Transcript 8 characteristics of living things in detail

All things considered to be alive
have what characteristics in
common?
 Make a list of reasons why you think the
following organisms are considered “alive”.
 Team that comes closest wins!!
8 characteristics of living
things
-
Have cells and DNA
Reproduce
Grow and Develop
Use energy
Have a need for materials and energy
Respond to environment
Maintain internal balance
Evolve over time as a species
1. Have cells and DNA
 Unicellular
 Multi-cellular
1. HAVE CELLS AND DNA
 Multi-cellular: cells differentiate from a
single fertilized egg cell, and they just
“know” to become a heart, leg etc.
 Uni-cellular : one celled organism
(amoeba or bacteria)
 Both above have DNA ( the genetic code:
which is why we look like our parents)
2. All living things reproduce
 There are 2 ways in which this can be
done…
Types of reproduction
2. All living things Reproduce
 There are 2 types of reproduction:
 Asexual : 1 parent (budding) - identical
 bacteria
 Sexual: 2 parents
 cats
 people
3. Living things grow and develop
 What is the difference between the 2
words?
Growth and Development
 Bacteria- grow, they just increase in size
 People – develop … they increase in size
and their bodily functions change over
time….until they become an adult
 ex) puberty…
Living things use energy to
grow/develop/reproduce… or just stay alive
 Where do we get energy from?
 Metabolism: combination of chemical
reactions through which an organism
builds up and breaks down materials (will
release energy) as it carries out life
processes
 Fast metabolism- break down
 Slow metabolism – store for later
How obtain energy?
 Plants: From the sun’s energy
“photosynthesis”
 Lion: From eating other organisms
“herbivore, carnivore”
 Mushroom: From the remains of dead
organisms (decomposers)
6. Living things respond to stimuli
 http://www.fotosearch.com/videofootage/time-lapse-flower_2.html
6. Respond to stimulus
 Stimulus- signal to which an organism
responds
 Response- (what they do because of the
signal)
 Internal stimulus- ex.) sugar levels drop?
…then you feel hungry
 External: ex.) flower leans toward the
window in a classroom
Practice Stimulus and Response
 My niece kicked me in the shin and I
screamed
 I slammed the door and the class jumped
 I turned the light on and the mouse ran
under the table
 I placed my hand on the hot stove and I
yanked it back and yelped
7. Maintain internal balance
 External: conditions may vary widely
 But internal…. Should be kept constant..
This is homeostasis
 Ex) temperature 98.6 F, water content, etc
 Ex of how it happens?
 Shivering/sweating
 Thirst/feeling of fullness
Evolve over time …
8. Evolve over time :Evolution
 100,000’s of millions of years…changes
can be dramatic within a species…
 ex) pre-historic horse was the size of a
Barbie doll horse