Definitions
What is the study of comparative physiology?
the study of how different species have solved problems of life
Plasma membrane: functions
- Defines cell boundaries
- Controls interactions with other cells
- Controls passage of materials in and out of the cell
What are the membrane protein functions?
- Receptors, second-messenger systems, enzymes
- Channel proteins, carriers, motor molecules
- Cell-ID markers, cell-adhesion molecules
What two Western scientists were the first to realize that blood flows from the heart to the body and back to the heart?
(1) William Harvey
(2) Michael Servetus
Principles of Modern Cell Theory (4 bullets)
What are the four principles of the cell theory?
1. All living organisms are made up of one or more cells
2. Cells are the basic structural and functional units of all living organisms
3. All activities of an organism stem from the activities of its constituent cells
4. All cells arise from preexisting cells
What is inductive reasoning?
the process of making numerous observations until one feels confident in drawing generalizations and predictions from them
- Enables immune system to recognize normal cells from transplanted tissue, diseased cells, and invading organisms
- Cushions and protects the membrane
- Assists in cell adhesion, fertilization, and embryonic development
Who was the first to see and name cells?
Robert Hooke, who improved the optics and mechanism of the compound microscope (magnified 30 X)
How does negative feedback assist in homeostasis?
The self-corrective mechanism that underlies most homeostasis, in which a bodily change is detected, and responses are activated that reverse the change and restore stability to preserve normal body function
Hypethetico-deductive method
an investigator asks a question and formulates a hypothesis, an educated speculation, or possible answer to that question
How many organ systems are there? List them.
Eleven:
- Integumentary, muscular, cardiovascular, respiratory, nervous, lymphatic, skeletal, endocrine, digestive, urinary, and reproductive systems
What leads to cystic fibrosis?
Chloride pumps fail to create an adequate saline layer, so sticky mucus plugs pancreatic ducts and respiratory tracts (clogs up and bogs down the cilia)
Who is credited for concluding that all organisms are made of cells?
Schleiden and Schwann
Describe filtration—passive transport
Metabolism vs. Homeostasis
- Chemical reactions within a living organism,
- The tendency of a living organism to maintain relatively stable internal conditions in spite of greater challenges in its external environment
What is the breakdown from organism?
2. Organ
3. Tissue
4. Cell
5. Organelle
6. Macromolecule
7. Atom
Describe how osmosis functions. What is osmotic pressure?
From an area of more water (side B) to an area of less water (side A) = more dissolved solutes
- Aquaporins are channel proteins in cell membrane which are specialized for the passage of water — increase in aquaporins = increase in rate of osmosis
- Amount of hydrostatic pressure required to stop osmosis = osmotic pressure
- Osmosis slows down due to filtration of water back across the plasma membrane due to hydrostatic pressure
What is positive feedback?
self-amplifying cycle in which a physiological change leads to even greater change in the same direction
What is simple diffusion—passive transport?
- Net diffusion is the movement of high concentrations to an area of low concentration (down or with the concentration gradient)
Define osmosis.
The spontaneous passage or diffusion of water or other solvents through a semi-permeable membrane
Physiological gradient
A difference in chemical concentration, electrical charge, physical pressure, temperature, or another variable between one point and another
- Molecular motors engulf bacteria
- Traps it into a phagosome
- Brings together with it a lysosome = phagolysosome
- Bacteria neutralized, removed by exocytosis
What are two examples of active transport?
- Carrier-mediated: active transport, vesicular transport
*ATP is needed to transport particles against their concentration gradient!*
What is facilitated diffusion—passive transport?
- solute binds to carrier, carrier changes shape and releases solute on other side of membrane (no energy needed!)