Characteristics of Life

Biology

You will explore the characteristics of life, or what constitutes a living thing, and separates it from nonliving things.  Depending on the source, there are from six to about 12 major characteristics of living things.   

Write your answers on the webquest answer sheet.

1. Name some things that are alive:

2.  Name some things which are not.  (This can be a little silly, not too silly.)

3.Are viruses alive? (Give me your thoughts about this. It's okay if you don't fully understand yet.)

Go here:

http://www.slideboom.com/presentations/1591842/livingnonlivingdead

4. What is an organism?

5. Name the eight observable characteristics of living things:

a.

b.

c.

d.

e.

f.

g.

h.

6. How many of the 8 characteristics does an organism need to have?

7. How is something considered non-living?

8. How is something considered dead?

Then go here:

http://utahscience.oremjr.alpine.k12.ut.us/sciber00/7th/classify/living/quiz/livingqu.htm

And click on Living or Non-living for each of the objects.  Go back and forth until you have looked at them all.  See if you can list the characteristics of life about each object as you go.

Next you will watch a series of short videos and complete a data table about them.

http://www.exploratorium.edu/imaging_station/gallery.php?Section=Introd…

Characteristics of Life Data Table

What’s Going On?

Defining "life" is a very difficult task, and scientists don’t all agree on a common list of the characteristics of life. Some of the other characteristics that you may discover in your research, and which are often listed in textbooks, include those listed below. Many of these traits are not limited to living things. For example, fire uses energy, grows, and can reproduce, but it is not considered alive in part because it cannot evolve; its traits are necessary, but not sufficient, for life.

NASA scientist Bruce Jakosky, in his book The Search for Life on Other Planets, provides a generally accepted definition of something being “alive” if it

1) utilizes energy from some source to drive chemical reactions,

2) is capable of reproduction, and

3) can undergo evolution. 

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Then review the following characteristics of life (now expanded)  also from

http://www.exploratorium.edu/imaging_station/activities/classroom/chara…

Characteristics of Living Things

• All organisms use energy (metabolism).
• All organisms maintain a stable internal environment (homeostasis).
• All organisms detect and respond to select external stimuli.
• All organisms can engage in movement (which may occur internally, or even at the cellular level).
• All organisms show growth and development; that is, specialization of cells or structures. (Even unicellular organisms show a tiny amount of growth, and single cells repair and use materials from the environment to replace internal structures as needed.)
• All organisms reproduce. (Even if an individual can’t reproduce, its species can.) In addition, an individual’s cells are constantly reproducing themselves.
• All organisms have nucleic acid as the hereditary molecule. (some form of DNA)
• All organisms show adaptation, which occurs at the individual level and is tightly related to homeostasis.
• All organisms are made of one or more cells.
• All organisms exhibit complex organization, grouping molecules together to form cells; at a higher level, cells are organized into tissues, organs, and organ systems.
• All organisms exhibit evolution over time due to mutation and natural selection (which operates at the species level).

The videos and some of the text for this webquest are found here:

http://www.exploratorium.edu/imaging-station/activities/classroom/characteristics/ca_characteristics.php

Link to printable answer sheet:

https://drive.google.com/open?id=0B0X2Hj6oCD4bNmQ1NXJBQjRHdHc&authuser=0