Midterm #1 Flashcards
(16 cards)
Lecture 1
What is Animal Physiology?
**The study of how animals “work” essentially.
The morphological, physiological and behavioral traits that enhance an organism’s ability to survive, grow and/or reproduce with respect to its biotic and abiotic environment**
How structures allow animals to function.
Lecture 1
What is meant by a comparative approach to animal physiology?
Remember humans are “just another animal”
**The study of the physiology of various organisms to elucidate the fundamental mechanisms, adaptations, and specializations that distinguish them from types of animals that do not live in those environments.
**
The study of knowing the different ways animals can solve problems like living in different environments, such as specific geese that can fly over Mount Everest, or closely related organisms to better understand the ability to thrive in specific habitats.
We can see the common problems and/or constraints because animals cannot be anything they want they need to obey physical and chemical laws
Lecture 1 Behavior
Ultimate vs
Proximate causes
Firefly
- Proximate causes is immediate stimulus and mechanism (how and what questions) What mechanism enables that organism to exhibit that behaviour? How is this behaviour triggered? How does this behaviour happen?
- Evolutionary explanation and/or significance How does this behavior contribute to its survival, reproduction and why has this behavior evolved? (why questions)
How an animal functions and what are the mechanisms
Signaling behavior ultimately to attract meals and/or mates
Lecture 2
What is phenotypic plasticity?
When a single genotype can look phenotypically two or more different ways.
Lecture 2
Physiological processes obey the laws of physics and chemistry. Provide an example that explains the role of chemistry and the role of physics in constraining animal physiology.
- Animals cannot be whatever they want, they still carry that genotype and/or genetic variation from the ancestors that came before them still within them.
- Physical properties of cell and tissues are linked to structure and function.
- The process of diffusion affects almost every physiological process (e.g Ficks’s Law).
- Molecular interactions are governed by chemical laws (Thermodynamics and kinetics)
- Electrical laws explain membrane function; especially excitable cells (nerves and muscles)
Excitable cells include neurons and skeletal muscle cells
Lecture 2
What is meant by an integrative approach to animal physiology? (physiology is integrative)
we do not just look at one level of biological organization right?
- Animal physiologists study phenomena at multiple levels of organization, from molecules to ecosystems.
- Animal pysiologists address both basic and applied questions.
***atoms>molecules>cells>tissues>organs>organ systems>organisms>populations>communities>ecosystems>biosphere - salmon and their leaps we would look at morphology, biochemistry, and biomechanics
gene>protein>cellular>tissue level…
Blood Pressure & Giraffes
adaptations
typical 120/75ish
It tells you the most pressure that comes out of your heart vs the pressure when your heart is relaxed.
In general for our brains to function they need 110/70 bp but for a girraffe that has to get blood much higher against gravity they need a blood pressure at their heart that is 220/180.
They also eat with their head down on the ground and by the physical laws they do not want all the blood pressure rushing down to their head and basically exploding their brain
Fick’s Law
How quickly something like sodium from one side of a membrane to another?
△C=concentratioin gradient
A=Surface Area
D=diffusion coefficient (permeability of a membrane temp)
x=Distance
Jnet=D△CA/x
Jnet is the rate of diffusion so if we want to increase (^) the rate of difussion then what can an animal do?
I can decrease x (distance) because if you want to make something bigger you want to decrease anything in the denominator
I can also ^ the surface area =A and/or change the concetratin gradient (anything on the numerator) and/or ^ permeability (more channels) =D
So if you can take away what you just diffused in, you can maintain a nice diffusion gradient because whatever moves across then moves out of the way. So what is sitting on one side of the membrane will notice not much there and will continue to diffuse across
concentration gradient, surface area, permeability of a membrane
thickness of the membrane =distance=x and determines diffusion coefficient =D
Biochemical & physiological patterns are influenced by body size
Scaling
Relationsip between an animal Physiology and its body size
* How does that physiological trait scale with body size
* The idea is as the body increases in its size, does the trait scale in direct proportion to how much body size has changed and/or does it scale disproportionately?
Organs proportion to human
Biochemical & physiological patterns are influenced by body size
Isometric Scaling
iso = same
Iso=same
- In direct proportion to its body size
- If bodiy size increases by 2 then there’s an increase of physiological trait by 2
- If you are 4x heavier then your heart size will be 4x heavier
Only a few things scale isometrically but heart size does!
Biochemical & physiological patterns are influenced by body size
Allometric Scaling
Galileo’s 1638
Galileo first saw that bones of larger animals were thicker than smaller animals.
* Ex: heart rate and metabolic rate
* Ex: heart rate of a small child compared to an adult’s heart rate, would be way faster
If body size doubles then whatever you are measuring does not double
It can increase slower but it will not double
Allometric Scaling example
Cat vs Elephant Bone structure
Elephant bones are much thicker (have larger cross sectional area) if both elephant and cat were the same size.
* If we were to cut the elephant bone in half it would be much wider than the cat’s even if both animals were the same size
* Strength of a bone is related to cross sectional area but weight of the bone that it must support is related to volume
* To undertsand allometric scaling, you need to understand that when an animal gets bigger the way its surface area increases is different then the way its volume increases
* Or say, if an animal gets bigger its surface area to volume ratio gets smaller
Explain the relationship between body mass and metabolic rate.
Who is a prominent figure in defining this relationship and what was this contribution?
UCD is very well known for this
Dr. Max Klieber
- He was the one that began to understand, allometric scaling and metabolic rate
- He measured metabolic rate in everything from a mouse all the way to an elephant aka the mouse and elephant curve
- It basically showed that allometrically scaled to the power of ¾ not ⅔
- Because if something scales isometrically it would scale to the power of one 2/2 3/3 4/4
physiological processes are regulated
Claude Bernard
- Discoverd glycogen, hemaglobin carries oxygen and he discovered horomones. he discovered nerves can regulate blood flow
- He was the first to describe the concept milieu interieur aka homeostasis
- That animals can maintain an environment inside distinct to environment outside of them
- Invented experimental physiology
WAS THE FIRST TO DESCRIBE THE CONCEPT OF HOMEOSTASIS
Homeostasis
Claude Bernard was the first to describe that animals can maintain an environment inside distinct/independent to environment outside of them
For example measuring our body temperature right now it would be warmer than the room which is about 22 degrees celsius and that is because we regulate our body temperature so that it is distinct from our natural environment because we are endotherms.
Physiological processes are usually regulated: homeostasis
Walter Canon
coined term: Homeostasis
the idea that animals (we) have physiological processes that we coordinate and regulate internal processes like internal temperature or saltiness in our blood, osomality in our blood, blood pressure, the amount of sodium/cholride we have to maintain as constant as we can
stepping outside when its cold your body will beginto initiate a number of Processes to get the body back to where it needs to be (either generate heat or shed heat)
Polar bears and homeostasis
