Char of Life Review and Intro to Viruses and Bacteria

Characteristics of Life Review and Intro to Viruses and Bacteria

Characteristics of Life Review

• 1) All living things are made up of one or more cells(Therefore they contain DNA or RNA)

• 2) All living things maintain homeostasis

• 3) All living things have a metabolism (Processing energy)

• 4) All living things can reproduce

• 5) All living things grow and develop

• 6) All living things can respond to stimuli

• 7) All livings things can evolve

Characteristics of Life Review Cntd

What is homeostasis?

- Maintaining a regulated balance.

Example: When it is hot outside your body sweats to cool you down. When it is cold your body shivers to help warm you up. This is your body trying to maintain a certain temperature. This is homeostasis.

Multiple Select

Which are characteristics of life?(select all that apply)

• Made up cells

• Ability to reproduce

• Metabolism

• Maintaining Homeostasis

Multiple Select

Which are characteristics of life?(select all that apply)

• Respond to stimuli

• Ability to evolve

• Growth and Development

• Contain organelles

• Have a nucleus

Bacteria

We recently learned about bacteria. Lets see which characteristics of life bacteria have.

Bacteria

• 1) Made up of 1 or more cells - YES

• 2) Maintain homeostasis - YES

• 3) Have a metabolism - YES

• 4) Can reproduce - YES

• 5) Grow and Develop - YES

• 6) Respond to Stimuli - YES

• 7) Can Evolve - YES

Multiple Choice

Would we consider bacteria a living thing?

• Yes

• No

Viruses

Now we are going to look at the basics of viruses.

Virus

Viruses are simple things that contain genetic material(DNA or RNA) surrounded by a protein shell called a capsid. Viruses are much smaller than eukaryotic and prokaryotic cells.

Multiple Choice

Which biomolecule makes up the capsid?

• Carbohydrate

• Protein

• Lipid

• Nucleic Acid

Virus

Often viruses also have Surface Markers(Glycoproteins, Surface Proteins) which are used to attach to host cells.

Multiple Select

Which are another name for surface markers?(Select all that apply)

• Hydrocarbons

• Surface Proteins

• Glycoproteins

• Surface Lipids

Multiple Choice

What are surface markers used for?

• To attach to a host cell

• To look cool

• To metabolize nutrients

• To maintain homeostasis

Viral Envelope

Some viruses also have an envelope surrounding them. This envelope is a piece of cell membrane that was acquired from the host cell it took over.

Multiple Choice

Where does viruses acquire their envelope from?

• They are born with it

• From the host cell

• From metabolizing nutrients

Viruses and Characteristics of Life

• 1) Made up of 1 or more cells - NO

• 2) Maintain homeostasis - NO

• 3) Have a metabolism - NO

• 4) Can reproduce - YES (Not on its own)

• 5) Grow and Develop - NO

• 6) Respond to Stimuli - NO

• 7) Can Evolve - YES

Multiple Choice

Would we consider a virus a living thing?

• Yes

• No

Virus - Is it Alive?

We see that viruses can reproduce with the help of a host cell and they can evolve but do not have the rest of the characteristics of life. Therefore we cannot say that viruses are alive.