Fungi, Plantae and Animalia, using cell type, cell wall, body plan, mode of nutrition, reproduction and relationships. Monera are prokaryotes (bacteria, archaebacteria, cyanobacteria, mycoplasma). Protista are one-celled eukaryotes in five groups. Fungi are heterotrophs with chitin walls in four classes. Lichens are an alga and a fungus living together. Viruses, viroids and prions are not placed in any kingdom.
3. C. Evolution
C1 Relating Science to Technology, Society, and the Environment · C2 Developing Skills of Investigation and Communication · C3 Understanding Basic Concepts
- Evolution: How New Kinds of Living Things Arise – Variations arise during reproduction. Nature selects those that help survival, so over many generations populations change: this is evolution. Only inherited (DNA) changes pass on; acquired changes do not. Separated populations can become new species. Homologous organs, analogous organs and fossils help us trace who is related to whom, and complex organs evolved step by step.
4. D. Genetic Processes
D1 Relating Science to Technology, Society, and the Environment · D2 Developing Skills of Investigation and Communication · D3 Understanding Basic Concepts
- Principles of Inheritance and Variation – Genes come in pairs (alleles). Each parent passes one allele of each pair to the child. Mendel showed dominance (3 : 1), segregation and independent assortment (9 : 3 : 3 : 1). Real life has twists: incomplete dominance (1 : 2 : 1), co-dominance (AB blood), multiple alleles, pleiotropy (one gene, many effects) and polygenic traits (many genes, one trait). Genes sit on chromosomes, so genes on the same chromosome are linked and are separated only by crossing over. Sex chromosomes decide sex (XX-XY in humans, ZW in birds, haplo-diploid in honeybees) and carry sex-linked genes (haemophilia, colour blindness). Mistakes in genes cause Mendelian disorders (thalassemia, sickle-cell) and mistakes in chromosome number cause Down, Turner and Klinefelter syndromes.
5. E. Animals: Structure and Function
E1 Relating Science to Technology, Society, and the Environment · E2 Developing Skills of Investigation and Communication · E3 Understanding Basic Concepts
- Human Body Systems – Your body is organised in levels: cells make tissues, tissues make organs, organs make organ systems, and all systems together make you, the organism. Each system has a main job: skeletal (frame), muscular (movement), circulatory (transport), respiratory (gas exchange), digestive (food), excretory (waste), nervous and endocrine (control), immune (defence), integumentary (skin, hair, nails) and reproductive. No system works alone: during exercise the muscles, heart, lungs and nerves all change together to keep the inside of the body steady (homeostasis).
6. F. Plants: Anatomy, Growth, and Function
F1 Relating Science to Technology, Society, and the Environment · F2 Developing Skills of Investigation and Communication · F3 Understanding Basic Concepts
- Anatomy of Flowering Plants – Anatomy is the study of the inside structure of a plant, seen by cutting thin slices (sections). Plant cells form tissues, and tissues form three tissue systems: epidermal (the skin), ground (the filling) and vascular (xylem and phloem pipes). Dicots and monocots differ in how these systems are arranged in their root, stem and leaf.