Biology

Observational studies

study in biology where scientists observe and collect information withour changing or manipulating anything

Quasi Experimentl studies

A study where researchers examine the effects of a change or treatment and subjects are not randomly assigned to groups

Manipulative experiment

When researchers intentionally change one variable and observe how that change ffects something else

Null hypothesis

is a statement that says there is no effect, no difference or no relationship bewteen the things being studied

prediction

Specific result you expect to happen if your hypothesis is correct

independent variable

factor that the researcher changes or manipulates in an experiment to see what effect it has

Dependent variable

Result of what

What is being measured and the result of what has been altered

Standardized variable

Something that researchers keep the same for every group during an experiment

Treatment group

group in an experiment that receives the condition or treatment being tested

Control group

group that does not receive the treatment being tested (comparison group)

Theory

well-supported, testable explanation about a broad pattern in the world that is confirmed/supported by observations, facts, supported hypotheses, and inferences

Fact

Something that has been repeatedly observed and/or confirmed phenomenon

Evolution

Change in heritable traits of a population through time 

• Is a theory

Great chain of being

An old idea that all living and non-living things could be arranged in a fixed hierarchy from lowest to highest. An idea that species were fixed and did not change over time

Lamarck

• Organisms move up a chain via evolution 

• An individual could change over time 

• Individuals develop traits they "need" based on the environment

Ex. Giraffes: early giraffes had shorter necks; because they used and stretched their necks, they become longer through their lifetime and passed it to their offspring

Aristotle

• Species do not change 

• Chain of increasing complexity

(great chain of being) species are fixed and do not change over time

plato

Species do not change, every organism has an ideal, perfect form

Transitional form

An organism that has a combination of characteristics from an ancestral group and a later descendant group

• does not have to be the direct ancestor of a modern species

Vestigial trait

body structure or feature that was useful in an organism's ancestors but has lost most or all of its original function

Homology

Two or more organisms have similar traits because they inherited those traits from an ancestor

Artificial Selection

Humans choose which organisms reproduce based on traits that humans want

Adaptaion

inherited trait that increases an organisms ability to survive and/or reproduce in a particukar environment

Selection

Some individuals survive and reproduce more successfully than others because of differences in their traits

Natural selection

Heritable traits that are better suited to their enviornment tend to survuve and reproduce more

Biological fittness

an organisms ability to survive and reproduce

How can you determine whether something is alive

Evolve 

Made up of cells

Process environment 

Require carbon to create energy 

Reproduce

Linear scientific method

Observation

Question

Hypothesis

Prediction

Experiment/test

analyze

Conclusion

requirements of natural selection

1. Variation in traits

2. Traits are heritible

3. Individuals with certain traits survive and reproduce more than other individuals

How did evolutionary thought change over time

1. plato

2. aristotle

3. Lamarck

4. Darwin and Wallace