Biol120 Quiz 1

Proximate: Immediate Causation

The physiological mechanism underlying the trait of interest.

Proximate: Development

The role of developmental timeline, experience in expression of the trait of interest.

Ultimate: Adaptive Function

The role of any structural, physiological, or behavioral process that increases an individual's likelihood of surviving and reproducing compared with other conspecifics.

Ultimate: Evolution

Role of phylogeny.

1st Major Theme of Physiology

Physiological systems require integration of multiple levels of organization.

2nd Major Theme of Physiology

Organismal structure is fundamentally related to function.

3rd Major Theme of Physiology

Feedback mechanisms drive physiology.

4th Major Theme of Physiology

Gradients matter (a lot!)

5th Major Theme of Physiology

Proteins are critical mediators of physiological function.

6th Major Theme of Physiology

Physiology Changes Over Multiple Time Frames.

Different levels of Organization

atoms, molecules, cells, tissues, organs, organ systems, populations of one species, ecosystem of different species, biosphere.

Example of anatomy relating to function.

Galapagos finches and their beak sizes.

Homeostasis

Maintenance of a relatively stable internal condition.

Negative Feedback

A mechanism of response in which a stimulus initiates reactions that reduce the stimulus.

The path of negative feedback into homeostasis

Negative feedback, sensors, integrator, effectors, then back to negative feedback.

Positive Feedback

Feedback that tends to magnify a process or increase its output. Must be pushed to completion and cannot go forever. Something must break the loop.

Gradients (give an example)

Particles in a gradient move high to low in a process called diffusion. Examples can be chemical (ion, oxygen, protein, etc.) electrical, thermal, or pressure.

Darwin's 4 Postulates of Natural Selection

-Variation between individuals

-Variation is heritable

-Different variants are expected to leave different amounts of offspring

-the subset that survive the best and produce the most offspring is not random

List and explain the different case studies of natural selection we went over in class.

-Tuberculosis case study where the disease mutated to resist the antibiotic, thus becoming deadly.

-Finch case study where a rainy season resulted in more finches developing the same length of beak over time to harvest food more easily from soft seeds.

Common Misconceptions of Natural Selection

-Natural Selection does not change individuals

-Natural selection is not goal oriented

-Natural selection does not lead to perfection