Biology Lab Chapter 1

Question 0

Steps of a scientific method

Answer 0

1. Making observations.
2. Formulating a hypothesis
3. Testing the hypothesis.
4. Coming to a conclusion.
5. Developing a scientific theory.

Question 1

Describe the pill bug (armadillidium vulgare) external anatomy and lifestyle.

Answer 1

Outside is “armored” plates that look like little armadillos.
Shed exoskeleton 4-5 times during lifetime.
Can roll into tight ball where legs and head is unseen so called role-poly.
Three body parts: head, thorax and abdomen
Found in: damp leaf litter, under rocks, in basements or crawl spaces under houses.
Inactive in winter. Mate in spring.
Eat dead organic matter like decaying leaves.

Question 2

Distinguish among observations, hypotheses, conclusions, and theories.

Answer 2

Observations - help scientists begin their study of a particular topic.
Hypotheses - based on observations, scientist come to a tentative decision, called a hypothesis. How an experiment will be conducted.
Test hypothesis - perform experiments. Results of the experiment is called data.
Conclusion - whether data support or do not support hypothesis.
Theory - conclusion based on many individual conclusions in the same field.

Question 3

Observe and describe the external anatomy of a pill bug, Armadillidium vulgare.

Answer 3

The head, thorax, abdomens, antennae, eyes, uropods, and one of the seven pairs of legs.

Question 4

Observe and describe how a pill bug move.

Answer 4

Action of feet and other motion
How does it feel crawling in your hand
Ability to move directly forward.
Mouthparts
Anatomical parts that allow a pill bug to identify and take in food.
Pill bug avoid dangerous situations by falling into a ball.
Speed of pill bug.

Question 5

Formulate a hypothesis based on appropriate observations.

Answer 5

Testing whether pill bugs are:

1. attracted to (move toward and eat),
2. repelled by (move away from), or
3. unresponsive to (don’t move away from and do not move toward and eat) the particular foods.
4. If it rolls into a ball, nothing can be concluded.

Question 6

Perform the experiment.

Answer 6

Design an experiment that can be repeated by others.

Keep your pill bug in a Petri dish to test its reaction to the chosen substances. During your experiment, no substance must be put directly on the pillbug, nor can the pillbug be placed directly onto the substances.

Question 7

Come to a conclusion.

Answer 7

Based on observation and experimentation.

Do your results support the hypotheses?
Are there any hypotheses that were not supported by the experimental results (data)?