Chapter 1 Biology Science of Life What is
Chapter 1 Biology: Science of Life
What is Science? • A verifiable process – must be testable! • Evidenciary • Collaborative • Constantly questioning the known, the unknown, and each other • Looking for, and trying to solve problems
Overview
Experimental Design recap • Control/ Control group: comparative group; the usual conditions • Experimental group: tested group; alter one condition to compare to control group • Independent variable: altered factor, manipulated variable • Dependent variable: measured factor, responding varibale, data collected • Constant: unchanged factor(s), controlled variables
Analyze and represent data
Biology: Science of Life • Study past, present and future life – Interactions – Structures – Functions • Solve biological problems – Agriculture – Disease – Conservation/Remediation
What is life? We decide: • 1+ cells • Organization • Grow/develop • Reproduce • • Respond to Stimuli Use Energy Homeostasis Adapt/Genetics
Life Traits I • 1+ cells – The cell is the basic unit of life • What does basic unit mean? • Organization – Atoms->molecules->cells->tissues->organ systems>organism (assuming multicellular) • How do we amend this sequence if the organism is unicellular? • Grow/develop – Increase cell size and/or increase cell number – Go through stages of maturity • Homeostasis – Regulate internal conditions Ex: temp, water, blood sugar
• Reproduce Life Traits II – Species = group of organisms that can interbreed to produce viable (fertile) offspring • Respond to Stimuli – Able to process and react to internal/external environ. • Use Energy – Get/make food (chemical energy) to fuel metabolism, get energy (ATP) to power processes • Adapt/Genetics – Change in inherited traits over time
• Cells: Details on Characteristics Unicellular Multicellular 1 st life forms Evolved later 1 cell More than one cell All bacteria, all protists All animals, all plants, (euglena, ameboa, some fungi paramecium), some fungi GROW by cell enlargement only REPRODUCE by cell division (asexual reproduction) GROW by cell enlargement and cell division REPRODUCE mainly by making specialized cells that combine sexually
• REPRODUCTION: Details on Characteristics II Asexual Evolved first Sexual Evolved later Unicellular organisms divide to make more identical unicellulars One “parent” – contributes 100% of genetic info Make a clone – no genetic variation between generations Multicellular organisms use meiosis to make sperm/egg Two “parents” – each contribute 50% of genetic info Genetically different offspring – more variation in population – GOOD for survivability/evolution
More on Reproduction… • Bacteria (unicellular, asexual) can exchange genetic info between individuals to increase genetic variation – Called “conjugation” – Remember: genetic variability is a good thing for evolutionary survival!!
• Adaptation/Response Details on Characteristics III Adaptation (evolution) Response (to stimuli) Long-term Short-term Population response to changing environmental conditions More genetic variability in the population = the better able the population can adapt EX: adaption as a result of changing climate – thicker fur Immediate feedback to stimuli EX: response to changing temperatures – burrow, put on a coat
• Energy use Details on Characteristics III Autotrophs Heterotrophs BOTH versions of organisms convert “food” energy into ATP energy to power their cellular processes!! All plants, some All animals, All fungi, some bacteria, some protists (NOTE: protists some plants can do this too! “carnivorous plants –VFT!) AKA “producers” AKA “consumers” Make own food Eat other organisms or the products of other organisms Two versions: • Photosynthesis • Chemosynthesis
More on Autotrophy… There are two general processes: • Photosynthesis ouse sun as energy needed to make food • Chemosynthesis ouse chemicals as energy o. Hydrothermal deep sea vents
Life vs. Viruses • Bacteria, protists, fungi, plants and animals are living; viruses are NOT • living things have ALL characteristics of life, viruses do not exhibit all • NOTE: anything you need a microscope to see is called a “microbe”, anything that causes disease is called a “pathogen”. – MOST bacteria do not cause human illness!! Viruses: § are acellular § do not (generally) reproduce themselves § do not use energy/ have a metabolism
Chapter 1 The Study of Life 1. 1 Formative Questions What is the process of change that takes place during the life of an organism? A. adaptation B. development C. growth D. maturation 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 1 Formative Questions Some species of plants begin opening their flowers in the morning when they are exposed to sunlight. What characteristic of living things does this represent? A. acquiring energy B. adapting to the environment C. displaying organization D. responding to stimuli 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 1 Formative Questions What process regulates an organism’s internal conditions and keeps them stable? A. adaptation B. equilibrium C. homeostas is D. metabolis m 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 2 Formative Questions What is a theory? A. a body of knowledge about a natural phenomenon B. a creative tool for designing investigations C. a scientific inquiry that seeks to provide an explanation D. an explanation supported by observations and experiments 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 2 Formative Questions Scientists discard observations and data that are not consistent with current scientific understanding. A. true B. false 1. A 2. B
Chapter 1 The Study of Life 1. 2 Formative Questions A scientist wants to report the findings from her investigations. Before her information can be published, what must it go through? A. forensics B. peer review C. scientific methods D. the metric system 1. A 2. B 3. C 4. D
Scientific Theory • Explains natural phenomenon • Supported by observations/experiments • Always same results – Not a hypothesis – Can be modified or discarded by NEW info – Ex. Gravity, cells, tectonic plates
Chapter 1 The Study of Life 1. 3 Formative Questions When you form a logical conclusion based on your observations and what you already know, what are you making? A. a conjecture B. an inference C. a speculation D. a theory 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 3 Formative Questions What is a hypothesis? A. a defined question B. a curious assumption C. a tested inference D. a testable explanation 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life 1. 3 Formative Questions What type of discovery is a serendipitous discovery? A. accidental B. anticipated C. ingenious D. whimsical 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Chapter Diagnostic Questions Why is the metric system preferred by scientists? Answer: Using the same system of measurements allows a scientist to repeat another’s work knowing that he or she is performing the experiments exactly the same.
Chapter 1 The Study of Life Chapter Diagnostic Questions What is a testable explanation? A. observation B. hypothesis C. experiment D. constant 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Chapter Diagnostic Questions Which is not a characteristic of all organisms? A. made of one or more cells B. grows and develops C. capable of rational thought D. maintains homeostasis 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Chapter Assessment Questions Identify the term used to describe an explanation of a natural phenomenon supported by observation and experimentation. A. forensics B. natural law C. theory D. physics 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Chapter Assessment Questions In a controlled experiment, which factor is changed by the experimenter? A. control group B. experimental group C. dependent variable D. independent variable 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Chapter Assessment Questions Look at the figure below. Why is scientific data often displayed in graphs?
Chapter 1 The Study of Life Chapter Assessment Questions Answer: Graphs help show patterns in the data and make it easier to understand.
Chapter 1 The Study of Life Standardized Test Practice Which is the dependent variable in this experiment? A. mass B. number of days 1. A 2. B
Chapter 1 The Study of Life Standardized Test Practice Which biological science was Jane Goodall studying when she observed chimpanzees? A. ecology B. genetics C. animal behavior D. biotechnology 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Standardized Test Practice In which activity would an environmental biologist most likely be involved? A. genetically engineering plants B. finding ways to protect species C. preventing the spread of disease D. developing new medicines and vaccines 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Standardized Test Practice Which is an indication that an idea is based on pseudoscience? A. It brings up more questions. B. It causes disagreement and debate. C. It does not welcome scientific investigation. D. It does not receive acceptance by scientists. 1. A 2. B 3. C 4. D
Chapter 1 The Study of Life Standardized Test Practice Scientists use laboratory rats to test the effects of a new drug, Razatrin. What do rats in the control group receive? A. food containing Razatrin B. food without Razatrin C. food containing another drug D. food containing a variety of drugs E. No food 1. A 2. B 3. C 4. D
- Slides: 38