Unit 1 – Principles of Cell Biology Chapter 1 biology & you Unit 1 – Principles of Cell Biology

Biology & The Themes Biology – study of life Theme 1 – Cellular Structure & Function Cells – the smallest and highly organized unit that can perform all life functions The basic structure of a cell is identical in all organisms Theme 2 – Reproduction Reproduction – a process used for the purpose of increasing the amount of one’s species from one generation to the next The speed of reproduction depends on the species Does speed of reproduction benefit a species?

Biology & The Themes continued Theme 3 – Metabolism Metabolism – the sum of all the chemical reactions completed by an organism. The flow of energy begins with sunlight, transferred to photosynthetic organisms and plants then eaten by organisms such as humans Theme 4 – Homeostasis Homeostasis – the maintaining of a stable, balance within in an organism even with the effect of external conditions Imbalances of homeostasis can cause an organism to become sick or ultimately die Students should provide examples of homeostasis

Biology & The Themes continued Theme 5 - Heredity Heredity – the passing on of traits from parents to offspring Gene – basic unit of heredity (codes of DNA) Mutation – change in DNA of a gene (negative or positive effect)

Biology & The Themes continued Theme 6 – Evolution Evolution – changes in inherited traits over generations Species – a group of genetically similar organisms that produce fertile offspring Natural Selection – organisms with favorable traits are likely to survive and reproduce Theme 7 – Interdependence Ecology – studying the interactions of organisms with one another and with the non-living parts of their environment

Section 2 – Biology in Your World Preserving Our Environment One of the greatest achievements has been to show the benefits of taking care of our environment. Individuals and industries are trying to find ways to reduce waste and conserve nature and energy. Improving Food Supply Genetic engineering of crops – transferring of genes from one type of plant to another type to produce more beneficial crops What types of foods do you know that are genetically modified?

Section 2 - Continued Understanding the Human Genome Genome – a complete genetic set of material contained within an individual Human Genome 3 billion individual units DNA sequenced at 1,000 units/second How can this information be used?

Fighting Diseases AIDS Cancer A fatal disease caused by HIV (Human Immunodeficiency Virus) HIV – a virus that attacks and destroys the human immune system HIV is hard to make a vaccine for because the genetic sequence is altered as it passes from person to person Cancer A growth defect in the cell cycle, a break down or alteration of the mechanism that controls cell division The key to cancer is early detection and targeting of extra copies of proteins in the cells

Fighting Diseases Emerging Diseases Gene Therapy Diseases that are being revived from past incidents due to traveling abroad West Nile Virus – transmitted from mosquitos originating from Africa Mad Cow Disease – caused by eating infected cattle meat Gene Therapy Replacement of a defective gene with a normal version of that gene Disorders that are good candidates for gene therapy: Cystic fibrosis Muscle Dystrophy Hemophilia Cystic fibrosis – thick, sticky mucus clogs passages in the body’s organs Muscle Dystrophy – progressive weakness in muscle mass Hemophilia – lack of blood clotting

Reading Method - TWIQ T – Topic W – Words I – Ideas Q – Questions In the text the topics of each section are written in RED and should be written first. W – Words Vocabulary words – they are bolded I – Ideas The amount of ideas is based on the length of the section – they should be abbreviated and to the point Q – Questions At least two questions that could be asked about the information to test your knowledge

These both need to be written before anything else! Chapter 1 –Themes of Biology 1. Characteristics of Living Organisms Words: This section is created by skimming the section for all the bolded terms! Biology – study of life Ideas: a. Distinguish between living and non-living Life is maintained by reproduction Cells provide necessary life processes This section is created as you read the section fully Questions: 1. How do organisms adapt to their environment? 2. What do all organisms share? This section is created as if you were to quiz a classmate on the section information.

Scientific Processes Observation: act of jotting down the perception of objects or events using any of your senses Example: There are bubbles coming from the reaction between carbon dioxide and limestone David Bradford – Frogs Counting frog populations in Sequoia and Kings Canyon National Parks Observed a large decrease over the years John Harte – Amphibians Tiger salamanders – populations decreasing by 65% in Rockies Processes Insight: Observations are used to find the cause of the problems and provide evidence to support the claims about the problems Design an experiment activity

Stages of Scientific Investigations Collecting Observations The observations need to be clear, precise and specific! John Harte Observations: Animal behavior, reproduction and environmental conditions Asking Questions Curiosity is the foundation of observations Questions link together observations to form theories

Stages of Scientific Investigations Forming Hypotheses & Making Predictions Hypothesis: an explanation or statement that can be tested by experiments or additional observations – can never be 100% true! Prediction: an expected outcome of a test assuming the hypothesis is correct. Confirming Predictions pH: a relative measure of the hydrogen ion concentration within a solution

Confirming Predictions continued Experiment: a planned process to test a hypothesis Control Group: a group in an experiment that has no experimental treatment (all conditions all kept the same) Independent Variable: the factor of the experiment that is changed (x-axis) Dependent Variable: the factor that is measured (or depends on the independent variable) – (y-axis)

Stages of Scientific Investigations Drawing Conclusions Conclusions are based on data and observations – this can either support or reject an hypothesis Conclusions may lead to new hypothesis or different experimental questions Viewing Conclusions in Context Supporting hypotheses is the beginning of experimentation – these hypotheses and conclusions must be viewed with the original problem to see if the data fits Many roads (causes) lead to the same conclusions Look at page 18

Scientific Explanations Explanations do not come from one experiment – it takes many to provide answers Theory: a set of related hypotheses that have been tested and supported more than once. Constructing a Theory An educated guess Careful Observations Experimentation Validated Experiment Additional Observations Drawing Conclusions Supporting/Rejecting Hypotheses