32 - Homeostasis and Signaling Flashcards
Tissue Layers Versus Tissue Types
Layers refer to the argument of cells in their spactial organization within a tissue
Types refer to the category of the tissue based on its function, composition, and organization
Protective Barrier
Diffusion of ions and molecules (Nutrients)
Interact environment
Exterior surface of the body
Internal cavities and passageways
Some Glands
Epithelial cells
Epithelial
Contracts to initiate movement voluntary/involuntary
Skeletal muscles – involuntary
Cardiac muscles - heart
Smooth muscles – GI tract (digestive tract), cardiovascular
Muscle cells (myocytes)
Muscular
Transmit and integrate information through the central and peripheral nervous system.
Brian
Spinal Cord
Nerves
Neurons – send signals
Glial cells – support nervous system/maintenance
Nervous
Underlines and supports other tissue types.
Throughout the body
Bones
Ligaments
Tendons
Blood
Various connective tissues
Bone
Ligaments
Tendons
Blood
Connective
Some variables maintained in homeostasis?
Temperature
Blood pH
Blood sugar
Blood pressure
Hemoglobin
Oxygen levels (C02 levels)
Heart rate
Water balance/salt (osmoregulation)
Detoxification
Waste management
Inflammation
ECT…(many more)
Can organisms be regulators and conformers for different factors?
Yes - Organisms can be both regulators or conformed with respect to a condition.
4 Types of Heat transfer
Radiation
Evaporation
Conduction
Convection
Radiation
emissions of EM (electromagnetic waves) Sun
Evaporation
Loss of heat due to liquid-to-gas transition (humans sweat)
Conduction
direct transfer of heat between molecules in contact with each other
Convection
Increase in heat transfer due to movement of liquid or gas (fluid does not mean liquid)
How do humans thermoregulate when Hot?
Stimulus -Body Temperature Increases
Sensor -The thermostat in the hypothalamus activates the cooling mechanism.
Response - Blood vessels dilate in skin & Sweat
Negative feedback -Body temperature decreases
Why Negative – Body returned to normal
How do humans thermoregulate when Cold?
Stimulus - Body temperature decreases
Sensor - Thermostat in hypothalamus activates warming mechanism
Response - Shivering / Blood vessel constrict
Negative feedback - Body texture increases.
Why Negative – Body returned to normal
Water Soluble Hormones
Be in the blood (bind to an extracellular receptor to get through the phospholipid bilayer)
Made of amino acids and peptides
Hydrophilic dissolve in water
Rapid Response
Insulin, Growth Hormone (GH) , Adrenocorticotropic hormone (ACTH)
Lipid Soluble Hormones
Needs carrier protein (enters target cells by going through the membrane)
Steroids and Thyriod hormones
Hydrophobic do not dissolve in water
Slower but longer affect
Testosterone, estrogen, thyroxine (T4)
Endocrine
Entire organism
Slower signaling
Longer duration
Neuroendocrine
Generally, involve the hypotheses (release / send nerve impulse)
Sensors that is off will release a hormone and pituitary response by releasing hormones.
Negative feedback
Negative feedback counteracts the stimulus to return to the set point Negative refers to changing direction, not positive or negative values of change (Almost all)
Positive feedback
Positive feedback occurs when the orgasm wants to ensure the process reaches a particular outcome (rare) Milk production for offspring (Oxytocin pathway)
In what ways can a single hormone have multiple effects on an organism?
Different cell types have receptors – and respond differently based on cell type.
Type of receptor – may have multiple types of receptors for the same hormone – that each lead to different responses.
The concentration of hormones can make a difference (high/low does different things)
—— water (water outside) – excretion of salt ions in small amounts of water in scanty urine from the kidney
Saltwater fish osmosis
—— water (water inside)- excretion of salt ions and large amounts of water in dilute urine from the kidney
Freshwater fish osmosis
Ectotherms
the heat from external sources can regulate temp through behavior
