Plant and Animal Physiology Flashcards
how are complex multicellular animals made possible
a stable internal environment of extracellular fluid
cells are specialized to maintain the internal environment of the organism
external functions
transport of nutrients and waste and maintenance of ion concentrations
internal functions
circulation, energy storage, movement, and information processing
what makes up the extracellular fluid
blood plasma and interstitial fluid that bathes each cell
plasma
fluid portion of the blood and is 20% of all extracellular fluid
intracellular fluid
66% of total body water
exchanges molecules with the interstitial fluid
intersitial fluid
remaining 80% of extracellular fluid that bathes the cells of the body
homeostasis
maintencance of stable conditions in an internal environment
physiological systems are controlled by
nervous and endocrine systems
regulation of the internal environment requires
information
endocrine system
a system of hormone-secreting glands, each of which secretes a type
of hormone directly into the bloodstream to regulate the body.
set point
reference point
feedback/feedforward information
what is happening in the system
error signal
any difference between the set point and feedback information
Effectors
effect changes in the internal environment
controlled by regulatory systems
many are the basis for organ systems
analogy for information
speed limit is the set point
speedometer provides feedback
difference between the two is the ERROR SIGNAL
feedforward: seeing a deer on the road and therefore changing the set point by slowing down
driver is the regulatory system by using feedback information to control the brakes and accelerator
regulatory systems
Obtain, integrate, and process information
- Issue commands to controlled systems
- Contain sensors to provide feedback information that is compared to the set point
Sensory information in regulatory systems includes:
negative feedback and posiitve feedback and feed-forward info
negative feedback
Causes effectors to counteract the influence that creates an error
signal
positive feedback
Amplifies a response. Increases deviation from a set poin
feed-forward info
Anticipates internal changes and changes the set point.
Physiological systems are made up of
organs that serve specific functions.
Organs made up of
tissues, which
are then made up of cells.
epithelial tissue
sheets of tightly connected epithelial cells
create boundaries between the
inside and the outside of the body. Some line blood
vessels and hollow organs.
connective tissue
dispersed cells in a secreted
extracellular matrix.
muscle tissue
elongated cells that
generate force and cause movement.
nervous tissue
(neurons &
glial cells for information using action potentials).
epithelial cells
control filtration and transport of
molecules and ions
Thin squamous cells in the lungs move substances across
them.
functions of connective tissues
cartilage, bone, adipose, blood
cartilage
provides structural support
and is flexible—has chondrocytes, cells
that secrete the extracellular matrix
bone
provides support and is hardened
by calcium phosphate deposition in the
matrix–made by osteoblasts
adipose
tissue includes adipose cells
that form and store lipids
blood
consists of blood cells in a very
liquid extracellular matrix; the blood
plasma
extracellular matrix of connective tissues contains
protein fibers: collagen and elastin
collagen
strong and resistant to stretch,
supports skin and connections between
muscles and bones
elastin
can be stretched and then recoils—
found in tissues that stretch (e.g., lungs,
arteries)
types of muscle tissues
skeletal, cardiacm smooth
skeletal
—responsible for locomotion and other
body movements (e.g., breathing,
walking, shivering)
cardiac
—makes up the heart and is responsible
for the heartbeat and blood flow
smooth
involved in movement and generation
of forces in internal organs (e.g., gut,
blood vessels)
wall of the gut contains four types of tissue
epithelial: digestive tract; secrete digestive juices and hormones; absorb nutrients
connective: mucosa that underlines the epithelium
e and c cover abdominal organs and line the abdominal cavity
smooth: move food through the gut
nervous: controls and coordinates contractions of the smooth muscle
