CHAPTER 1 THE SCIENCE OF LIFE

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CHAPTER 1THE SCIENCE OF LIFE

• HHS
• Tyska
• HONORS
• BIOLOGY

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Section 1-1Themes of Biology

• The study of ______________________________
• from microscopic single cells to multi-celled
  organisms
• global interactions between organisms
• life history of individual organisms and
  collective history of all organisms

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6 MAJOR THEMES IN THE STUDY OF LIFE

• Cell Structure Function
• Stability Homeostasis
• Reproduction Inheritance
• Evolution
• Interdependence of Organisms
• Matter, Energy Organization

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1 Cell Structure Function
The _____________ is the basic unit of
life. Unicellular vs multicellular
organisms _________________________________
process whereby cells become specialized to
follow the various roles given by their genetic
instructions
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2 Stability Homeostasis

• _______________________ The process by which
  organisms keep internal conditions relatively
  constant despite changes in external environments.

Example of homeostasis control of room
temperature
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3 - Reproduction Inheritance
Organisms transmit hereditary information
(__________) to their offspring.
__________________ REPRODUCTION cells from 2
different parents unite to produce the first cell
of the new organisms ___________________REPRODUCTI
ON a single-celled organism divides in half to
form two new organisms
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CONTINUITY OF LIFE DEPENDS ON HERITABLE
INFORMATION - DNA
____________ short segments of DNA that contains
the instructions for the development of a single
trait Each cell contains all the DNA necessary
for life.
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4 - EVOLUTION
The traits that define a population of organisms
can change over the generations.
__________________________ organisms that have
certain favorable traits are better able to
successfully reproduce than those that lack these
traits the driving force behind evolution
Charles Darwin (18091882) Father of Evolution
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__________________________
Evolutionary adaptation is a product of natural
selection (EX) SEAHORSE
___________________________________ organisms
adapt to different kinds of environments in order
to survive
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5 INTERDEPENDENCE OF ORGANISMS
All organisms need substances such as nutrients,
water and gases from the environment. In
addition, organisms depend on each other for
energy.
__________________ the study of organisms with
one another and with their environment ___________
_______ environmental communities
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6 MATTER, ENERGY, ORGANIZATION
Organisms require ongoing inputs of energy to
maintain their complex organization. _____________
______ plants capture energy from the sun and
convert it into sugars ___________________
organisms that obtain their energy by making
their own food ___________________ organisms
that must take in food to meet their energy needs
energy input, from sun
Producers (plants, and other self-feeding
organisms)
NutrientCycling
Consumers Animals, most fungi, many protists,
many bacteria
energy output (mainly metabolic heat)
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SECTION 1-2Characteristics of Life

• CELLS
• ORGANIZATION All living things are highly
  organized at both molecular cellular levels.
• ENERGY USE All living things have use energy in
  a process called METABOLISM.
• HOMEOSTASIS
• GROWTH The process by which an adult organism
  arises is DEVELOPMENT.
• REPRODUCTION

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SECTION 1-3 SCIENTIFIC METHODS
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Using the SCIENTIFIC METHOD

• ______________________ using the senses to
  gather information about events
• ____________________ form a question based on
  observations
• ______________________ information gathered from
  sampling
• ______________________ interpretation based on
  prior knowledge and experience

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After Observations

• 5) __________________________ proposed
  scientific explanation for a set of observations
• 6)___________________________ statements made in
  advance that states what the results will be
• 7) __________________________ test hypothesis by
  a controlled experiment

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EXPERIMENTATION

• A well-designed experiment must be CONTROLLED
  REPEATABLE
• __________________________ any factor that may
  affect an experiment
• Only ONE VARIABLE must be tested at a time
• A _____________________GROUP is a standard used
  for comparison against one or more
  ______________________ GROUPS

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Setting up a CONTROLLED EXPERIMENT

• VARIABLES
• _______________________Variable single aspect
  of the experiment that is changed
• _______________________Variable measured or
  observed change in response to the manipulated
  variable
• ______________________Variables all parts of
  the experiment that remain unchanged

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Designing an Experiment
Observations/Question
Analyze Results
Form a Hypothesis
Draw a Conclusion
Set Up a Controlled Experiment
Publish Results
Record Results
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Section 1-4 MICROSCOPY MEASUREMENT

• FUNCTIONS
• Microscopes are used for magnifying objects too
  small to see with the human eye.
• They are the most commonly used tool in Biology.
  
• They use light and lenses to increase the size of
  an object.

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Types of Microscopes

• __________________________ light travels through
  thin pieces of a specimens to enlarge it
• ___________________________ used for objects in
  which light can not pass
• ___________________________ a beam of electrons
  produce an enlarged image

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LIGHT MICROSCOPE

• COMPOUND LIGHT MICROSCOPE 2 (or more) sets of
  glass lenses bend waves of light passing through
  the specimen ? forms an enlarged image
• MICROGRAPHS photographs of images from a
  microscope

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Parts of a microscopes

• Eyepiece
• Ocular lens
• Body
• Nosepiece
• Objective lens
• Stage and Clip
• Condenser
• Light source
• Focus- coarse fine

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Ocular lens enlarges primary image formed by
objective lenses.
path of light rays (bottom to top) to eye
Objective lenses (those closest to specimen) form
the primary image. Most compound
light microscopes have several.
prism that directs rays to ocular lens
Stage (holds microscope slide in position)
Condenser lenses focus light rays through
specimen.
illuminator
MICROSCOPE REVIEW
source of illumination (housed in the base of the
microscope)
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Terms

• _________________________ The increase in the
  objects size.
• _________________________ is to factor of
  enlargement calculated by multiplying the
  magnification of the ocular lens x objective
  lens.
• ________________________ The power to show
  detail and clarity.

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ELECTRON MICROSCOPES

• use magnetic lenses to bend beams of electrons ?
  able to resolve details 100,000x smaller than
  light microscopes
• _____________________ internal details (TEM)
• _____________________ image of surface (SEM)

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TRANSMISSION ELECTRON MICROSCOPE
incoming electron beam
condenser lens (focuses a beam of electrons onto
specimen)
specimen
objective lens
intermediate lens
projector lens
viewing screen (or photographic film)
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COMPARING DIFFERENT MICROSCOPES
a Light micrograph (phase-contrast process)
b Light micrograph (Normarski process)
c Transmission electron micrograph, thin section
d Scanning electron micrograph
TEM
SEM
All four images are of green alga at the same
magnification.