Animal Structure and Function...

Some examples of VERTEBRATE PHYSIOLOGY using what we've learned so far...
              structure & function of cells, tissues, & organs of vertebrates
      structural hierarchy...   cell --> tissue --> organ --> Organism
we'll try to apply some of the molecular principles we've looked to date.

    Model organism -
Organisms having a SPINAL COLUMN or BACK BONE...
                                                       a dorsal (along the back) set of nerves encased in bones. 


Verts... are members of phylum Chordata that includes most complex animals on Earth.
                 some 50,000 species:
 including amphibians, fishes, reptiles, birds, & humans, 
                        all with segmented spinal column & a distinct, well-differentiated head*
                       vertebral column - a winning evolutionary design resulting in fastest runners,
                                                       highest fliers, deepest divers, most agile climbers,

panda                                          and the best 150 students that ever lived...









Vertebrate Physiology...  lies in what the tissues of the major organs can do,
   at the cellular level physiology lies in: 4 Fundamental tissues common to vertebrates

epithelial connective muscle nerve
   their origin is

ectoderm mesoderm mesoderm ectoderm
                                        let's follow origin of cells from 1st embryonic cells...
                                        there are about 210 distinct human cell types 
                                        & between
50 and 75 trillion cells in the human body.
                                  Origins*   &   embryonic origins in sea urchin   &     frog  
                                  tissues derived from the 3 embryonic germ layers of vertebrates*

Properties of the Major Vertebrate Tissues    






   1.  EPITHELIAL - sheets of tightly packed cells that line body cavities* & organ surfaces
-  ectodermal origin
         -  prevents dehydration - forms a permeability barrier [to prevent loss of H2O]

      -  provide a
sensory surface, as well as a secretory layer 2
         -  typed by cell SHAPE
*:   squamous,  columnar,  cuboidal stratified  (wolf & pics)










CONNECTIVE - mesodermal tissues that function to BIND & SUPPORT  pics    

Adipose tissue - adipose (fat) cells
*, which insulate the body & store fat energy
      Blood - includes fluid (non-solid) matrix for RBC & WBC's transport     
*  H2O, salts, dissolved proteins  (hematocrit*)
      RBCs & WBC  (pics = lymphocytes - macrophages - a clot)
* - strong, but flexible skeletal material at end of bones made of
                          collagen & elastin fibers embedded in rubbery matrix

      Bone - mineralized rigid connective tissue [
NIH bone diseases site]
                          collagen fibers embedded with Ca++, Mg++, &  Pi salts for hardness

      Fibrous connective tissue - dense matrix collagen fibers
*... polysaccharides, proteins, water
 forms   ...tendons
- connects muscles to bone
                                ...ligaments - join bones to bones and together at joints

connective* - loose weave of fibrous proteins with lots blood vessels...
                                      binding & packing material holds organs & tissue in place

 orca                      Summary figure of Connective Tissues









Muscle & Nerve Tissue...

3.  MUSCLE... contractile tissue derived from mesodermal origins 
                        contains proteins actin & myosin = in filament
(thread-like) form
                        multi-nucleate cells that assemble into fibers called
                        human body has about 200 bones and more than 600 muscles
                        Muscle contractions shorten cell cell length & function to produce force & motion.

          3 kinds:     a)  skeletal
...  striated appearance in microscopy - voluntary control
                           b)  cardiac...   striated, but branched, in heart - involuntary control
                 c)  smooth...   in organ walls, non-striated - involuntary
                                                 picture of types in a wolf* & in a chimp*
                                                 role of skeletal muscles & tendons* in human body

4.  NERVE...  tissues made of cells that conduct electrical impulses for communication
                      have an ectodermal origin.

          2 kinds    a)  neurons* - electrically excitable cells of nervous system
 glial cells* (astrocytes - pic)-  non-conducting cells that
                                                 surround, support, insulate, & protect 

 panda                 summary figure of vertebrate tissues










ORGANS - systems made of the 4 tissue  types above (& some others), 
                      which catalyze a physiological process (some specific function

                 The eleven main vertebrate animal ORGAN SYSTEMS...        

a. digestive  g. reproductive

b. respiratory  h. nervous

c. cardiovascular i. muscular

d. lymphatic & immune j. skeletal

e. excretory k. integumentary
  f. endocrine

                 ... are the subject matter of Biology 360 - Comparative Physiology:
                                                       animal and plant physiological processes.

 orca                       Organs on Demand    &   3D-printing (tissue engineering)










Part 3:   VERTEBRATE  PHYSIOLOGY...  to apply some concepts we've seen so far:
    Vertebrate Physiology is the study of how vertebrates function, often
measured by...
    Metabolic Rate
- total energy used by organisms per unit time, in doing biological work.
      Animal Bioenergetics... 
                  energy needed to do vertebrate physiology:  
                                                to walk, run, swim, or just to be...
  How does one measure energy metabolism?  i.e.,  the METABOLIC   RATE  (MR)...
     measured in calories  =  amt of Heat Energy
                              1c  = energy required to raise 1g water 1
oC  [14.5o to 15.5o
]  1c = 4.2 joules
1C = energy required to raise 1 kilogram of water  (1C = 1Kc)  
minimal  Cal  -->  the energy required for basic functions of life (to be)
?   maximal Cal  -->  for peak metabolic activity -->
Olympic swimmer
* Let's link Cell respiration (Krebs & ETC) to Metabolic Rate
                                 by determining O
2 consumption reported as  VO2MAX
glucose --->  CO2 + NADH + FADH2 + ATP ---e--->  O2 + H ---> H2O
            oxygen consumption is thus related to rates of cell respiration (exercise)

    VO2max...  is determined using 'stress' measuring equipment such as...
                   respirometer*,    oxygen meters,    a cycle ergometer*,
*mill or bike   or  measuring VO2max [even in swimming]*.












Vertebrate Physiology or the Science of Physiology...  

   often monitors... 
VO2 max [Metabolic Rate] as influenced by many variables  as... 
                               age,  sex,  body size,  temp,  food levels, disease state,
                               time of day
, size of organism,  hormonal balance
available O2
BMR - basal metabolic rate - heat calories used @ rest w/o stress by endotherms  
              ex: humans -  
males   1,600 - 1,800 Kc/d     females   1,300 - 1,500 Kc/d 
                 athletes are often naturally selected for their sports due to unique
anatomy/physiology, as well as their aerobic capacity:

Michael Phelps:      is he a perfect swimmer?
      -  he expended 4,000 Kc during workouts (he ate 12,000 Kc/day in training)
                  -  wide wing span of 79" (wider than he tall at 76")
                  -  inseam of only 32" (short legs) & long torso = rides high in water
size 14 'flippers'- 15 degree further ankle bend than most swimmers
                  -  wide shoulders, yet slender hips
  double jointed
elbows/knees = flex with an exaggerated range of motion
stroke volume 600 ml per vent./beat =  30 L/min (8 gal/min = 2x avg male)
  lactate levels = 5.6 mM/L is Ĺ that of many elite  swimmers.
                  -  and maybe most importantly excellent stroke mechanics.













   Much of vertebrate metabolic energy is used to maintain...  HOMEOSTASIS... 
i.e., regulating the internal 'cellular' environment of vertebrates.
                        maintaining a steady state internal constancy of condition
                                 in the face of a changing external environment

        PHYSIOLOGICAL COMPENSATION...  short term physiological adjustments 
              or adaptations to environmental changes, i.e.,
homeostatic compensation

        Internal "Milieu" - (Claude Bernard - Fr. 1880's)... observed the interstitial fluids 
        (the spaces between cells) which exchange nutrients with the blood
are very stable:


                          the Constancy of Human milieu includes...

                                    pH of blood           7.4      +   0.1
                                    body temp           37o C   +   1o C
                                    blood sugar         
[mg% - 100 mg/100ml blood]










Homeostatic Regulation:
       now let's look at some of the mechanisms that cells have evolved to maintain constancy
or the processes of P
hysiological Compensation.

        a Homeostatic Regulator
*  mechanism has 3 parts... (ex: a heating system)
                  1.   receptor ....         detects a change...                  thermometer
                  2.   controller ...        processes info...                       thermostat responds 
                  3.   effector .....         produces a response...            heater/chiller

* (not unlike signal transduction*)
  Examples of Homeostatic Regulation... (Physiological Compensation Mechanisms)

   1.  Temperature         

              Room temperature controllers - see
* -

              How a body warms/cools:       heat transfers from warmer body to a cooler one
                                                          body temperature thermoregulation

Human mechanism: in verts hypothalmus regulates
body temperature by linking
                                 nervous & endocrine system in homeostatic thermoregulation...
  fig 40.17*








pH regulation of the blood 
       pH 7.4  +  0.1      continuous blood pH below 7.0 can be fatal.
           Andromeda Strain
(TV-2008) - original story by Michael Crichton
                - virulent space microbe infects town's people...
                - microbe has crystalline structure & lacks DNA, RNA, & proteins,
                - all die by lethal blood clotting; growth curve of microbe = narrow pH range,
                - only 2 survived the microbe...  why
                          microbe grows only pH 7.35 - 7.45 (human blood pH range)
                          a crying baby - blows off CO2 - reduces blood acidity =
alkalosis  (pH > 7.45)
                       & a drunk (Sterno) - bleeding stomach ulcers - favors    = acidosis   (pH < 7.35)

carbonic* anhydrase - CO2 + H2O   <--CA-->   H2CO3   <--->  H+ + HCO3-  
                                                                                             carbonic acid                             

    Hemoglobin pick up H+ ions... buffering blood cells  &  CO exhalation

            buffer:     a substance, as HB & other proteins, that in solution tends to stabilize the
                           hydrogen-ion concentration by neutralizing, within limits, both acids and bases

                           if pH in blood cells drop [H+ ^] then carbonic anhydrase
                           HCO3-  +  H+ shifts ---> to   H2CO3  which dissociates & vice versa

Seawater Acidification*        oysters and seawater acidification video








Calcium homeostasis   (in blood - normal range is 9 to 11 mg%)

+2 is needed for nerve function, muscle contraction, blood clotting, etc. 
                      calcium regulation functions via
                      a common theme in homeostatic regulations...


                                thyroid makes -->   calcitonin hormone - lowers Ca levels
                                           causes Ca to be deposited into bone
                                           reduces intestinal absorption of Ca
                                           reduces Ca uptake by kidney


                               parathyroid -->  parathyroid hormone - raises Ca levels
                                          stimulates release Ca from bone
                                          increase Ca uptake by intestine & kidney

 orca         Calcium concentration is a delicate interplay between antagonistic hormones.  









 4. Blood Glucose balance -  (80-110mg/100ml)
             Pancreas makes
insulin and glucagon, which also function as antagonistic hormones

  How glucose homeostasis works*  and

                  How do insulin & glucagon function as signal molecules

                              Animation of Glucose Homeostasis*view@home    
(Am. Diabetes Assoc. & its diseases): 

            Insulin promotes cellular uptake of glucose into liver, muscle, and fat cells.
            Glucagon promotes the hydrolysis of stored glycogen in the liver and fat in adipose tissues.

    glucose level is a delicate interplay between antagonistic hormones (Insulin & Glucagon) 
    a paradigmKey Concepts*   
                   back          copyright c2021         
   next            Charles Mallery,    Biology 150, Department of Biology, U. of Miami,  Coral Gables, FL 33124

















' SKIP the Material Below and go to Major Vertebrate Tissues'
Chord'ates are characterized by a stiff (flexible) cord, notochord*, running dorsally.
 dorsal nerve cord - SPINAL CHORD - is a tube of nerve tissue, runs dorsal to notochord
  notochord - solid, flexible rod of cartilage provides internal support,
                                                                           runs from brain to tip of tail.

      in some chordates, the  notochord  is replaced by a BONY vertebrate column... 
making subphylum Vertebrata, a primary division of the phylum Chordata

            evolutionary innovations of CHORDATES:   [Cambrian Explosion]    
evolved 542-488 million years ago* - basic body plan of most animal phyla established:
                   bilateral symmetry        repetition of parts on opposite sides of an axis
    cephalization                 presence of a head
     notochord & spinal cord  dorsal cords of cartilage & nerve tissue
gill slits                         pair of openings through pharynx (vestigial in birds & mammals)
    tail                                present throughout life (vestigial in human embryos only)
    a fully lined body cavity thoracic and abdominal cavities lined by epithelia
    a complete gut tube        coelom - fluid cavity formed from mesoderm
    segmented development   in larva or embryo development myomeres flank notochord
                                              gives rise to muscles & bones











the VERTEBRAL members of chordate family have a number of similarities... 

         all have same basic body plan & same sort of organs [liver, kidney, pancreas] including:

           skeleton - with bony skull (cranium) surrounding brain    figure 49.26*
jointed bones - ball & socket, hinge, & pivot joints  
* surrounding a dorsal nerve cord
               coelom... internal tube which runs from mouth to anus (digestive system)
                              lined with mesoderm cells;  usually there are 2 cavities: 
                                     a) thoracic cavity
* -holds heart & lungs of verts
abdominal cavity
* -holds stomach, intestines, & liver   









      mammals... organism that maintain same body temperature regardless of environment,
                         have hair, and females that nurse their young.
      primates... vertebrate organisms with 5 grasping fingers/toes, eyes at front of head,
                        a large brain, & fingernails instead of claws.


   model vertebrate might be ourselves - the human...
- humans are  Endotherms...  warm blooded verts,      
                                      animals that regulates internal temperature at some constant value
Ectotherms...  cold blooded verts,  
                                         many vert animals
use environmental energy to regulate temp
                                       [ i.e., snakes, lizards, amphibians, fish, etc = ectotherms]

    but our human model is more distinct...

            some of our model human vertebrate's more unique characteristics include:
                           - humans have hair instead of scales & feathers, as in most verts,
                           - humans have a birthing process, instead of laying eggs,
                           - humans have at least 210 cell types in their body
[human histology]
















SMR - standard metabolic rate - ectotherms @ given temp
                      animal warms itself by absorbing heat from its surroundings


 Lance  Armstrong:
   - 6,500 Kc/d & 10,000 Kc/d for mountains
   - high % slow twitch (endurance muscle
   - long thigh bone = more force peddling
   - his heart is 1/3 larger than average,
       @ rest = 32 bpm  &  @ max = 200 bpm
          w stroke volume = 200ml (2x avg)
   - lactate levels of 6mM/L (normal = 12mM/L)

       Campbell 11e pgs: C40 (874-81), C41 (910). C42 (932), C44 (976-77 & 980), C45 (1009).
     Campbell 10e pgs: C40 (870-83), C41 (910), C42 (928-29; 942), C44 (971-76), C45 (1006).