Georgia Performance Standards: Students will understand and identify the characteristics of living organisms.

1
Georgia Performance StandardsStudents will
understand and identify the characteristics of
living organisms.

• Essential Questions
• What are the characteristics of life?

2
1-1 Studying Life

• The word biology means the study of life.
• Biology is the science that seeks to understand
  the living world.
• A biologist is someone who uses a scientific
  method to study living things.

3
Characteristics of Living Things
Characteristic
Examples
Living things are made up of units called cells.
Many microorganisms consist of only a single
cell. Animals and trees are multicellular.
Living things reproduce.
Maple trees reproduce sexually. A hydra can
reproduce asexually by budding.
Living things are based on a universal genetic
code.
Flies produce flies. Dogs produce dogs. Seeds
from maple trees produce maple trees.
Living things grow and develop.
Flies begin life as eggs, then become maggots,
and then become adult flies.
Living things obtain and use materials and energy.
Plants obtain their energy from sunlight.
Animals obtain their energy from the food they
eat.
Leaves and stems of plants grow toward light.
Living things respond to their environment.
Despite changes in the temperature of the
environment, a robin maintains a constant body
temperature.
Living things maintain a stable internal
environment.
Taken as a group, living things change over time.
Plants that live in the desert survive because
they have become adapted to the conditions of the
desert.
4
Cells

• Living things, or organisms, are made up of
  small, self-contained units called cells.
• A cell is a collection of living matter enclosed
  by a barrier that separates the cell from its
  surroundings.

• Cells are the smallest units of an organism that
  can be considered alive.
• grow, respond to their surroundings, and
  reproduce.
• complex and highly organized.
• Unicellular or multicellular

5
Reproduction

•  All organisms produce new organisms through a
  process called reproduction.
• There are two basic kinds of reproduction sexual
  and asexual.
• Many multicellular organisms reproduce sexually.
• In sexual reproduction, two cells from different
  parents unite to produce the first cell of the
  new organism.
• Offspring and parents have different genetic
  info.

• In asexual reproduction, the new organism has a
  single parent.
• Can divided in half to form 2 new organisms
• Can undergo budding where a portion of an
  organism splits off to form a new organism.
• Offspring and parents have identical genetic info.

6
Based on a Genetic Code

• Flies produce flies, dogs produce dogs, and seeds
  from maple trees produce maple trees.
• Biologists now know that the directions for
  inheritance are carried by a molecule called
  deoxyribonucleic acid, or DNA.
• With minor exceptions, the DNA genetic code
  determines the inherited traits of every organism
  on Earth.

7
Growth and Development

•  Each type of organism has a distinctive life
  cyclea particular pattern of growth and change
  that occurs over the organisms lifetime.
• The life cycle (Growth) of many kinds of
  multicellular organisms involves a process called
  development.
• During this process, the cells in an organism not
  only increase in number but also become
  different, or differentiate.

8
Need for Materials and Energy 

• An animal gets the materials and energy it needs
  by eating smaller animals.
• The combination of chemical reactions through
  which an organism builds up or breaks down
  materials as it carries out its life processes is
  called metabolism.
• All organisms take in selected materials that
  they need from their surroundings, or
  environment, but the way they obtain energy
  varies.

9
Maintaining Internal Balance 

• The process by which organisms keep their
  internal conditions relatively stable is called
  homeostasis.
• Homeostasis is constantly being threatened by
  changes in the environment
• changing temperatures and light.

10
Evolution

• A population of any given type of organism can
  evolve, or change over time.
• Over hundreds of thousands or even millions of
  years, the changes in a population can be
  dramatic.
• The ability of a group of organisms to evolve
  over time is extremely important for survival in
  a world that is always changing.

11
Levels of Organization of Life

• Molecules
• Cells
• Organisms
• Populations of a single organism,
• Communities of populations living in the same
  area
• Biosphere.

12
(No Transcript)
13
Checkpoint Questions

• Describe five characteristics of living things.
• What topics might biologists study at the
  community level of organization?
• 3. Compare sexual reproduction and asexual
  reproduction.
• 4. What biological process includes chemical
  reactions that break down materials?
• 5. What happens to an organism if its
  homeostasis is disrupted and not restored?
• 6. Try to think of a nonliving thing that
  satisfies each characteristic of living things.
  Does any nonliving thing have all the
  characteristics of life?

14
Dirty Science Lab

• Your Objective is to see if you can tell by
  looking carefully with a microscope whether
  something in the soil is now alive, is dead but
  once alive, or was never alive.

15
Observing Life

• Crayfish Lab

16
Homework

• Complete Chapter 1 guided reading