Life on Earth

Question 1

How can life be described chemically?

Answer 1

Life is chemical structures that take in and release energy and reproduce

Question 2

Generally, how are life forms different? Similar?

Answer 2

Life forms are very diverse in their physiology, functions, etc. But all share the same building blocks. All life operates in very similar ways. (DNA, transcription/translation, etc.)

Question 3

What are some common characteristics of life?

Answer 3

Growth
* Metabolism
* Response to stimuli
* Movement
* Reproduction

Question 4

What is the smallest unit of life?

Answer 4

Cells

Question 5

How do new cells arise?

Answer 5

From preexisting cells

Question 6

Are the majority of organisms uni- or multicellular?

Answer 6

Unicellular

Question 7

Provide examples of unicellular organisms

Answer 7

Bacteria, archaea, unicellular eukaryotes

Question 8

Give a general overview of how one cell eventually forms an organism.

Answer 8

start as a fertilized egg, continuously divide and replicate, specialize, eventually form an organism.

Question 9

What is the size of most cells?

Answer 9

0.5-20 um. Too small to be seen with naked eye.

Question 10

What is this describing: A lipid-membrane-bound unit filled with a concentrated and
organized aqueous solution containing
- proteins - variety of organic compounds
- nucleic acids - inorganic ions
- carbohydrates - organelles (not all)
- lipids - water

Answer 10

Cells

Question 11

Describe the central dogma.

Answer 11

Central Dogma is the major principal which
allows cells to take control of itself
* Cells contain DNA, which genetic information is
stored on
* Genetic information written on DNA is
expressed to produce a product which is used
to control cellular activity (transcription and
translation)
In short: DNA -> RNA -> protein

Question 12

What is this an image of?

Answer 12

The central dogma