Biology EOCT Review

1. Biology EOCT Review Milton High School

2. Cell Organelles • Nucleus – holds DNA • Cell membrane – what comes in and goes out • Mitochondria – powerhouse of the cell • Ribosomes – protein synthesis • Lysosomes – digestion • Cell wall – structural support (ex. plants) • Vacuoles – storage • Chloroplasts – in plants for photosynthesis

3. Animal cell vs. Plant cell

4. Differences in Cells Prokaryote Eukaryote Has a nucleus Has membrane-bound organelles Found in plants, animals, fungi, and protists • Lacks nucleus • No membrane-bound organelles • Has a cell wall • Has a cell membrane • Bacteria

5. Viruses • Relies on a host cell to reproduce • Has DNA or RNA

6. Osmosis • How water diffuses into a cell • Diffusion is process which molecules of a substance move from an area of high concentration to an area of low concentration

7. Macromolecules • Carbohydrates – glucose and sucrose • Provide quick energy • Polysaccharides are largest • Lipids – fats, oils, waxes • Insoluble in water • Storage of energy • Proteins – basic building materials • Also contain nitrogen • Made of amino acids (there are 20)

8. Photosynthesis

9. Mitosis vs. Meiosis Mitosis Meiosis FOUR cells are formed Each with half of the number of chromosomes (Haploid number) Forms sex cells (gametes) Requires two cell divisions • Generates TWO identical cells • Maintains chromosome number (Diploid number) • Occurs in body cells (somatic cells)

10. Genetics • Genes are located on chromosomes • Homozygous – both alleles are the same (TT) • Heterozygous – alleles are different (Tt) • Dominant alleles express themselves • Recessive alleles are hidden • Phenotype – physical appearance • Genotype – set of alleles individual receives

12. Some important ecology terms • Community – multiple populations • Abiotic – non-living items in environment • Trophic levels – different levels in food chain • Each level gets energy from level below it • Less energy available as move up to next level • Habitat – where an organism lives • Niche – what an organism does in habitat

13. Less energy available to next level – some energy used for respiration, growth, reproduction.

14. Parasitism – one species benefits and the other species can be harmed (need a host) Tick is an example

15. Commensalism – one species benefits and the other species is neither harmed nor helped The remora and the shark is an example – the remora is a fish which has “suction” disks which allow it to attach to shark without hurting the shark

16. Mutualism – both species benefit A lichen is formed by a relationship between a fungus and a green algae. The fungus anchors the lichen and protects the algae from direct sunlight and extreme temperature fluctuations. The green algae performs photosynthesis, providing food for itself and the fungus.

17. Natural selection - results in the evolution of organisms best adapted to the environment Seed-eating Nectar feeding

18. Acid rain – produced when nitrogen oxide (from car exhaust) or sulfur dioxide (from burning fossil fuels) mixes with rain

19. Enhanced greenhouse effect – more heat trapped – caused by excess carbon dioxide and other greenhouse gases released into the atmosphere