Chapter 1 Review

What are the 7 characteristics of life? Metabolism Reproduction Sense and respond to change Change through time (evolution) Homeostasis Organization and cells Growth and development

Define organization. Order within an organism Can be internal or external

List the levels of organization beginning with atoms. Atoms Biological molecules Cellular organelles Cells *** Tissues Organs Organ systems Organism (multicellular)

What is a cell? Is the “stuff” inside of a cell living? Why or why not? Smallest unit that can perform all life processes NO! The cell is the smallest unit of life!

Define stimulus. Change Can be internal or external

Explain what is meant by “response to stimuli.” Organisms can react to changes in their environments

What is homeostasis? Give an example. stability All living organisms have ways to maintain a stable internal environment in changing external conditions Exp. Sweating to maintain body temperature

In the following situation, identify the stimulus and the response. A paramedic shines a pen light into a patient’s eyes. The patient’s pupils get smaller. stimulus = light response = pupils constrict

What is metabolism? The sum of all chemical reactions that take in and transform energy and materials from the environment

What are the two types of metabolism? What’s the difference between the two? Anabolism – building larger products Catabolism – breaking down larger molecules into smaller ones for raw materials

Condensation and hydrolysis: which reaction is anabolic and which is catabolic? Condensation joins small subunits called monomers to form large molecules called polymers so it’s __________! Hydrolysis uses water to break polymers into monomers so it’s ___________! anabolic catabolic

How does growth occur in organisms? Cell division Cell enlargement

Multicellular organisms also develop. What is development? How do organisms develop? Development = process by which organisms become mature adults Cell differentiation – act of cells becoming different from one another Cell specialization – cells perform special and specific jobs

What is reproduction? to produce new organisms essential for survival of the species but not of an individual Important for transmitting hereditary info. encoded in DNA to next generation

Segments of DNA with instructions for a single protein/trait are called _____. Genes!

Differentiate asexual and sexual reproduction. Sexual – Two parents – Offspring are similar to parents but not identical; they’re a combination of both parents’ traits Asexual – One parent – Offspring are genetically identical to parent

What is evolution and how does it occur? Descent with modification i.e. populations change through time Occurs by natural selection – Organisms within a population with more favorable traits are better able to survive and reproduce thus passing those traits on

What are three recurring themes in biology? Unity and diversity of life Interdependences Evolution

What is the scientific method? Organized approach to science

On what two principles is this method based? Events in the natural world have natural causes Uniformity

What is the first step of the scientific method? Observation How are observations made? – All 5 senses Observations lead to _______________ – questions!

The next step is hypothesize. What is a hypothesis? A probably explanation/solution to your question Should it be testable? – Yes! Can we prove a hypothesis? – No! We can only accept (or reject) it.

Once we have a hypothesis we can make a prediction. What’s a prediction? A forecast of what we think will happen if the hypothesis is true.

Scientists will then conduct an experiment. What is a controlled experiment? An experiment that compares groups with only one variable changing between them

List and explain the parts of a controlled experiment. Control = standard group for comparison purposes Experimental groups = identical to control except for one factor or variable Independent variable = manipulated variable Dependent variable = responding variable

Determine the control, experimental groups, the I.V. and the D.V. A shopping mall wanted to determine whether the more expensive “Tough Stuff” floor wax was better then the cheaper “Steel Seal” floor wax at protecting its floor tiles against scratches. One liter of each brand of floor wax was applied to each of 5 test sections of the main hall of the mall. The test sections were all the same size and were covered with the same kind of tiles. Five (5) other test sections received no wax. After 3 weeks, the number of scratches in each of the test sections was counted.

What are two ways scientists can eliminate bias? Blind experiments Repeat experiments

Scientists can collect two types of data. What are they? What’s the difference? Give an example of each. Qualitative descriptions; data is observed not measured colors, textures, smells, tastes, appearances, beauty, etc. Quantitative deals with numbers; data can be measured length, height, area, volume, width, speed, time, temperature, humidity, sound levels, cost, members, ages, etc.

After data collection and analysis, what step comes next? Draw a conclusion/make inferences

The last step is communication. What are some ways scientists communicate research and results? Research teams Joint meetings and symposiums Publish research in journals Peer reviews