Chapter 1 Flashcards
Human Physiology Definition
Study of how our bodies keeps us alive and functioning
Physiology vs Anatomy Saying
“Function Follows Form”. Neurons recieve information from many different sources but the anatomy allows us to see the dendrites and how they allow more contact and communication
Role of Physiology?
To understand how the anatomy is used to make these functions happen
What is Homeostasis
Maintaining Internal Equilibrium
Why is Homeostasis important?
External Factors: Room Temp, Pathogens
Internal Factors: Exercise
How is Homeostasis Maintained?
Negative Feedback
Homeostasis Maintenance Steps
Stimulus –> Receptor –> (Afferent Pathway/Sensory Pathway) –> Integrating Center –> Effector (Efferent Pathway/Motor Pathway) –> Response –> Negative Feedback
Result of Negative Feedback?
Maintenance of internal functions, maintains physiological “set points”
What about positive feedback?
Mechanism: Once one system becomes active, others begin to start activating as well. Essentially a chain. Short but rapid activity
Examples of Positive Feedback
Platelets –> Clotting. Sacrifice one point in order to maintain overall equilibrium.
Increase of Estrogen prior to Ovulation
Calcium Release in the muscle
How does positive feedback fit in with the idea of homeostasis?
We sacrifice one point to maintain overall system
Hierachy of Physiology
Atoms - Smallest functional form (O2) Oxygen.
Ions . Low pH = High [H+] = Acidic. High pH = Low [H+] = Basic
Negative Feedback while walking on a balance beam
If you start leaning, body senses that you’re out of balance and negative feedback is triggered and tries to recenter itcelf.
Small Molecule Examples
H20, CO2, C6H2O6, Amino Acids
Large Molecule Examples
Fats, Proteins, DNA
Why does molecular size matter?
Ease of movement when smaller; Crossing Membrane
Amount of energy stored. Larger energy = More atoms which means more bonds.
What is Polarity?
How equal electrons are shared within atoms. Some may draw elements closer than others
Polar Example
Water, GLucose, All Ions, Amine and Peptide Hormones
Non-Polar Types
Lipophilic (Soluble in Fat)
Hydrophobic (Not Water Soluble)
Non-Polar Examples
Lipids (Fats) , Vitamin A, D,E,K; Steroid Hormones
Why does polarity matter?
Solubility in water. We are mostly water
Membrane Permeability; How hard is it to get in?
Organelles Definition
Small organs for cell, maintain homeostasis in cell.
Mitochondria Structure
Outer and Inner Membrane. Matrix (Space) has a lot of enzymes with its DNA. We’ll see ATP there, produces it.
Ribosomes Structure
Only non-membranous. Made up of nucleic acid. Contains a large and small subunit. Will start process of making protein, connect to producing.
Ribosomes Function
ER has fixed ribosomes with it producing membrane proteins
Endoplasmic Reticulum (RER)
Membrane folded on top of each other to make chambers. RER has fixed ribosomes with it being expertive or four membrane proteins. This is the beginning of building proteins
Endoplasmic Reticulum (SER)
Adds lipid groups to a molecular of protein. It is specialized within muscles
Golgi Apparatus
“Mailroom of Cells”
Membranes fold to make chambers. Attaches carbohydrate groups to molecules (GLycoproteins). Serve as distribution point, determines where things go, can leave or stay in cell.
Nucleus
Digestive System of cells. Spheres of membrane to enclose enzymes. Creates chains of amino acids, –> Breaks bonds –> creates individual amino acids
Disease Associated with Lysosomes
Tay-Sachs Disease; Within the Lysosome. Don’t have one specific enzyme. There is one lipid they cannot absorb and break down. Cell gets crowded and dies
Cytoskeleton - Muscle
“Bone” of the cell. Have microfilaments and microtubules to maintain structural integrity. Aids in movement (Actin + Myosin). Provides track for internal transport.
Cytoskeleton - Cilia
Specialized cytoskeleton structure. Helps mucus go up throat.
Cytoskeleton - Microvilli
Located within digestive system. Increases surface ARea
Cells ; Plasma Membrane; Phospholipid Bilayer
Form sphers, head attracted to water while the water side repels it. Phospholipids group each other in water.
Hydrophobic vs Hydrophilic
The head is Hydrophilic while the tail is Hydrophobic
Relationship between molecular size and polarity?
There is no relationship, and there are no associations that exist
How do organelles fit into the concept of Homeostasis?
Maintain cells homeostasis, which form larger organs
How is homeostasis affected in Tay-Sachs Disease?
One enzyme is missed in a lysosomes and a certain fat can’t be destroyed.
Phospholipid Bilayer
More Lipid than Phosphate. Nonpolar because of the tail. Crossing depends on polarity.
Can water cross Phopholipid Bilayer?
Water has trouble crossing because it’s polar.
Can ions cross Phospholipid Bilayer?
No
What can cross Phospholipid Bilayer?
Non polar substances can cross and has access to cell and membrane
Membrane Proteins - Integral
Part of the protein imbedded within membrane. Help get polar molecules from one end to another
Example of Integral Protein
Ion Channel, Channel Proteins
Membrane Proteins - Peripheral
Not imbedded within membrane
Example of Peripheral Proteins
G-Proteins, Enzymes
Fluid Mosaic Model
Describes fluid within the plasma membrane. Explains how the structure isn’t rigid and how things move around
Membrane Functions
Physical Barrier
Transportation
Communication
Overall Structure
Membrane Functions - Physical Barrier
Allows cells to have internal homeostasis
Membrane Function - Transportation
Moving things in and our across membrane
Membrane Function - Communication
Electrical communication, ion movement among inside and outside
Membrane Function - Overall Structure
Structures within membrane which help it survive
Cytosol - Intracellular Fluid
2/3 Body Water is this. Water inside of cell.
High Concentrations of K+, Amino Acids, Glucose
