chapter 1 Flashcards
homeostasis
the maintenance of a relatively
constant internal environment despite fluctuations in the external
environment.
Anatomy
the scientific discipline that investigates the
structure of the body—for example, the parts and chambers of the heart.
The word anatomy means
to dissect, or cut apart and separate, the parts of the
body for study.
anatomy examines the relationship between
the
structure of a body part and its function.
two basic approaches to the study of anatomy
Systemic and regional anatomy
Systemic anatomy
the study of the body by systems, such as the cardiovascular, nervous, skeletal, and muscular
systems. It is the approach taken in this textbook.
Regional anatomy
the study of the organization of the body by areas.
two general ways to examine the internal structures of a living person
surface anatomy and anatomical imaging
Surface anatomy
the study of external features, such as bony projections, which serve as landmarks for locating deeper structures.
Anatomical imaging
involves the use of x-rays, ultrasound,
magnetic resonance imaging (MRI), and other technologies to create pictures
of internal structures, such as when determining if a bone is broken or a
ligament is torn.
Both surface anatomy and anatomical imaging provide
important information for diagnosing disease
Physiology (study of nature)
the scientific discipline that deals with the processes or functions of living things.
it is important in physiology to recognize structures as
dynamic
There are two major goals when studying physiology
examining the body’s responses to stimuli and examining the body’s maintenance of stable internal conditions.
Human physiology
study of humans
cellular physiology
focuses on processes inside cells such as the manufacturing of
substances, including proteins.
systemic physiology
focuses on the functions of organ systems.
What are the 6 levels of organization in the body
chemical, cell, tissue, organ, organ system, and organism
Chemical level (simple ver)
atoms combine to form molecules
cell level (simple ver)
molecules form organelles, such as mitochondria and nucleus, which make up cell.
tissue level (simple ver)
similar cells and surrounding materials make up tissue.
organ level (simple ver)
different tissue combines to form organs
organ system (simple ver)
organs make up organ system
organism
organ systems make up an organism
Levels of Organization for the Human Body
The simplest level of organization in the human body is the atom. Atoms combine to form
molecules. Molecules aggregate into cells. Cells form tissues, which combine with other tissues to form organs. Organs work in groups called organ systems. All organ systems work together to form an organism.
Chemical Level
The structural and functional characteristics of all organisms are determined by their chemical makeup.
The chemical level of organization involves how atoms,
such as hydrogen and carbon, interact and combine into molecules.
This is important because
a molecule’s structure determines its function.
collagen molecules are strong, ropelike fibers that give skin structural strength and flexibility.
With aging, the structure of collagen changes, and the skin becomes fragile and more easily torn during everyday activities.
Cell Level
Cells are the basic structural and functional units of organisms, such as plants and animals.
Most cells contain smaller structures inside them, called
Organelles
Organelles carry out particular functions
such as digestion and movement, for the cell.
the nucleus
contains the cell’s hereditary information
mitochondria
manufacture adenosine triphosphate (ATP)
ATP
a molecule cells use for a source of energy.
Although cell types differ in their
structure and function, they have many characteristics in common.
Microbes in your body
more microbial cells than human cells in your body
every cell in your body
there is one microbial cell
40 trillion microbial cells,
which collectively can account for 2 to 6 pounds of your body weight.
A microbe is
any life form that can only be seen with a microscope (for example, bacteria, fungi, and protozoa).
All living organisms fit into one of three domains of living organisms:
(1) Bacteria, (2) Archaea, and (3) Eukarya.
Bacterial cells’ genetic material
is not separated from the rest of the cell by a barrier.
bacterial cells have
far fewer separate structures made of membrane for carrying out the cell’s metabolic processes than eukaryotic cells.
Archaea cells are constructed
similarly to
bacteria; however, they share certain structures, called ribosomes, with eukaryotic cells.
the term prokaryotic is used to describe
bacterial and archaea cells.
Eukarya cells
which include human cells, have the most structural complexity with many smaller structures, called organelles, surrounded by membranes.
These smaller structures conduct
the metabolic processes of the cell.
size differences between bacteria and archaea and cells of eukaryotes is quite evident
with most eukaryotic cells being significantly larger than most prokaryotic cells.
The total population of microbial cells on the human body is
microbiota
the collection of all the microbial cell genes is known as
the microbiome
The microbiota includes
so-called good bacteria, which do not cause disease and may even help us.
pathogenic,
or bad bacteria
What did scientists learn from the Human Microbiome Project?
Human health is dependent upon the health of our microbiota, especially the “good” bacteria.
the human microbiome is intimately involved
in the development and maintenance of the immune system.
more evidence is mounting for a correlation between
a host’s microbiota, digestion, and metabolism.
microbial genes are
more responsible for our survival than human genes are.
There are even a few consistent pathogens that are present without causing disease,
suggesting that their presence may be good for us. However, there does not seem to be a universal healthy human microbiome.
Instead of being a detriment, this variation may actually be very useful
for predicting disease. There seems to be a correlation between autoimmune and inflammatory diseases (Crohn’s disease, asthma, multiple sclerosis), which have become more prevalent, and a “characteristic microbiome community.”
Tissue level
A tissue is a group of similar cells and the materials surrounding
them.
The characteristics of the cells and surrounding materials determine
the functions of the tissue.
The many tissues that make up the body are classified into four primary types:
(1) epithelial, (2) connective, (3) muscle, and (4) nervous.
Organ level
An organ (OR-gan; a tool) is composed of two or more tissue types that together perform one or more common functions.