Slide 2 Biology - the science of life Bio- = life-logy = the
study of There is a lot of living stuff Too many for one person to
be an expert in everything Biology is broken down into many
branches so scientists can specialize Slide 3 Botany the study of
plants Zoology the study of animals Anatomy the study of structures
of living things Physiology the study of the functions of living
things Taxonomy the study of classification of living things
Cytology the study of cells Slide 4 How do you determine if
something is living? Is a crystal garden alive? Is a wooden table
living? Characteristics of Life Video There are seven (7) criteria
that must be met for something to be classified as living Slide 5
1. Cellular Organization All living things must have at least one
cell Cell a highly organized, tiny structure that can perform all
life processes We will study cells more in depth later Slide 6 2.
Homeostasis Homeostasis maintaining a constant internal state in a
changing environment What happens when you go for a run? What do
cold-blooded animals do to keep their body temperature stable? A
stable internal environment is important in order to function
properly Slide 7 3. Metabolism Metabolism the sum of all chemical
processes that occur in an organism Chemical processes are used in
order to obtain energy Almost all energy used by living things
comes from sunlight What do I mean by this?? Obviously humans dont
use photosynthesis Slide 8 4. Responsiveness Responding to the
outside environment Examples: 1. Plants bending toward light 2.
Turning towards a loud, sudden noise 3. Putting on a hat in winter
Slide 9 5. Reproduction Reproduction producing offspring
Essentialbecause nothing lives forever (except vampires) Slide 10
6. Heredity Heredity the passing of genetic information from parent
to offspring Why children tend to look like their parents Inherited
traits change over generations (evolution) More on this later Slide
11 7. Growth Everything grows, even single-celled organisms
Galapagos tortoise: one of the longest lived species in the animal
kingdom Harriet about 170 years old Slide 12 Biologists are working
to solve todays problems, such as: Preserving our environment
Improving the food supply Understanding the human genome Fighting
disease Slide 13 Preserving our environment Expert: conservation
biologists Exploring ways to achieve a balance between peoples
growing need for land and the need to preserve the environment
Slide 14 Improving the food supply Expert: genetic engineer Genetic
engineering of crop plants has made some plants resistant to
herbicides Or poisonous to insect pests Or even more nutritious!
Slide 15 Understanding the human genome Expert: geneticist Genome:
the complete genetic material contained in an individual Only
government program to be finished before the deadline and under
budget!!! Slide 16 Fighting disease Expert: virologist, doctors,
lots of people AIDS fatal disease caused by HIV HIV = human
immunodeficiency virus A virus that attacks and destroys the human
immune system New vaccines are being tested Attack 2 or more parts
of the HIV virus at the same time One part may mutate Unlikely that
both parts will mutate in the same virus particle There is finally
hope of a successful vaccine to control the outbreak of AIDS 2yo
'cured' of HIV 2yo 'cured' of HIV Another one Another one Slide 17
1. Collecting Observations 2. Asking Questions 3. Hypothesizing and
Making Predictions 4. Confirming Predictions 5. Drawing conclusions
Slide 18 Observation the act of noting or perceiving objects or
events using the senses All scientists have a certain way of
investigating the world Scientific investigations begin with
observations Observations cause scientists to ask questions about
their observations Slide 19 Scientific investigations tend to have
common stages These stages are called the Scientific Method There
is more than one way to conduct an investigation Slide 20
Hypothesis An explanation that might be true A statement that can
be tested by additional observations or experimentation Prediction
The expected outcome of a test This assumes that the hypothesis is
correct Slide 21 Experiment A planned procedure to test a
hypothesis Control group A group in an experiment that receives no
experimental treatment Necessary for comparing the results of the
experiment Slide 22 Independent Variable The factor that is changed
in an experiment Dependent Variable The variable that is measured
in an experiment The outcome of the dependent variable depends on
what is done to the independent variable Slide 23 Drawing
Conclusions Once data are collected and analyzed a conclusion is
made Either the data supports the hypothesis or it does not There
is often more than one possible reason for a result All of the
factors that may affect an outcome must be considered Slide 24
Theory A set of related hypotheses that have been tested and
confirmed many times by many scientists A theory unites and
explains a broad range of observations Theory is used by the
general public to mean a guess or lack of certainty Slide 25 In
Science, a theory is a well-supported scientific explanation that
makes useful predictions Slide 26 Section 3.1 Slide 27 Atom
smallest unit of matter that cannot be broken down by chemical
means Consists of: Electrons Protons Neutrons Slide 28 Elements
Element pure substance made of only one kind of atom Elements
differ in the number of protons their atoms contain Slide 29
Chemical Bonding Atoms can join with other atoms to form stable
substances The force that joins atoms is called a chemical bond
Compound substance made of the joined atoms of two or more
different elements Slide 30 Covalent Bonds Form when two or more
atoms share electrons to form a molecule Molecule groups of atoms
held together by covalent bonds Ex) water Slide 31 Covalent bonds
(cont) The arrangement of their electrons determines how atoms bond
together An atom becomes stable when its outer electron level is
full Not full: an atom will react with other atoms that can provide
electrons to fill its outer shell Slide 32 Hydrogen bonds In a
water molecule, the shared electrons are attracted more strongly by
the oxygen nucleus than by the hydrogen nuclei Molecules with
unequal distribution of electrical charge are called polar
molecules Ex) two water molecules Slide 33 Ionic Bonds Ion - when
an atom or molecule has gained or lost one or more electrons Ions
have an electrical charge because they contain an unequal number of
electrons and protons Ions of opposite charge may interact to form
an ionic bond Slide 34 Slide 35 Section 3.2 Slide 36 Many organisms
release excess heat through water evaporation This ability to
control temperature enables cells to maintain a constant internal
temperature when the external temperature changes HOMEOSTASIS!!
Slide 37 Cohesion An attraction between substances of the same kind
Because of this, water and other liquids form thin films and drops
Because water has hydrogen bonds, the attraction between water
molecules causes a condition known as surface tension Slide 38
Adhesion Attraction between different substances Adhesion powers a
process called capillary action Water molecules move upward through
a narrow tube Ex) stem of a plant Slide 39 Solution Mixture in
which one or more substances are evenly distributed in another
substance Slide 40 Polarity The polarity of water enable many
substances to dissolve in water When ionic compounds are dissolved
in water, the ions become surrounded by polar water molecules
Result: a mixture of water molecules and ions Nonpolar molecules do
not dissolve in water well Slide 41 Acids and Bases Compounds that
form hydrogen ions when dissolved in water are called acids When an
acid is added to water, the concentration of hydrogen ions in the
solution is increased above that of pure water Slide 42 Compounds
that reduce the concentration of hydrogen ions in a solution are
called bases Many bases form hydroxide ions when dissolved in water
Slide 43 The pH scale measures the concentration of hydrogen ions
in a solution Slide 44 Section 3.3 Slide 45 Biomolecules parts of a
cell that are made up of large, complex molecules Basic unit:
carbon Can form bonds with as many as four other atoms Four types:
1.Carbohydrates 2.Lipids 3.Proteins 4.Nucleic Acids Slide 46
Carbohydrates Molecules made of sugars made of carbon, hydrogen and
oxygen atoms In the proportion of 1:2:1 Carbohydrates are a key
source of energy Found in most foods (especially fruits,
vegetables, and grains) Slide 47 Common sugar: glucose A
monosaccharide = single sugar Two sugars can be linked to make a
disaccharide = simple carbohydrate Many sugars can be linked to
make a polysaccharide = complex carbohydrate Slide 48 Chitin found
in shells of insects Cellulose found in the cell walls of plants
Carbs are also used as an identifier on the surface of cells Slide
49 Fats, steroids, waxes Long chains of carbon and hydrogen atoms
Main function: storing energy Slide 50 Building blocks are amino
acids Chains of amino acids folded into different shapes Different
shapes = different function Structure Support Movement
Transportation Slide 51 Nucleic acids are chains of nucleotides
Nucleotide molecule made of three parts Sugar Base Phosphate group
Examples: DNA and RNA Slide 52 DNA Act as instructions for the
processes of an organisms life Has two strands of nucleotides that
spiral around each other RNA Interacts with DNA to help decode
information
