Concepts in Biology

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					Concepts in Biology
    Enger Et Al.
Dr. Michael Gillespie
 Doctor of Chiropractic
        Beginner’s Mind
“In the beginner’s mind there are many
possibilities, but in the experts there are
few. If your mind is empty, it is always
ready for anything; it is open to
everything.” – Shunryu Suzuki
Biology is the science that deals with
Science is a process used to solve
problems or develop an understanding
of natural events.
This process is known as the scientific
       Scientific Method
The scientific method is a way of
gaining information (facts) about the
world by forming possible solutions to
Rigorous testing is employed to
determine if the proposed solutions are
Basic Assumptions in Science
There are specific causes for events
observed in the natural world.
The causes for events in nature can be
There are general rules or patterns that
describe what happens in nature.
Basic Assumptions in Science
Repeated events probably have the
same cause.
What one person observes can be
observed by others.
The same fundamental rules apply,
regardless of when or where they
        Cause and Effect
Some events are correlated (happen
Some events have a cause and effect
relationship (an event is a direct result
result of a previous event).
Components of the Scientific
Openness to new information and ideas
Willingness to submit ones ideas to the
scrutiny of others
Observations are made using our
senses or an extension of our senses.
Observations are careful, thoughtful
recognition of an event.
Questioning and Exploration
Optimal questions lend themselves to
Explore other sources of knowledge
relevant to the question.
A hypothesis is a statement that
provides a possible answer to a
question or an explanation for an
observation that can be tested.
  Characteristics of a Good
Account for all relevant information
Predict future events
Use the simplest hypothesis with the
fewest assumptions
“Make everything as simple as possible,
but not simpler.”
    Testing a Hypothesis
A good hypothesis is testable.
It can be either supported or disproved.
If a hypothesis cannot be disproved,
confidence in it increases.
New information can encourage
scientists to reformulate an hypothesis.
    Methods for Testing a
Collect relevant information.
Make additional observations.
Devise an experiment.
An experiment is a re-creation of an
event or occurrence in a manner that
allows the scientist to support or
disprove a hypothesis.
Variables are individual factors that
help determine the outcome of an
   Controlled Experiment
A controlled experiment is one in
which only one variable is present.
Two groups:
  Control group – no manipulation of the
  Experimental group – a group in which
  one variable is manipulated.
Independent variable – is manipulated in
the experiment by the scientist.
Dependent variable – will change as a
result of manipulation of the independent
There should be only one independent
variable in an experiment.
Be careful not to introduce additional
variables into the experiment.
Development of Theories and
If new evidence consistently and
repeatedly supports the original
hypothesis and other related
hypotheses, we begin to see patterns
Scientific theories and laws come into
    Inductive Reasoning
The process of developing general
principles from the examination of
many specific facts is known as
inductive reasoning or induction.
    Deductive Reasoning
The process of using general principles
to predict the specific facts of a
situation is called deductive
reasoning or deduction.
       Scientific Theory
A theory is a widely accepted,
plausible, general statement about
fundamental concepts in science that
explain why things happen.
A theory is a very broad statement ,
which is the result of years of
observation, questioning,
experimentation, and data analysis.
   Theory Vs. Hypothesis
A hypothesis provides a possible
explanation for a specific question;
whereas a theory is a broad concept
that shapes how scientists look at the
world and how they frame their
          Scientific Law
A scientific law is a uniform or
constant fact of nature that describes
what happens in nature.
           Theory Vs. Law
Theory                    Law
Describes why things      Describes what happens
happen                    in nature
Examined repeatedly       Examined repeatedly
Independently verified    Independently verified
Excellent predictors of   Excellent predictors of
how nature behaves        how nature behaves
  Theoretical And Applied
Theoretical science helps us
understand the structure and function
of things in nature.
Applied science has practical value.
It has applications that change the way
we live.
  Science And Nonscience
The difference between a scientist and
a non-scientist is lies in the manner in
which assumptions are tested.
A scientist continually challenges and
tests principles and assumptions to
determine cause and effect
Pseudoscience is a deceptive practice
that uses the appearance or language
of science to convince, confuse, or
mislead people into thinking that
something has scientific validity.
          What Is Life?
Living things have the ability to interact
with their surroundings.
Living things can manipulate energy
and matter.
Energy is the ability to do work.
Matter is anything that has mass and
takes up space.
    Characteristics Of Life
Metabolic processes.
Generative processes.
Responsive processes.
Control processes.
Unique structural organization.
Metabolism is the sum of all the
chemical processes that occur in the
  Catabolism – The breaking down of
  complex chemical substances into simpler
  Anabolism – The building up of complex
  chemical substances from simpler ones.
    Generative Processes
Generative processes are activities
that result in an increase in the size of
an organism (growth) or an increase in
the number of individuals in a
population (reproduction).
Growth is an increase in body size that
results from an increase in the size of
existing cells, the number of cells, or
A tissue can increase in size due to an
increase in the amount of material
between cells (i.e. bone tissue).
Reproduction is the formation of new
cells for tissue growth, repair, or
The formation of new cells for the
production of a new individual organism
(i.e. through fertilization of an ovum by
a sperm cell).
Two Types Of Reproduction
Sexual reproduction – two
individuals each contribute sex cells,
which leads to the creation of a new,
unique organism.
Asexual reproduction – an organism
makes identical copies of itself.
    Responsive Processes
Responsiveness is the body’s ability
to detect and respond to changes in it’s
internal and external environment.
       Control Processes
Control processes are mechanisms
that ensure an organism will carry out
all metabolic activities in the proper
sequence (coordination) and at the
proper rate (regulation).
   Levels Of Coordination
Coordination occurs at the metabolic
level. Chemical reactions are regulated
in the human body by enzymes.
Coordination also occurs at the
organism level.
Motion   of   the whole body.
Motion   of   individual organs.
Motion   of   single cells.
Motion   of   structures inside cells.
Differentiation is a process a cell
undergoes to develop from an
unspecialized to a specialized state.
Each type of cell has a specialized state
and function.
Stem cells divide and give rise to
progeny that undergo differentiation.
Regulation involves altering the rate
of processes.
The process of maintaining a constant
internal environment is called
Unique Structural Organization
 The unique structural organization of
 living things can be seen at the
 molecular, cellular, and organism levels.
 Cells are the fundamental structural
 units of all living things.
 An organism is any living thing that is
 capable of functioning independently.
Levels Of Body Organization
Chemical level
Cellular level
Tissue level
Organ level
System level
        Chemical Level
Atoms – smallest units of matter that
participate in chemical reactions.
Molecules – two or more atoms joined
          Cellular Level
Molecules combine to form cells.
Cells are the basic structural and
functional units of an organism.
Cells are the smallest living units in the
human body.
Cells are made up of organelles.
Tissues are groups of cells and the materials
surrounding them that work together to
perform a particular function.
4 basic tissue types in the human body:
  Epithelial tissue.
  Connective tissue.
  Muscle tissue.
  Nervous tissue.
Organs are composed of two or more
tissues that work together to perform
specific functions.
They usually have recognizable shapes.
          System Level
A system consists of related organs that
have a common function.
Sometimes an organ is part of more
than one system.
There are eleven systems in the human
        Organ Systems
Integumentary   Cardiovascular
Muscular        Respiratory
Skeletal        Digestive
Nervous         Urinary
Endocrine       Reproductive
Lymphatic and
   Integumentary System
Components – skin, hair, nails, sweat
glands, oil glands.
Functions – protects the body; Helps
regulate body temperature; Eliminates
wastes; Makes vitamin D; Detects
sensations such as touch, pain, warmth,
and cold.
      Muscular System
Components – muscles, tendons.
Functions – produces body movements,
such as walking; Stabilizes body
position (posture); Generates heat.
        Skeletal System
Components – bones, joints, associated
Functions – supports and protects the
body; Aids body movements; Houses
cells that produce blood cells; Stores
minerals and lipids.
         Nervous System
Components – brain, spinal cord, nerves,
special sense organs (I.E. Eyes and ear).
Functions – generates action potentials
(nerve impulses) to regulate body activities;
Detects changes in the body’s internal and
external environments, interprets these
changes, and responds causing muscular
contractions or glandular secretions.
       Endocrine System
Components – hormone producing
glands and hormone producing cells.
Functions – regulates body activities by
releasing hormones (chemical
messengers) transported in blood from
an endocrine gland to a target organ.
   Lymphatic and Immune
Components – lymphatic fluid and vessels;
Spleen, thymus, lymph nodes, tonsils.
Functions – returns proteins and fluids to
blood; Carries lipids from gastrointestinal
tract to blood; Includes structures that
generate lymphocytes (protect against
disease-causing organisms).
    Cardiovascular System
Components – blood, heart, and blood
Functions – heart pumps blood through
vessels; Blood carries oxygen and nutrients to
cells and carbon dioxide and wastes away
from cells; Regulates acid-base balance,
temperature, and water content of body
fluids; Components defend against disease.
      Respiratory System
Components – lungs, air passageways such
as the pharynx (throat), larynx (voice box),
trachea (windpipe), and bronchial tubes.
Functions – transfers oxygen from inhaled air
to blood and carbon-dioxide from blood to
exhaled air; Regulates acid-base balance, air
flowing out through vocal cords produces
       Digestive System
Components – mouth, esophagus,
stomach, small and large intestines, and
anus (organs of GI tract); Salivary
glands, liver, gallbladder, pancreas
(accessory organs).
Functions – physical and chemical
breakdown of food; Absorbs nutrients,
eliminates solid wastes.
         Urinary System
Components – kidneys, ureters, urinary
bladder, urethra.
Functions – produces, stores, and eliminates
urine; Eliminates wastes; Regulates volume
and chemical composition of blood; Maintains
acid-base balance; Maintains mineral balance;
Helps regulate production of red blood cells.
   Reproductive Systems
Components – gonads (testes in males,
ovaries in females), associated organs
(uterine tubes, uterus, and vagina in
females and epididymis, ductus
deferens, and penis in males).
Functions – gonads produce gametes
(sperm or oocytes); Gonads release
Further Levels Of Organization
 Population – a group of individual
 organisms of a particular kind.
 Community – populations of different kinds
 of organisms that interact with one another in
 a particular place.
 Ecosystem – communities (groups of
 populations) that interact with the physical
 world in a particular place.
 Biosphere – the worldwide ecosystem.