UP #1: Introduction ot Biology N100
Selected student responses
Q1 = QUESTION 1: What is the difference between a theory
and a belief? You may want to look these terms up before
answering. Be as specific as you can, and give an example of
From JB= A theory is a testable explanation of a broad range of related phenomena, one that has been subjected to extensice experimental testing and can be used with a high degree of confidence, and a belief is something that is trusted or believed. Furthermore a theory is something studied and researched whereas, a belief is more an opinion.
From LE: A theory is something that has been time tested and has held true over rigorous scientific tests. A belief is a view or an opinion someone might hold.
From Jess: The difference between the two is that theories are based on facts and data that are collected, while beliefs are things that people hold to be true without needing actual facts to support them. For example, the Cell Theory is a theory because many scientists through time collected information to support the theory that the cell is the smallest unit of life, and all living organisms are composed of one or more cells. One's belief in God, on the other hand, is a belief because rather than collecting data through time, people believe and have faith that God exists.
Note from Dr. Marrs: Good answers! Theories are explanations based on testable hypothesess - they best explain the available data. Theories cannot be proved, but if enough contrary data is collected, a theory can be discarded in favor of a new theory that better fits the existing evidence. Beliefs are very strong and deeply held feelings, based on internal conviction. There is no need to have facts or data that support beliefs.
QUESTION 2: What characteristic determines whether
organisms belong to the same species? Why are, for instance, are
Rottweilers, bulldogs, and poodles - phenotypically (ie physical
appearance) very different - considered to be members of the same
species dogs (Canis domesticus)? Why are all humans,
despite our numerous phenotypic differences, considered to be one
species (Homo sapiens)?
From SillyPutty Q2 = Reproduction. A rottweiler and a bulldog can mate and reproduce another dog. All humans, unless there are things that prevent this from happening (healthwise), can reproduce and have other humans...,
From Steve Q2 = All dogs are part of the same species because they can all mate with each other and still produce fertile offspring. The fertile offspring is important because some different species can mate, such as a horse and a donkey, and get an infertile offspring, a mule. This is the same with humans, since we can all have children with each even with different skin colors, it means we are the same species.
From Zephyr: Q2 = The way we know that all humans and dogs are of the same species is that they can reproduce and consistantly give birth to viable, fertile offspring.
QUESTION 3: What does the term Survival of the
Fittest mean to you? How does the environment influence the
survival of an organism?
From Dawn: Q3 = Survival of the Fittest doesn't exactly mean- whoever is the strongest will live. I think it means that the ones that are can live in the environment are the most successful. Sometimes the environment changes too quickly for some species to handle, thus they cannot survive and become extinct.
From Big O: Q3 = The term Survival of the Fittest means to me that you ever is the strongest will make it farther than that of someone or something that is weaker. Your surroundings in the environment can help in determining how weak or strong you are.
From Bekah Q3 = To me Survival of the Fittest means there is a natural process that results in the survival and reproductive success of individuals or groups that are best adjusted to their environment. Then, the best group or individuals' best traits flourish and the best of their genetic qualities get passed in to the next generation. The environment has a huge influence on the survival of an organism because the environment determines which organisms survive. I can't see a alligator surviving in the desert.
From Dr. Marrs: Good answers. We will talk about this a lot more when we discuss evolution, but in survival of the fittest, the fittest are those members of a population who are best suited to the environment. It is not necessarily the strongest or the smartest members, but the members that can thrive in their environment that determines which members reproduce and what species and traits will be around in a few generations.