Chapter 1 Biology: Study of Life

1. Chapter 1Biology: Study of Life

2. Section 1-1 Properties/Characteristics of living things (LT) 1. Cellular organization - made of 1 or more cells 2. Reproduction - able to reproduce 3. Metabolism - obtain/use energy to run life processes 4. Homeostasis - maintain consistent internal environ 5. Heredity - pass traits to offspring 6. Responsiveness - respond/adjust to environment 7. Growth and development - grow/develop

3. Section 1-1 • Cell Structure/Function: • All LT are made of 1 or more cells • Cell is smallest unit of life, yet complex • Membrane surround/protect all cells • Reproduction: • Organism makes more of its own kind from one generation to the next

4. Section 1-1 • Metabolism: • Sum of all chemical reactions carried out by an organism • Almost all energy used by a LT was originally captured from sunlight • Homeostasis: • Maintain constant internal environment w/in cell • If unable to maintain homeostasis, then organism may become ill and die

5. Section 1-1 • Heredity: • Passing of traits (genes) from parent to offspring • Genes are encoded in DNA deoxyribonucleic acid • Change (∆) in DNA is a mutation and most are harmful, but some may help organism to survive • Evolution: • ∆ in species over a very long period of time • Species are similar organisms that can produce fertile offspring • Natural selection occurs in organisms w/ favorable traits that help them survive/reproduce

6. Section 1-1 • Ecology/Interdependence: • Organisms are dependent on each other and their environment • Ecology studies interactions of organisms w/ one another and w/ nonliving parts of the environment

7. Section 1-2 • Ways Biology is Making Our Life Better • Preserving our environment • Improving food supply • Understanding human genome • Fighting disease

8. Section 1-2 • Preserving our Environment: • Conservation biologists are exploring ways to achieve a balance between people’s growing need for land and the need to preserve the environment. • Improving Food Supply: • Genetic engineering of plants has made some resistant to herbicides, or poisonous to pests, or more nutritious.

9. Section 1-2 • Understanding Human Genome: • Genome is the complete genetic material contained in an individual. Government-funded and private research teams completed sequencing of the human genome on 4/14/2003; ≈30,000 genes

10. Section 1-2 • Fighting Diseases (dz): • AIDS: dz caused by HIV; virus attacks/destroys immune system • Cancer:growth defect in cells; breakdown of mechanism that controls cell ÷ • Biologists are fighting new dz not known in the past (West Nile virus, mad cow dz) • Gene Therapy: replace defective gene w/ normal one. Researchers believe it is possible to use a virus to transfer normal copy of a gene into a cell (Cystic fibrosis CF, Muscular dystrophy MD)

11. Section 1-3 Scientific Process/Method:

12. Section 1-3 Observation: act of noting/perceiving objects/events using the senses TASTE

13. Section 1-3 • Observations Lead to Questions: • Hypothesis: explanation that might be true; statement that can be tested by additional observations or experimentation • Prediction: expected outcome of a test, assuming hypothesis is correct

14. Section 1-3 • Testing the Hypothesis: • Experiment: planned procedure to test hypothesis • Control group : group in experiment that receives no experimental tx; necessary for comparing results of experiment • Independent variable: factor that’s changed in experiment • Dependent variable: variable measured in experiment, its outcome depends on what is done to independent variable.

15. Section 1-3 • Drawing Conclusions: • Once data are collected/analyzed, conclusion is made as to whether data support hypothesis • Theory: set of related hypotheses tested and confirmed many times by many scientists • Theory unites/explains a broad range of observations • Word theory is used by general public means a guess, or lack of certainty, but in science a theory is a well-supported scientific explanation that