BIO 325 – MIDTERM 1 NOTES
CHAPTER 1
Chapter 1
An Introduction to the Human Body
Objectives
After completing this chapter, you should be able to
1. define the terms anatomy and physiology.
2. define the following levels of structural organization: chemical, cellular, tissue, organ, system
and organism.
3. identify the 11 systems of the human body, list representative organs of each system, and
describe the major functions of each system.
4. identify the basic life processes of the human body.
5. define the term homeostasis, and explain the effects of stress on homeostasis.
6. describe the components of a feedback system.
7. compare the operation of negative and positive feedback systems.
8. explain the relationship between homeostasis and disease.
9. describe the anatomical position, and compare common and anatomical terms used to
describe various regions of the human body.
10. define the terms describing directions and anatomical planes used in association with the
human body.
11. list, by name and location, the principal body cavities and the organs contained within them.
Keywords and Topics
Make certain that you can define, and use in context, each of the terms listed below, and that you
understand the significance of each of the concepts.
1. Define the terms anatomy and physiology.
A. Anatomy – the science of the body structures and the relationships among them (ana =
up, tomy = cutting)
B. Dissection –the careful cutting apart of body structures to study their relationships
(dis=apart, section=act of cutting)
C. Physiology – the science of body functions – how the body works (physio = nature, logy
= study of)
2. Define the following levels of structural organization: chemical, cellular, tissue, organ, system,
and organism.
A. chemical level
I. atom – smallest unit of matter that participate in chemical reactions
II. molecule – two or more atoms joined together
B. cellular level
I. cell – molecules form cells which are the basic structural and functional units of
an organism that are composed of chemicals
C. tissue level
I. tissue – are groups of cells and the materials surrounding them that work
together to perform a particular function
D. organ level
I. organ –composed of two or more tissues, they have specific functions and
recognizable shapes
, E. system level
I. system – consists of related organs with a common function
F. organismal level
I. organism—all the parts of the human body functioning together
Chemical level (letter)—includes atoms and molecules (two atoms joined together) examples
are C, H, O, N, Ca, S, molecules are DNA or glucose
Cellular level (word)—molecules combine to form cells (smallest living unit of the human
body) examples are muscle cells, nerve cells, epithelial cells
Tissue level (sentence)—are groups of cells and the material around them that work together
to perform a particular function. Examples are epithelial tissue (covers body surfaces, lines
hollow organs and cavities and forms glands), connective tissue (connects, supports, and
protects body organs while distributing blood vessels to other tissues), muscle tissue
(contracts to make body parts move and generates heat), and nervous tissue (carries
information from one part of the body to another through nerve impulses)
Organ level (paragraphs)—different types of tissues are joined together (organs are
structures composed of two or more types of tissues, they have specific functions and
recognizable shapes).
System level (chapters)—consists of related organs with a common function. Sometimes an
organ can be part of more than one system (ex: pancreas is a part of the digestive system and
the endocrine system)
Organismal level (book)—all the parts of the human body functioning together.
3. Identify the 11 systems of the human body, list representative organs of each system, and
describe the major functions of each system.
A. systems:
integumentary—components are skin, hair, nails, sweat and oil glands. Function is
protecting body, help regulate temperature, eliminates some waste, helps make vit d,
detects sensations such as pain, touch, warmth and cold, stores fat and provides
insulation
skeletal—components are bones and joints and cartilages. Function is to support and
protect body, provides surface area for muscles to attach, aids body movements,
houses cells that produce blood cells, stores minerals and lipids.
Muscular—components are skeletal muscle tissue (usually attached to bones). Function
is body movements (ex walking), maintains posture and produces heat
Nervous—components are the brain spinal cord, nerves and special sense organs like
eyes and ears. Function is to generate action potentials to regulate body activates,
detect changes in body’s internal and external environments, interprets changes and
responds by causing muscular contractions or glandular secretions.
Endocrine—components are hormone producing glands (ex pineal gland,
hypothalamus, thyroid gland, pituitary gland, thymus, parathyroid gland, adrenal glands,
pancreas, ovaries and testes, as well as hormoneproducing cells in several other
organs. Functions are to regulate body activities by releasing hormones (chemical
messengers transported in blood from endocrine glad or tissue to target organ.
Cardiovascular—components are blood, heart, and blood vessels. Function that heart
pumps blood through vessels, blood carries O2 and nutrients to cells and CO2 and
wastes away from cells and helps regulate acidbase balance, temperature, and water
, content of body fluids, blood components help defend against disease and repair
damaged blood vessels.
Lymphatic—components are lymphatic fluid and vessels, spleen, thymus, lymph nodes
and tonsils, cells that carry out immune responses (b cells, t cells and others). Function
is to return proteins and fluid to blood, carry lipids from gastrointestinal tract to
blood, contains sites of maturations and proliferations of b cells and t cells that protect
against diseasecausing microbes.
Respiratory—components are lungs and air pathways (ex pharynx <throat>, larynx
<voice box>, trachea <windpipe>, and bronchial tubes leading into and out of lungs.
Function is to transfer oxygen from inhaled air to blood and co2 from blood to exhaled
air, helps regulates acidbase balance of body fluids, air flowing out of lungs though
vocal cords produce sound.
Digestive—components are organs of gastrointestinal tract, a long tube that includes
the moth, pharynx, esophagus, stomach, small and large intestines and anus. It also
includes accessory organs that assist in digestive process such as salivary glands, liver,
gallbladders, and pancreas. Function is to achieve physical and chemical breakdown of
food, absorb nutrients, eliminate solid wastes.
Urinary—Kidneys, ureters, urinary bladder and urethra. Function is to produce, store
and eliminate urine, eliminate wastes and regulate volume and chemical
composition of blood. Also, to help maintain the acidbase balance of body fluids,
maintains body’s mineral balance, helps regulate production of red blood cells.
Reproductive—gonads (testes in males and ovaries in females), associated organs
(uterine tubes/fallopian tubes, uterus, vagina, and mammary glands in females and
epididymis, ductus or vas deferens, seminal vesicles, prostate and penis in males.
Function is for gonads to produce gametes (sperm or oocytes) that unite to form a
new organism. Gonads also release hormones that regulate reproduction and other
body processes. Associated organs transport and store gametes. Mammary glands
produce milk.
Note: Learn the major components and functions for each system.
4. Define the basic life processes of the human body.
A. Metabolism – the sum of all chemical process that occur in the body
I. Catabolism – (catabol= throwing down) the breakdown of complex chemical
substances into simper components (ex splitting proteins in food into amino
acids)
II. Anabolism – (anabol = a raising up) the building up of complex chemical
substances from small simpler components (using amino acids to anabolize
(build) new proteins that make up body structure such as muscles and bones)
B. Responsiveness—is the body’s ability to detect and respond to changes (ex: an
increase in body temperature during fever is a change in the internal environments,
turning your head towards sounds of brakes is response to external environment.
Different cells respond in different ways—nerve cells generate electrical signals (action
potentials), while muscles cells respond by contracting—making body parts move.
C. Movement—includes motion of the whole body, individual organs, single cells and even
tiny structure inside cells. Ex: after you eat fats your gallbladder contracts and releases
bile into the gastrointestinal tract to help digest them. Or when body tissue is damaged
or infected certain white blood cells move the bloodstream into the affected tissue to
, help clean up and repair the area. Inside cells, vesicles move around to carry out their
functions.
D. Growth—is an increase in body size that results from an increase in the size of existing
cells, an increase in number of cells or both. Sometimes increase in tissue size occurs
because of the amount of material between cells ex is growing bones, which has an
accumulation up of mineral deposits between bone cells causing bone to grown in
length and width.
E. Differentiation—is the development of a cell from an unspecialized to a specialized
state. Such as precursor cells, which can divide and give rise to cells that undergo
differentiation, those are known as stem cells. Each type of cell in the body has a
specializes structure or function that differed from that of its precursor cell (ex
red blood cells and some white blood cells all arise from same precursor cells in
red bone marrow. Or fertilized human egg (ovum) develops into an embryo, then
fetus, infant, child, adult.
I. stem cells
F. Reproduction—is either the formation of new cells for tissue growth, repair or
replacements, OR the production of a new individual. The formations of new cells occur
through cell division. The production of a new individual occurs through the fertilization
of an ovum by a sperm cell to forma zygote – followed by repeated cell divisions and the
differentiation of these cells.
G. Autopsy—“seeing with one’s own eyes”
I. Necropsy—is a postmortem examination of the body and dissection of its internal
organs to confirm cause of death. It can uncover diseases, extent of injuries, and
explain how those things contributed to death. Can provide more information
about diseases etc., and reveal conditions that may affect offspring. Helps in
legal ways toocriminal cases and beneficiaries.
5. Define the term homeostasis, and explain the effects of stress on homeostasis.
A. Homeostasis – is the condition of equilibrium in the body’s internal environments due to
the constant interactions of the body’s many regulatory processes. It is dynamic. Each
structure from the cellular level to the system level contributes in some way to keep the
internal environment within normal limits.
B. body fluids – dilute, watery solutions containing dissolved chemicals
I. intracellular fluid (ICF) – fluid within cells (body’s internal environment)
II. extracellular fluid (ECF) – fluid outside body cells
a. interstitial fluid = internal environment (ECF that fills narrow spaces
between cells of tissues)
b. blood plasma (ECF within blood vessels)
c. lymph (ECF within lymphatic vessels)
d. cerebrospinal fluid (ECF in and around the brain and spinal cord)
e. synovial fluid (ECF in joints)
f. aqueous humor (ECF of the eyes)
g. vitreous body (ECF of the eyes)
6. Describe the components of a feedback system.
A. control of homeostasis; nerve impulses and hormones—homeostasis is continually
being disturbed ex heat in summer, lack of o2 on a run (external), blood glucose levels
fall too low when you skip breakfast (internal enviro). Most of the time its mild but can be
CHAPTER 1
Chapter 1
An Introduction to the Human Body
Objectives
After completing this chapter, you should be able to
1. define the terms anatomy and physiology.
2. define the following levels of structural organization: chemical, cellular, tissue, organ, system
and organism.
3. identify the 11 systems of the human body, list representative organs of each system, and
describe the major functions of each system.
4. identify the basic life processes of the human body.
5. define the term homeostasis, and explain the effects of stress on homeostasis.
6. describe the components of a feedback system.
7. compare the operation of negative and positive feedback systems.
8. explain the relationship between homeostasis and disease.
9. describe the anatomical position, and compare common and anatomical terms used to
describe various regions of the human body.
10. define the terms describing directions and anatomical planes used in association with the
human body.
11. list, by name and location, the principal body cavities and the organs contained within them.
Keywords and Topics
Make certain that you can define, and use in context, each of the terms listed below, and that you
understand the significance of each of the concepts.
1. Define the terms anatomy and physiology.
A. Anatomy – the science of the body structures and the relationships among them (ana =
up, tomy = cutting)
B. Dissection –the careful cutting apart of body structures to study their relationships
(dis=apart, section=act of cutting)
C. Physiology – the science of body functions – how the body works (physio = nature, logy
= study of)
2. Define the following levels of structural organization: chemical, cellular, tissue, organ, system,
and organism.
A. chemical level
I. atom – smallest unit of matter that participate in chemical reactions
II. molecule – two or more atoms joined together
B. cellular level
I. cell – molecules form cells which are the basic structural and functional units of
an organism that are composed of chemicals
C. tissue level
I. tissue – are groups of cells and the materials surrounding them that work
together to perform a particular function
D. organ level
I. organ –composed of two or more tissues, they have specific functions and
recognizable shapes
, E. system level
I. system – consists of related organs with a common function
F. organismal level
I. organism—all the parts of the human body functioning together
Chemical level (letter)—includes atoms and molecules (two atoms joined together) examples
are C, H, O, N, Ca, S, molecules are DNA or glucose
Cellular level (word)—molecules combine to form cells (smallest living unit of the human
body) examples are muscle cells, nerve cells, epithelial cells
Tissue level (sentence)—are groups of cells and the material around them that work together
to perform a particular function. Examples are epithelial tissue (covers body surfaces, lines
hollow organs and cavities and forms glands), connective tissue (connects, supports, and
protects body organs while distributing blood vessels to other tissues), muscle tissue
(contracts to make body parts move and generates heat), and nervous tissue (carries
information from one part of the body to another through nerve impulses)
Organ level (paragraphs)—different types of tissues are joined together (organs are
structures composed of two or more types of tissues, they have specific functions and
recognizable shapes).
System level (chapters)—consists of related organs with a common function. Sometimes an
organ can be part of more than one system (ex: pancreas is a part of the digestive system and
the endocrine system)
Organismal level (book)—all the parts of the human body functioning together.
3. Identify the 11 systems of the human body, list representative organs of each system, and
describe the major functions of each system.
A. systems:
integumentary—components are skin, hair, nails, sweat and oil glands. Function is
protecting body, help regulate temperature, eliminates some waste, helps make vit d,
detects sensations such as pain, touch, warmth and cold, stores fat and provides
insulation
skeletal—components are bones and joints and cartilages. Function is to support and
protect body, provides surface area for muscles to attach, aids body movements,
houses cells that produce blood cells, stores minerals and lipids.
Muscular—components are skeletal muscle tissue (usually attached to bones). Function
is body movements (ex walking), maintains posture and produces heat
Nervous—components are the brain spinal cord, nerves and special sense organs like
eyes and ears. Function is to generate action potentials to regulate body activates,
detect changes in body’s internal and external environments, interprets changes and
responds by causing muscular contractions or glandular secretions.
Endocrine—components are hormone producing glands (ex pineal gland,
hypothalamus, thyroid gland, pituitary gland, thymus, parathyroid gland, adrenal glands,
pancreas, ovaries and testes, as well as hormoneproducing cells in several other
organs. Functions are to regulate body activities by releasing hormones (chemical
messengers transported in blood from endocrine glad or tissue to target organ.
Cardiovascular—components are blood, heart, and blood vessels. Function that heart
pumps blood through vessels, blood carries O2 and nutrients to cells and CO2 and
wastes away from cells and helps regulate acidbase balance, temperature, and water
, content of body fluids, blood components help defend against disease and repair
damaged blood vessels.
Lymphatic—components are lymphatic fluid and vessels, spleen, thymus, lymph nodes
and tonsils, cells that carry out immune responses (b cells, t cells and others). Function
is to return proteins and fluid to blood, carry lipids from gastrointestinal tract to
blood, contains sites of maturations and proliferations of b cells and t cells that protect
against diseasecausing microbes.
Respiratory—components are lungs and air pathways (ex pharynx <throat>, larynx
<voice box>, trachea <windpipe>, and bronchial tubes leading into and out of lungs.
Function is to transfer oxygen from inhaled air to blood and co2 from blood to exhaled
air, helps regulates acidbase balance of body fluids, air flowing out of lungs though
vocal cords produce sound.
Digestive—components are organs of gastrointestinal tract, a long tube that includes
the moth, pharynx, esophagus, stomach, small and large intestines and anus. It also
includes accessory organs that assist in digestive process such as salivary glands, liver,
gallbladders, and pancreas. Function is to achieve physical and chemical breakdown of
food, absorb nutrients, eliminate solid wastes.
Urinary—Kidneys, ureters, urinary bladder and urethra. Function is to produce, store
and eliminate urine, eliminate wastes and regulate volume and chemical
composition of blood. Also, to help maintain the acidbase balance of body fluids,
maintains body’s mineral balance, helps regulate production of red blood cells.
Reproductive—gonads (testes in males and ovaries in females), associated organs
(uterine tubes/fallopian tubes, uterus, vagina, and mammary glands in females and
epididymis, ductus or vas deferens, seminal vesicles, prostate and penis in males.
Function is for gonads to produce gametes (sperm or oocytes) that unite to form a
new organism. Gonads also release hormones that regulate reproduction and other
body processes. Associated organs transport and store gametes. Mammary glands
produce milk.
Note: Learn the major components and functions for each system.
4. Define the basic life processes of the human body.
A. Metabolism – the sum of all chemical process that occur in the body
I. Catabolism – (catabol= throwing down) the breakdown of complex chemical
substances into simper components (ex splitting proteins in food into amino
acids)
II. Anabolism – (anabol = a raising up) the building up of complex chemical
substances from small simpler components (using amino acids to anabolize
(build) new proteins that make up body structure such as muscles and bones)
B. Responsiveness—is the body’s ability to detect and respond to changes (ex: an
increase in body temperature during fever is a change in the internal environments,
turning your head towards sounds of brakes is response to external environment.
Different cells respond in different ways—nerve cells generate electrical signals (action
potentials), while muscles cells respond by contracting—making body parts move.
C. Movement—includes motion of the whole body, individual organs, single cells and even
tiny structure inside cells. Ex: after you eat fats your gallbladder contracts and releases
bile into the gastrointestinal tract to help digest them. Or when body tissue is damaged
or infected certain white blood cells move the bloodstream into the affected tissue to
, help clean up and repair the area. Inside cells, vesicles move around to carry out their
functions.
D. Growth—is an increase in body size that results from an increase in the size of existing
cells, an increase in number of cells or both. Sometimes increase in tissue size occurs
because of the amount of material between cells ex is growing bones, which has an
accumulation up of mineral deposits between bone cells causing bone to grown in
length and width.
E. Differentiation—is the development of a cell from an unspecialized to a specialized
state. Such as precursor cells, which can divide and give rise to cells that undergo
differentiation, those are known as stem cells. Each type of cell in the body has a
specializes structure or function that differed from that of its precursor cell (ex
red blood cells and some white blood cells all arise from same precursor cells in
red bone marrow. Or fertilized human egg (ovum) develops into an embryo, then
fetus, infant, child, adult.
I. stem cells
F. Reproduction—is either the formation of new cells for tissue growth, repair or
replacements, OR the production of a new individual. The formations of new cells occur
through cell division. The production of a new individual occurs through the fertilization
of an ovum by a sperm cell to forma zygote – followed by repeated cell divisions and the
differentiation of these cells.
G. Autopsy—“seeing with one’s own eyes”
I. Necropsy—is a postmortem examination of the body and dissection of its internal
organs to confirm cause of death. It can uncover diseases, extent of injuries, and
explain how those things contributed to death. Can provide more information
about diseases etc., and reveal conditions that may affect offspring. Helps in
legal ways toocriminal cases and beneficiaries.
5. Define the term homeostasis, and explain the effects of stress on homeostasis.
A. Homeostasis – is the condition of equilibrium in the body’s internal environments due to
the constant interactions of the body’s many regulatory processes. It is dynamic. Each
structure from the cellular level to the system level contributes in some way to keep the
internal environment within normal limits.
B. body fluids – dilute, watery solutions containing dissolved chemicals
I. intracellular fluid (ICF) – fluid within cells (body’s internal environment)
II. extracellular fluid (ECF) – fluid outside body cells
a. interstitial fluid = internal environment (ECF that fills narrow spaces
between cells of tissues)
b. blood plasma (ECF within blood vessels)
c. lymph (ECF within lymphatic vessels)
d. cerebrospinal fluid (ECF in and around the brain and spinal cord)
e. synovial fluid (ECF in joints)
f. aqueous humor (ECF of the eyes)
g. vitreous body (ECF of the eyes)
6. Describe the components of a feedback system.
A. control of homeostasis; nerve impulses and hormones—homeostasis is continually
being disturbed ex heat in summer, lack of o2 on a run (external), blood glucose levels
fall too low when you skip breakfast (internal enviro). Most of the time its mild but can be
