First Test Module Two Flashcards
What is homeostasis?
A stable state that is actively monitored and constantly maintained (stable state)
What is negative feedback?
When a change in one direction causes a system to alter itself so that it causes enough of a change in the “opposite direction” to undue or reverse the original change
What is positive Feedback?
When a change in one direction causes a system to make another change in the “same direction”, which causes yet another change in the same direction, continually amplifying original change
What is equilibrium?
A state of balance or equality
What is a hypothesis?
A proposed explanation made on the basis of limited evidence as a starting point for further investigation
What is a theory?
Something scientists are very confident in, not something they are certain about
What is homeostasis and how is it maintained? Components used?
Homeostasis is a stable state and it is maintained by either negative or positive feedback, and the components used are a receptor, a control/integration center, and an effector
How does negative feedback work?
The receptor detects change from desired condition , then the control center determines what response is necessary to reverse change, finally the effector carries out response identified by control center that reverses change
What are biological and non biological examples of negative feedback?
Non-biological: Thermostat and temperature regulation
Biological: Hypothalamus and temperature regulation
How does positive feedback work?
The sensor detects change form desired condition, then the control center determines what response is necessary to amplify change, and finally the effector carries out response identified by control center, producing more change, activating receptor further
What are biological and non biological examples of positive feedback?
Non-biological: Nuclear chain reaction
Biological: Blood clotting, Child birth, Lactation
What is the difference and similarities between negative and positive feedback?
Both are similar because they both are functions used to maintain homeostasis and they differ because negative feedback by its mechanism, undoes change and positive feedback by its mechanism, increases change
What are the four characteristics of science?
- It is a process
- It provides explanations and mechanisms
- It is self correcting
- It makes falsifiable predictions
How do experimental controls work and what info do they provide?
It is a slight variation on the experimental group that is designed to rule out alternative explanations for positive results and they allow us to see a change
What does the “same” in the “homeo” part of homeostasis refer to?
Conditions in one location being kept the same
What is optimal human blood pH?
pH 7.3
What is optimal stomach pH?
pH 2
What is optimal small intestine pH?
pH 8
What receives and sends out signals and sends out commands in the homeostatic system?
The integration center/control center
To maintain homeostasis and keep conditions constant you need three components:
- Receptor or sensor
- Control/Integration center
- And Effector
What does the receptor/sensor do in maintaining homeostasis?
To monitor conditions under homeostasis and detect changes from the optimal or desired setting
What does the control center/integration center do in maintaining homeostasis?
To receive signals/information from receptor/sensor and respond to any detected changes by sending out commands
What does the effector do in maintaining homeostasis?
To receive commands from the control/integration center and carry out actions in response to the changes detected by the receptor/sensor
In negative feedback what direction is the response in?
The opposite direction to the original change
In positive feedback what direction is the response in?
In the same direction as the original change
Why do we call science a process?
Because it is a way of generating and evaluating explanations
What is an example of science self correcting?
Newtons law of gravitation lasted 200 years until Einsteins theory of gravitation better explained very precise observations and after the 1920s supplanted Newtons theory
Why do we attempt to provide explanations and mechanisms for what is observed in science?
Because observations and descriptions are not enough
Why do we call science self correcting?
As part of process of accumulating new knowledge, existing explanations are always being compared to latest knowledge and therefore there are no untouchable explanations
Why do we call science testable and falsifiable?
Because any scientific explanations must include predictions that can be tested, and there must also be some kind of result that, if it happened, would prove the explanation false
Is a falsifiable prediction a prediction that is false?
No. It is a prediction that has at least one way of being proven false but you think is probably true
What are 3 reasons why some scientific hypotheses can not have their predictions tested in experiments?
- Predictions that involve things that happened in the past
- Predictions that involve things that are very slow
- Predictions that involve things that are very large
The key component of any scientific explanation is?
That it makes testable and falsifiable predictions
Are experiments required by the scientific method?
No, but they are a favorite way to do it.
Are testable and falsifiable hypotheses about things in past still possible?
Yes. 1. Make predictions about other things in past they should have had an effect on. 2. Make predictions about things in the present they should have influenced. 3. Check whether predictions are accurate
Are testable and falsifiable hypotheses about things that are slow still possible?
Yes. 1. Make predictions about what effects actions in past have on the present. 2. Check whether predictions are accurate
Are testable and falsifiable hypotheses about things that are very large still possible?
Yes. 1. Make predictions about how the object’s size, position, or movement effects things around it. 2. Check whether predictions are accurate.
What kind of hypothesis would be tested by the prediction that background stars shift with different seasons?
One about thing too large to experiment on
A well designed experiment should always include at least one(often more than one) ?
Control
What is a experimental control/control group?
A slight variation on the experimental group that is designed to rule out alternative explanations for positive results
What does the control rule out?
Alternative explanations for positive results
What is a controlled experiment?
An experiment that includes controls
What is a well-controlled experiment?
If a experiment includes many controls
What is an ideal control?
A variation in which everything is identical to the experiment, except one thing
What is anatomy?
the study of the structures found inside the outside living things
Did we concluded anatomy was a science?
Yes. at advanced levels, it makes testable and falsifiable predictions
