Homeostasis, Water, & Membranes Flashcards
(44 cards)
What is physiology?
A branch of biology that deals with understanding the functions and activities of living things
“How does the body actually work”
What is meant by an organism’s environment?
The totality of an organism’s surrounding conditions
What are the levels at which physiology can be studied? (largest to smallest)
Biosphere, ecosystem, community, population, individual, organ system, organ, tissues, cells, molecules, atoms
What are the different approaches to studying physiology? (name all 5)
- Mechanistic
- Comparative
- Environmental
- Integrative
- Evolutionary
What is the mechanistic approach?
Explains how events happen on a biochemical level.
Ex. How is heart rate controlled?
What is the comparative approach?
The studies of the similarities and differences of the vital processes found in various species to determine fundamental physiological relationships.
Ex. Comparative gas exchange in different animals.
What is the environmental approach?
The study of the environment’s influence on the physiological function and performance of living things.
Ex. What does a kangaroo do to compensate living in hot, dry environments?
What is the integrative mechanism?
Encompasses the broader aspects of physiology by integrating mechanisms at all biological levels ranging from the molecular, cellular, tissue, and organs.
Ex. How does a frog jump?
What is the evolutionary mechanism?
How does an organism’s physiology influence the way they evolve?
“Form follows function”
Ex. Different shaped bird beaks cater to their diet.
Which type of physiology focuses on the studies of similarities and differences of the vital processes found in various species of living organisms to determine the fundamental physiological relationships between members of the animal and plant kingdom?
Comparative Physiology
Why did organ systems evolve?
Organ systems evolved because larger organisms have a smaller surface area to volume ratio. This means that nutrients and oxygen cannot just reach deep into the inner volume of the large organism by diffusion from the skin. So, larger organisms need a more complex transport system to bring nutrients to all of the necessary places in the body efficiently.
What types of organisms need a transport system?
a. multicellular organisms
b. unicellular organisms
c. both
d. neither
multicellular organisms only
What is HOMEOSTASIS?
The ability to keep a relatively stable internal state despite the environment around us.
Homeostasis refers to stability, balance, or equilibrium within a cell or the body
What happens, due to homeostasis, when there’s a change in the environment? Basic.
The receptors sense changes in the environment, sending a signal to the control center, which, in turn, generates a response that is signaled by an effector.
In what ways can an organism mitigate spending energy on homeostasis? Explain.
- Avoidance.
- avoid the temperature fluctuations.
- Ex. Migrate somewhere else - Tolerance.
- just deal with it
- ex. hibernation
If the set point of the hypothalamus were to suddenly rise to 40 degC (as in the induction phase of a fever), what would the initial response of the body be?
a. glands release sweat
b. muscles contract to cause shivering
c. nothing
d. body temp drops
e. blood vessels dilate
B. Muscles contract to cause shivering.
This is because your SET POINT CHANGED but your body is still at about 37 degC. So now your body wants you to warm up, which causes you to shiver.
What is negative feedback?
The body compensating for a disturbance in a way that REDUCES the disturbance on the body.
What are the four steps of negative feedback?
A stimulus causes a deviation from the set point.
- Sensor: monitors the conditions of the body and detects the change
- Integrating Center: receives info from he sensor and compares the conditions to a the set point.
- Effector: receives information from the integrating center and effects/causes a change
- Response: movement back toward the set point
Homeostasis is maintained using negative feedback loops. Which part of a negative feedback loop detects conditions?
a. response
b. effector
c. sensor
d. integrating center
e. stimulus
C. SENSOR
What is positive feedback?
Body reacts to disturbance in such a way that INCREASES the disturbance.
What is feedforward?
Body anticipates future disturbance and PREPARES in a way that REDUCES the disturbance when it occurs.
Happens before the change occurs.
Ex. You have to go outside on a cold day and you get goosebumps before your core even gets cold.
When tissue is torn, a chemical is released. This chemical causes platelets in the blood to activate. Once these platelets have activated, they release a chemical which signals more platelets to activate, until the wound is clotted.
What type of feedback loop is this?
a. Positive
b. Negative
c. Feedforward
d. None of these
a. POSITIVE
The deviation creates more deviation
What is a molecule?
A group of atoms held together by energy in a stable associate
Ex. H2 , H2O
What is a compound?
A molecule that contains more than one element.
Ex. H2O, N2O
