Body systems and reproductions Flashcards
What is homeostasis
the relatively stable state inside the body of an animal
- many animal organ systems are maintained homeostatically
How is homeostasis maintained?
- Through negative feedback relationships
- if the blood glucose or calcium rises, this sends a signal to organs responsible for lowering blood glucose or calcium
- the signal that restore the normal levels are examples of negative feedback
What happens when there is too much blood glucose level and too little blood glucose level
TOO MUCH: leads to fatigue
TOO LITTLE: dizziness and weakness
What are the two types of blood glucose homeostasis?
Insulin and glucagon
What is the difference between insulin and glucagon?
INSULIN: moves glucose from the body into the cells (lowers glucose level)
GLUCAGON: brings glucose out of storage when necessary(raises glucose levels)
How does insulin works?
After a meal, there is a rise in blood glucose, so cells in pancreas secrete insulin into bloodstream. Pancreatic cells secrete the right amount of insulin to counteract the rise in blood glucose. Liver and muscle cells store glucose and then the blood glucose returns to normal levels as excess glucose stored as glycogen and fat
How glucagon works?
When blood glucose level falls between meals, pancreas cells triggered to secrete glucagon into blood. Glucagon signals liver to release stored glucose into blood and then when the levels are high enough, receptors trigger liver cells to stop.
What is thermoregulation?
Homeostasis referring to the maintenance of a steady temperature state withing the animal. Is not present in ectothermic animals (lizard) but is present in endothermic animals (mammals)
Thermoregulation ( hot weather)
sweating (horses and humans - heat loss through evaporative cooling)
panting(most other animals pant to inhale air to cool the lung surface i.e dogs)
Thermoregulation (cold weather)
Hair follicles lifted upright to trap heat (goosebumps)
- muscles contract to cause shivering (more effective than exercise, because animal stay still)
What is the definition of osmoregulation?
homeostasis referring to the maintenance of a steady water balance within the animal (controlled by kidney)
What happens in osmoregulation?
- is the process of maintaining salt and water balance across membranes within the body
- necessary because animals constantly consume and excrete water and electrolytes
What does the respiratory systems do?
- facilitate gas exchange
- provide body cells with oxygen and remove carbon dioxide
- Lungs have very large surface area
for gas exchange between air
inside lungs and blood from
circulatory system
What does the circulatory system do?
- heart has two pumps that move blood through the pulmonary (lungs) and systematic circulations
What is the difference between arteries and veins?
ARTERIES: vessels that take blood away from heart
VEINS: vessels that take blood towards the heart
What is the endocrine system?
Is a collection of glands in an organism that secrete hormones into the circulatory system, hormones cause cellular changes by binding to receptors on target cells
- hormone levels are controlled through negative feedback
- when hormone levels are high, receptors trigger glands to stop producing more
- glands that produce various hormones located throughout the body
What is difference between pituitary gland, thyroid gland, parathyroid gland, adrenal gland and pancreas? (organs that produce hormones in human beings)
PITUARY GLAND: in brain
THYROID GLAND: in neck
PARATHYROID GLAND: on top of thyroid glands
ADRENAL GLAND: on top of kidneys
PANCREAS: in abdomen between stomach and intestines
What does the human muscoloskeletal system do?
provides structure, support and allows movement
What is the difference between the axial and appendicular skeleton?
AXIAL: bones of skull, vertebral column and ribcage
APPENDICULAR: upper and lower limbs and pelvis
What is the definition of fibrous joints?
bones held together with fibrous connective tissue ( no movement possible)
what is the definition of cartilaginous joints?
bones connected by cartilage ( a small amount of movement is possible)
What is the synovial joints?
have a space between adjoining bones (allows bones around it to move, incorporates a fluid to enable that movement or flexibility)
What does the human nervous system do?
transmits signals between different body regions
- coordinates voluntary and involuntary actions
- made of neurons and glia
What is the definition of glia?
non - neuronal cells that support neuronal development and signaling