Characteristics of Life

Warm Up1. Categorize the following objects as living, nonliving, or dead.• Plant• Paper• Glass of water• Hamburger• Rock• Cut fingernails• Fork• Turtle• Empty turtle shell

2. What are two ways you can tell if something is living, non-living, or dead?

Living Non-living Dead

1.Made of 1 or more cells • All living things are made up of

one or more cells• Unicellular

• Single celled organisms• All bacteria, many protists, and some

fungi

• Multicellular• More than one- usually lots more.• Adult humans 60-90 trillions of cells

• Nonliving matter is acellular• Matter not organized into cells

• Ex) water, minerals, metal, air

• Cell- basic unit of structure and function in all living things

1. Cells • Within one cell is molecules

necessary for carrying out life processes:

• Separation from external environment protects the cell

• Synthesis (building) of molecules

• Breakdown and elimination of waste

• Energy transfers• Replication

• When a cell stops functioning, disease and death can result

2. Displays organization• Molecular organization –

• Molecules are organized into cells and organelles that carry out all processes an organism needs to live.

• Unicellular organisms carry out all life processes inside a single cell

• Organization within the cell is necessary for it functioning

• Multicellular organisms can have higher complexity due to cell specialization

• Groups of cells become specialized for a specific function

• Cell organized into:• Tissues organized into:• Organs organized into:• Organ systems organized into:• Multicellular Organism!

• The whole equals the sum of it parts and if one part fails, all of it fails

3. Requires Energy• Organisms must continually take

in energy in order to grow, reproduce, and maintain homeostasis

• The ultimate source of energy on Earth is the

• Sun!

• Organisms have different mechanisms of energy capture:

• Autotrophs • Solar energy is converted to food

energy in autotrophic cells• Process called photosynthesis

• Heterotrophs• Consume food energy from other

organisms (autotrophs or heterotrophs that have eaten autotrophs)

3. Requires Energy• Both autotrophs and

heterotrophs must convert food energy into cellular energy (ATP)

• Process called cellular respiration• cellular energy powers your

metabolism

• Metabolism = the sum of all the chemical reactions in your body involved in energy transfers

• When energy use is greater than energy input, weakness and death can result

4. Grows and develops• All organism grow

1. Cell growth• One cell increases in size

• How unicellular organisms grow• Too big is not efficient so

microscopic in size

2. Cell division• All life starts as a single cell• Cells divide and make copies of

themselves• More cells = more mass• Cells can specialize to perform

different tasks

4. Grows and develops• Development –

changes in an organism over the course of its lifetime

• Human development ex):

• Zygote embryo baby toddler child adolescent adult

• Development is due to changes in cellular processes

• An organism’s life cycle is marked by developmental changes

5. Reproduces• Asexual reproduction –

• one organism makes a genetic clone of itself

• Ex) one unicellular organism replicates its DNA and then divides into two identical unicellular organisms

• ex) a segment of a multicellular organism breaks off and then forms into a clone of the original

• Sexual reproduction – • requires two organisms. Each contributes

one cell containing half of their genetic information. The two cells fuse and a zygote is formed. The zygote then grows and develops into a unique organism (not clone).

• Without adequate amounts of reproduction each generation, species go extinct.

6. Maintains homeostasis• Homeostasis-

• The process of keeping a stable internal environment necessary for cellular processes even when external conditions are unfavorable

• If anything that happens to an organism that affects it normal state, processes to restore the normal state may begin

• Ex) homeostasis of…• Blood sugar level• Temperature• Water level• pH level• Oxygen level

• Failure to restore homeostasis can result in death

7. Responds to stimuli•Organisms must respond to stimuli appropriately in order to stay alive•Stimulus = anything in an organism’s external or internal environment that causes a reaction or response•Response = a reaction to a stimulus

•Ex) if a shark smells blood in the water, it will respond by moving towards it

7. Responds to stimuli• If I dimmed the lights in here, how would you respond

so you could still process the information on the page?• Pupils would expand

• If I raised the thermostat to 95 degrees, what would your body do so you don’t overheat?

• Sweat, expand blood vessels close to the skin surface

8. Adaptations evolve over generations

• Evolution - Genetic changes in a population ( group of organisms of the same species in the same area) over generations

• Individuals do NOT evolve!• Evolution does NOT occur in a single life time!

• Evolution can be caused by natural selection• Organisms will survive and reproduce more than others based on the traits

they possess. Those beneficial traits will be passed on to their offspring. • Bad traits will be weeded out because organisms that have them will not

survive and reproduce as much. • Given enough time, all organisms in the population will have the beneficial

traits (adaptations) necessary for their environment.

• Failure of a population to adapt to a changing environment may result in the loss of that population

8. Adaptations evolve over generations• Evolution through natural selection leads to adaptations-

• Inherited traits that organisms in populations possess that enable them to thrive in their given environment

• The frogs belonging to African Clawed Frog species all have strongly webbed feet. Why?

Activity• With your group, discuss what characteristic each

picture could represent and provide reasons.

• Conversation stems:• ___________________ is an example of __________________ because

___________________________.• I agree because _________________________. • I disagree because ________________________.• Another option could be ____________________ because

_____________________________.

1. Hummingbird and flower

2. Man shivering

3. Cactus in the desert

4. Streptococcus bacteria

5. Squinting child

6. Bird’s nest

7. Plant

8. Trees in a forest

9. Shark and seal

10. Amoeba and paramecium

Warm upMatter is anything that takes up space. What structure separates living matter from nonliving matter?

A.AtomB.OrganC.CellD.MoleculeE.Brain

Characteristic of Life Video• http://www.youtube.com/watch?v=b2XGl9vv54s

• Watch the student made video to determine the main characteristics of all living things.

Activity- Due today, at the end of the period

• Turn to the person to your right. This will be your partner for this activity.

Story of an Organism

1. Dog 2. Fish

3. Lizard 4. Mushroom

5. Bacteria 6. Tree

Write a story or narrative explaining how this organism came to be classified as a living organism, or explain to someone/ something else how/ why it is considered living. You must use the 8 characteristics of life, from your notes, in your story/ narrative. You must put the number of the characteristic of life in parenthesis (#1-8) to help me locate each of your 8 points. They do not need to be in order.