Test 1 Flashcards
Define
Physiology
study of the functions of an organism and its constituent parts
term physiology means the “study of nature” derived from the greek work physiologoi
What are the 3 strands of cellular physiology
- cytology - cell structure
- biochemical - chemistry of biological structure and function
- genetics - information flow
Who was Henrietta Lacks
1951 cervical tumour cells were removed from her
- these cells grow very well in culture and do not age or die
- names HeLa cells
- used in research on viruses, cancers, and AIDS (cited in more than 70,000 research papers, plays and important role in the polio vaccine development)
- Today: used for COVID vaccines, human genome, effects of toxins, drugs, hormones, radiation, poisons…)
What is cell theory
- all organisms are made up of cells and their products
- new cells arise only from preexisting ones
- all cells have the same fundamental makeup
- activities of an organism result from the co-operative working of groups of cells
- cells depend on one another to survive
Characteristics of Living Matter
- complicated and highly organized
- each constituent has a specific function
- extracts energy from the environment and synthesizes own complex structures from simple raw material
- capable of precise reproduction
What is integration (in terms of human processes and systems)
process by which several components work together for a common, unified purpose (eg cardiac system works in tandem with the respiratory system)
What are the 6 Life processes?
- Metabolism
- Responsiveness
- Movement
- Growth
- Differentiation
- Reproduction
Life Processes
Metabolism
what is it? what is it composed of?
Is the sum of all chemical reactions in the body.
Composed of:
* Catabolism - the breakdown of complex chemical substances into simpler components.
* Anabolism - the formation of complex chemical substances from smaller, simpler components.
Life Processes
Responsiveness
Is the body’s ability to detect and respond to internal and external environmental changes.
* Cells of the body respond to environmental changes in characteristic ways
Life Processes
Movement
Is motion of the whole body, individual organs, single cells, and even tiny structures inside cells.
* Ex. Chewing food in your mouth, and grinding of food in your stomach.
Life Processes
Growth
Is an increase in body size that results from an increase in size of existing cells, an increase in the number of cells, or both.
* Could also include increased materials between cells
* Ex. Bone matrix
* Adipose cells (Size & Number)
* Muscle cells (size - hypertrophy, number of cells can increase until about 2 months old)
Life Processes
Differentiations
Is development of a cell from an unspecialized to a specialized state. Each type of cell in the body has a specialized structure and function that differs from that of its precursor cells.
* Ex. Red blood cells come from unspecified cell in bone marrow
* Precursor cells that undergo differentiation are known as stem cells.
Life Processes
Reproduction
Is either:
1. the formation of new cells for tissue growth,
repair, or replacement
2. the production of a new individual.
Why do we have feedback systems and feedforward control?
there are constant disturbances to the bodies homeostasis which must be regulated and controlled
feedback systems function to regulate
What is a negative feedback
Reverses a change in a controlled variable
How many variables in the body are controlled?
What is positive feedback?
strengthens or reinforces a change in a controlled variable
* blood clotting and platelets are a positive feedback loop
* stretch receptors in the cervix during childbirth
what is feedforward?
Events which occur in anticipation of a change in a controlled variable
* mouth watering when before a tasty meal
* increase in heart rate before the start of a race
Homeostatic imbalace (pathophysiology)
what does this lead to?
Can often lead to disease or death
* Disorder - Abnormality in function or structure
* Disease - Illness characterized by a recognizable set of signs and symptoms.
* Signs - objective changes that a clinician can observe and measure : fever or tired & thirsty (diabetes)
* Symptoms - subjective changes in body functions that are not apparent to an observer : headache
Cellular Processes
(8)
■ Digestion
■ Energy Release and Consumption
■ Protein Synthesis
■ Lipid Synthesis
■ Packaging
■ Transport
■ Export
■ Cell Duplication
What is the role of membranes?
- compartmentalization: separates the cytoplasm (cytosol & organelles) from the ECF
- Regulation of substance movement within and between cell
- Detect arriving chemical messengers Link adjacent cells
- Anchor cells to extracellular matrix
Describe Membrane Structure
■ Mostly lipids & proteins
– Protein content is proportional to metabolic activity of the
membrane.
■ Lipid types within the membrane
– Phospholipids: creates rigidity
– Sphingolipids(orglyco): helps connect cells, importnat for signalling, establishing blood type
– Cholesterol: fights rigidity
What is the role of cholesterol?
further reduces permeability to water
* compartmentalization
enhances membrane fluidity
* acts as a thermal buffer
* prevents chrystallization
* disrupts the hydrophobic interactions between phospholipids
