Chapter 1 Homeostasis
What would result from taking a drug that inhibits the activity of Enzyme C?
1. The concentration of active product would decrease 2. the concentration of intermediate 1 would increase 3. the activity of Enzyme A would increase 4. The concentration of intermediate 2 would increase
Percentage of water in interstitial fluid
25%
There are _______ general categories of differentiated tissue in the body.
4 (muscle, nervous, epithelial, and connective)
Percentage of water in intracellular fluid
67%
Percentage of water in Plasma
7%
Which of the following situations best represents a homeostatic mechanism?
After eating a large batch of salty popcorn, levels of salt in the urine increase
Example of positive feedback loop.
Oxycontin secretion during the process of parturition (birth)
Which best explains what happens when you have a fever?
The body's set-point temperature is increased, causing temperature control mechanisms to maintain homeostasis at a higher body temperature
Which best describes how the total body balance of any chemical substance is determined?
The difference between the amount of substance lost from the body and the amount gained the body
Basolateral side
The region of an epithelial cell's membrane that faces the interstitial fluid
Which generalization about homeostatic control systems is NOT correctly stated?
The set points of physiological variables regulated by homeostatic controls do not vary-- that is, they cannot be reset from their normal values.
Which example is a local homeostatic response?
When a tissue is metabolically active, blood, vessels within that tissue dilate to allow more blood to flow into it.
Which describes a homeostatic control system?
When blood glucose becomes elevated above normal, hormones are released that cause glucose uptake from the blood into cells
A neuron is
a cell of the nervous system that is specialized to initiate, integrate, and conduct electrical signals to other cells
What is a term describing a reflex that only occurs after a conscious effort and repeated practice?
acquired reflex
The tall slender body shape that helps to dissipate heat in people in native to equatorial regions is an example of
an adaption
The hormone insulin enhances the transport of glucose into body cells. Its secretion is controlled by a negative feedback system between the concentration of glucose in the blood and the cells that secrete insulin. Which of the following statements in most likely to be correct?
an increase in blood glucose concentration will stimulate insulin secretion, which will in turn lower the blood glucose concentration
musculoskeletal system
bones, cartilages, joints, skeletal muscle
nervous system
brain, spinal cord, nerves
Identify the types of muscle tissue.
cardiac, skeletal, smooth
The term used to describe the process of transforming and specialized cell into a specialized cell type is
cell differentiation
The simplest structural units into which a complex organism can be divided that still retain the functions characteristics of life are called
cells
Level of organization of the body in order from least to the most complex
cells, tissues, organs, organ systems
________ tissue cells form teh extracellular matrix that exists around and between body cells
connective
Which of the following are general tissue type of the body?
connective, nervous, epithelial, and muscle
what is significantly different between the interstitial fluid compartment and the plasma in nearby capillaries?
dissolved protein concentration
What best describes the state of homeostatic variables?
dynamic constancy within a range
The type of tissue that covers the body surface and lines the inner surface of tubular and hollow structures such as the trachea and gut is
epithelial tissue
When a particular extracellular fluid variable is not changing and no input of energy is required to maintain the constancy it is said to be in a(n) ______ state; if energy has to be added to maintain the constant condition it is called a(n) _______ state
equilibrium, steady
True or false: homeostasis implies that a given physological function or variable is rigidly constant with respect to time
false
What type of regulation anticipates changes in variables and helps minimize fluctuations in the level of the variable being regulated?
feedfoward
organs are organized into small, similar subunits often called ________ units, each of which performs the main process of that organ.
functional
reproductive system
gonad, external genitals, ducts, glands
The concentration of dissolved protein in plasma is ___________ than the concentration of dissolved protein in interstitial fluid.
greater
integumentary system
hair, skin, nails
circulatory system
hear, blood vessels
The maintenance of a relatively stable internal environment is termed
homeostasis
Which pair is the most similar in composition?
interstitial fluid and plasma
Which of the following body fluid compartments has the greatest percentage of total-body water?
intracellular fluid
Examples of organs
liver, kidney
Claude Bernard was a physiologist who first recognized that _______ is a prerequisite for good health
maintenance of a constant internal environment
Of the four general tissue types, the one that is specialized for generation of mechanical force is _________ tissue
muscle
generation of mechanical force is a function that is most characteristic of
muscle tissue
Body temperature is regulated around a set point of 37 degrees Celsius by a _____ feedback loop.
negative
A burn patient ingests 100 grams of protein per day and loses 110 grams of protein per day to the injury. What is the overall protein state of the patient?
negative protein balance
An elongated structure composed of a group of neuronal extensions packaged with connective tissue that carries signals between the nervous system and other parts of the body is called a nerve
nerve
Some neurons in the vagus nerve have synaptic connections to sinoatrial (pacemaker)cells in the heart. These neutrons secrete acetylcholine, which ultimately results in a decreased heart rate. This is an example of
neural control
After spending several days at a high altitude, where oxygen pressure is low, a person will begin to produce more red blood cells, which enhances the ability of blood to carry oxygen to the tissues. what term best describes this type of response?
physiological acclimatization
A _______ is a specific, involuntary, unpremeditated response to a particular stimulus.
reflex
A homeostatic control system works to return a physiological variable toward its
set point
When a person has a fever, the _____ ________ temperature is reset to a higher value, inducing mechanisms that increase the body temperature
set point
If a person begins to sweat upon entering a hot room but continued sweating is able to keep th ebody temperature constant, which of these best describes her condition?
she is in a steady state
What types of muscle tissue are involuntary
smooth, cardiac
In the negative feedback homeostatic reflex involved in thermoregulation, where does the comparison between the normal set point and the current temperature status occur?
specific integrating neuron in the brain
What is primarily composed of nervous tissue?
spinal cord, nerves, brain
Negative feedback occurring at the cellular level, which would result from taking a drug that inhibits the activity of enzyme B?
substrate and intermediate 1 concentrations would increase, while intermediate 2 and active product concentrations would decrease.
apical side
the region of an epithelial cell's membrane that faces away from the interstitial fluid
Which situation describesa feedward mechanism
the smell of rotten food on a plate triggers the vomit reflex
Epithelial cells are held together along their lateral surfaces between the apical and basolateral membrane by extracellular barriers called ________ junctions
tight
What is the general purpose of positive feedback mechanisms?
to bring about a rapid change in the body
True or False: Hormones released by endocrine glands can participate as components of homeostatic reflex arcs
true
The primary component of intracellular and extracellular fluid is _______-
water
