Final exam Flashcards
common challenges for multicellular and multi-tissue organisms
- support
- gas exchange
- nutrient transport
- water removal
- water balance
- temperature maintenance
- communication/control
convergent evolution
results in similar adaptations of diverse organisms facing the same challenges
multicellular animal with sac-like structures
tissues layer that are 2-cells thick, each cell uses diffusion for molecule exchange, early plants have similar adaptations
examples of flat multicellular organisms
seaweed, flatworm and nudibranch mollusk
what causes diverse life forms to emerge?
competition and natural selection
what emerged from the sac-like animal form as a result of competition and natural selection?
cells bathed in interstitial fluid for exchange rather than external fluid, tube like form with specialized organ along the tube
how did animals increases surface area as they evolved?
branching and folding
purpose of organ systems working together
maintain homeostasis
list of 4 main types of animal tissues
- epithelial
- connective
- muscle
- nervous
epithelial tissue
- cover and line body
- cells are tightly joined together
- can be simple or stratified
connective tissue(list types)
- consist of fibrous tissue, loose connective tissue and mineralized connective tissue
- bind and support other tissues
- have many specialized cells
- sparsely packed cells in extracellular matric of protein fibers
Loose connective tissue
binds epitelial tissues, holds organs in place, adipose, blood
fibrous connective tissues
tendons, muscle, bone, and ligaments
ligaments
fibrous connective tissue that holds joints
mineralized connective tissue
bones, osteoblasts and osteoclasts
list of types of muscle tissue
- striated
- smooth
- cardiac
striated tissue
muscle tissue responsible for voluntary movement
general purpose of muscle tissue
different arrangements of actin and myosin fibers
smooth tissue
muscle tissue responsible for involuntary movements
cardiac tissue
muscle tissue responsible for contraction of the heart
purpose of fibers in tissue+example
fibers give strength and flexibility(collagen), join connective tissue to other tissues
elastic fibers
snap back to original shape and origin
nervous tissue types and function
- Neurons: transmit impulses
2. glial: support cells
how do organisms overcome the challenge of moving molecules?
tissues, organs and organ systems
how do organisms overcome the challenge of coordination and control
multi-tissue and multi-organ systems
Endocrine system
- hormones are released upon receiving a signal
2. often in conjunction with nervous system
endocrine system signaling
stimulus is received by endocrine cell and signal travels everywhere, releasing hormones
neuron signaling
stimulus reaches cell body/neuron and travels to a specific location, causing a nerve impulse and traveling to the axons
what regulates internal environment?
control mechanisms
strategies for maintaining balance(types+functions)
- regulator: internal mechanisms maintain internal setpoints despite external changes
- conformer: internal conditions can vary with environmental changes
how can an organism be a regulator and conformer simultaneously?
they can be a regulator for one environmental aspect and a conformer for another aspect
how do trees survive freezing temperatures?
increase fluidity of membranes and add sugar to xylem and phloem to act as antifreeze
types of heat exhchange in animals
- radiation
- evaporation
- convection
- conduction
heat exchange in endotherms
keep internal temp constant but out layers can change. On a cold day warm blood comes from the arteries and outer vessels constrict to reduce heat loss, inner vessels dilate to allow blood to bypass colder surface vessels, vice versa on a hot day
counter-current strategy
a strategy for heat exchange, in which warms veins are near cold veins to give heat to the cold veins
long term endotherm heat regulation strategy
they acclimatize after prolonged exposure to an environment
gland repsonsible for thermoregulation
thyroid gland
steps of a homeostatic challenge
homeostatic challenge, sensor, integrator, effectors repsonse
how are hormones regulated?
positive and negative feedback, mostly negative
injury(bleeding) response in animals
- Challenge: injury
- sensor: blood vessels detect blood loss, signal is sent
- brain(integrator) receives signal
- brain signals effectors(Kidneys, heart and blood vessels) using hormones and nerves
- Blood pressure is raised back to normal by kidneys decreasing urine production, heart rate and pressure increasing, and blood vessels directing blood flow to vital organs. This results in removing the stimulus of the sensor
how do feedback mechanisms work at different levels
- molecular: transcription and translation
- Cellular: turn metabolic pathways on/off
- organ level: respond to internal and external stimuli
purpose of excretory system
regulate water and solute/electrolyte balance to keep their concentrations in a specific range
osmoregulation
mechanisms to control solute concentrations by taking in and letting out water
general purpose of kidneys
clean out waste products from blood to urine using active transport
molecules with high permeability
gases have the highest then very small and uncharged polar molecules
molecules with moderate permeability
water and urea
molecules with low permeability
polar organic molecules, glucose
molecules with very low permeability
ions, charged polar molecules and macromolecules(amino acids, ATP, proteins, etc)
what does the excretory movement depend on to do its job?
movement of water and solute across membranes
how does water typically move?
facilitated diffusion
how do solutes typically move?
facilitated diffusion and active transport
what follows ions and solutes when they are pumped out?
water
hypotonic vs hypertonic cells
hypotonic: fills with water, lysed cells
hypertonic: water leaves cell, cell shrivels
what kind of adaptations for water do land animals have?
adaptations to reduce water loss. they have body coverings, good food from water and have metabolic water
what affects how animals deal with water?
its surrounding environment
osmoregulation in a marine fish
gets water and salt ions from food, excretes salt ions through gills, loses water from gills and body surface, drinks seawater, urine excretes salt and small amounts of water from kidneys
osmoregulation in freshwater fish
gains water and ions from food, gills uptake ions, water enters through gills and body surface, excrete salt ions and large amounts of water in dilute urine from kidneys
metabolic water
adding electrons to oxygen and combining with H+ to produce water
How are salt water fish able to drink water?
they have specialized organs to remove the salt from the water
how do sea turtles secrete salt?
through their eyes
What is the main water obstacle for freshwater fish and how do they deal with it?
they have to prevent too much water from coming in so they secrete it in their waste products
What is special about salmon and their environment(s)
they live in the ocean but swim up freshwater streams to reproduce
tardigrades
found everywhere, have 8 legs, unique, resistant to heat/uvrays/dessication, they can be ressurected when you add water
dessication
removal of water
milk fever
happens in female cows after having babies, they have a depletion of Ca in their blood because they are giving milk. They collapse because they need Ca to contract muscles
How was gatorade invented?
ions in the sweat of athletes were analyzed and then salt and sugar were added to it to make a drink that replaces the exact electrolytes lost when sweating
what determines how expensive it is to make urine?
bigger difference between inside and outside environments/concentrations makes it more expensive to make urine. It is also determined by how easily water and solutes cross the body covering(permeability) and the amount of pumping required.
fluid filtration and waste removal process
takes place in specialized transport epithelium that are organized to control movement of solutes in specific directions.
what happens when a substance get’s filtered into the urine that the body needs?
it gets reabsorbed into the body again
what are internal structures surrounded by?
interstitial fluid
how does slat excretion in marine birds work?
there is more salt on the blood side compared to the kidney side that undergoes the countercurrent exchange via facilitated diffusion. Tubules made of different proteins carry the salt. They have nasal salt glands and secrete it through their beak. Vein called capillary secretory tubule and tubules are separated by transport epithelum
nitrogenous waste
all animals secrete nitrogenous waste because it is toxic in order to balance waste and water toxicity
nitrogenous wastes from most to least toxic or cheapest to most expensive
Ammonia, urea, uric acid
which nitrogenous wastes requires the most water?
ammonia because it is most topic, so it needs to be diluted most
protonephridia
organ in flatworms that use filtration through flame cells, solutes are absorbed back into the interstitial fluid and then waste exits through pores. They have no kidneys
How do insects get rid of wastes?
they use secretion more than excretion, they have an open cirulatory system, hemoplymph flows inside to pick up waste products, insects produce waste called frass, malpighian tubules extend into hemolymph
hemolymph
salts, uric acid and water
what allows freshwater fish to urinate inexpensively
they are surrounded by water
What is urine like in freshwater fish and how is it produced
rapid filtration, very dilute
urine of desert animals
very concentrated
what impacts the function of the vertebrate kidney?
the evolutionary/life history of vertebrates
what is the loop of henle made of?
long portions of nephrons
functional unit of kidneys
nephrons
purpose of kidney
clean blood, filter solutes for water and concentrate waste
artery and vein of kidney
renal artery/vein
from where does blood enter the kidney? where does it go after?
it enters from the renal artery, into the kidney, then to a nephron
Order liquid entering the kidney
- blood enters glomerulus
- filtrate enters Bowman’s capsule
- proximal convoluted tube
- loop of Henle
- distal convoluted tube
- collecting duct
- Renal pelvis
- Ureter
- bladder
- urethra
what does the kidney used to exchange solutes?
countercurrent exchange