Unit 1: Chapter 2: Control of the Internal Environment Flashcards
Homeostasis
Maintenance of a relatively constant and “normal” internal environment
(Resting conditions)
(Heart rate, Body core temp. Arterial blood pressure)
Steady State
The physiological variable is unchanging but not necessarily a “normal” resting value.
Like heart rate for submaximal exercise (heart rate stays elevated)
How to gain control of a system?
The degree to which a control system maintenance homeostasis (precision or capability of the system)
Large gain (like breathing out CO2)
What are examples of homeostatic control?
Regulation of body temperature
Blood vessels and sweat glands regulate the
temp
and regulation of blood glucose
Elevated glucose releases insulin
What does exercise test?
Your homeostatic control
Asult to homeostasis
(exercise changes pH)
What is Positive Feedback?
Biological response increases the original stimulus
(Blood clotting, childbirth, fever response)
What is Negative Feedback?
Response reverses the initial disturbance in homeostasis
(Cold, heat, etc.)
What are 3 components of the biological system that maintain a constant value?
Sensor or receptor — Dedects change.
Control center —Makes a decision.
Effector — Actions
What is fatigue?
The inability to maintain homeostasis
Failure of a biological control system results in ——
disease
Body is unable to maintain homeostasis on it s own
Like diabetes + insulin
Most Biological control systems can only maintain a steady state at —— Levels
Submaximail
Adaptation
Change in cells to improve the ability to maintain homeostasis
Acclimation
Adaptation to environmental stress that improves homeostasis
Hormesis
Low-to-moderate doses of potentially harmful stress create an adaptive response.
Body adapting to tolerating stress
Exercise-induced hormesis——Protein Synthesis
What is Exercise-induced Hormesis?
adaptation in the body due to exercise
You need the optimal exercise training of intensity;
—Not too much—Can’t adapt
—Not too little—Not challenging
What is an example of Hormesis example?
Protien synthesis//
Hypertophy
What is Cell Signialing.
What are two of its functions?
Communication between cells using chemical messengers;
1) Coordinates cellular activities
2) Important for maintaining homeostasis
Intracrine Signaling
Chemical messenger inside the cell triggers responses
Autocrine Signaling
Chemical messengers act on that same cell (membrane receptors)
Leaves the cell and connects with its own membrane
Juxtacrine Signaling
Chemical messenger passed between two connected cells.
(Cells connected/touching)
Paracrine Signaling
Chemical messengers act on nearby cells
Endocrine Signaling
Chemical messengers (that is, hormones) released into the blood.
Affects cells with specific receptors to the hormone
What is an EV? What type of signaling does it do? When is it released, how does it travel?
Extracellular Vesicles— Ev’s are small membrane-bound sacs that carry cargo (RNA + Proteins)
EVs — A signaling mechanism that can participate in both paracrine and endocrine signaling.
Released after exercise travels in the blood
—..
What is a stress protein? What is an example? What can cause it?
Stress Proteins—Cells that synthesize when homeostasis is disrupted. It adapts so it can overcome it next time.
Heat shock proteins —proteins that unwind under heat. So, the heat shock proteins repair damaged proteins in cells.
Too much exercise
