Intro to Animal diversity, form and function, and homeostasis Flashcards
What are the defining characteristics of animals?
animals are multicellular heterotrophs that feed by ingestion, have extra cellular matrix’s and collagen, a blastula stage of development, hox genes, distinct germ layers, symmetry, muscles, nervous system, and senses.
Would you consider a sponge to be an animal, explain. Be sure to include a description of the
characters of both sponges and animals in your explanation.
I would consider a sponge not to be an animal. Sponges are more like sisters to animals, because they lack key characteristics, such as germ layers, symmetry, muscles, and a nervous system. These are all very important defining characteristics of animals. The argument that they are animals is based in the characteristics sponges share with animals, including differentiated cell types, apoptosis, collagen, recognition of cell from no self, regulation of the cell cycle and growth, gene regulation, and developed signaling. However, their lack of the other defining characteristics clearly distinguishes them apart from animals.
Explain why cnidarians do not require a circulatory system
Cnidarians have a thin body wall and a large surface area so that it can easily diffuse oxygen directly from their surroundings. There is no need for a circulatory system.
List the defining characters of Cnidarians
Cnidarians have radial symmetry, two germ layers, stinging tentacles with cnidocytes, and there are 4 main lineages (hydrozoans, cubazoans, scyphozoans, and anthrozoans)
List the defining characters of arthropods
Arthropods have a hard exoskeleton made of chitin, jointed limbs, and compound eyes
List the defining characters of mollusks
mollusks have a mantle used for excretion and breathing, and have radula (except bivalves)
List the defining characters of chordates
chordates include animals with backbones, a muscular post-anal tail, pharyngeal slits/ gills in fish, dorsal nerve cord, notochord
What’s the average body temperature of humans?
around 98 degrees F
97.7-99.6F
Define homeostasis
homeostasis is maintaining an internal balance, or an ordered, nearly-constant internal environment different from one’s surroundings
(an organisms ability to resist change and maintain its set points, or the relatively constant internal environment)
Explain why there are no perfectly adapted animals (include a trade-offs and provide examples)
There are no perfectly adapted animals because there are always trade-offs to adaptations. For example, many animals such as birds and fish trade off speed for agility, and vice versa. Jumping spiders have large forward-facing eyes for hunting, where web-spinning spiders have smaller eyes because they don’t have to actively hunt when their web catches their prey.
What’s the difference between acclimation and adaptation, explain why you cannot adapt to
your environment. (provide examples)
adaptation is a long term adjustment that occurs over generations in a population as a result of genetic changes due to environmental factors. Acclimation is a short-term, more immediate change on an individual level to environmental changes and is dependent on the genetics of an organism (like the production of melanin)
Name the four types of tissues in the human body
Connective, epithelial, muscle, and nervous tissue
Which types of tissues have excitable membranes?
Nervous and muscle tissues have excitable membranes
Animals living in cold water face several challenges: How could they maintain membrane fluidity in cold temperatures? Explain
An animal living in cold water could maintain membrane fluidity by having short, unsaturated fatty acids. This would allow for more membrane fluidity than long, saturated fatty acids because they are less viscous and more susceptible to changes in kinetic energy. The short, poly unsaturated fatty acids would allow the membrane to be more fluid and not solidify due to the bends/kinks in the membrane
Animals living in cold water face several challenges: What would happen if their membranes became too viscous or rigid?
If the membrane became too viscous or rigid, this would impact cell function and risk cell death?
how is special fluid connective tissue different from the other types of connective tissue?
Special fluid connective tissue (=blood cells) do not contain fiber and transport materials including oxygen throughout the body and play an important part in our immune system.
Other connective tissues do not transport fluid and are generally used for structural support (like dense connective tissue = tendons and ligaments that attach muscles to bones and connect bones together) (bones = connective tissue)
In class I described bilateral animals as a “tube”, What did I mean by that (Hint: The digestive
tract)
Bilateral animals are just a tube as in their digestive tract functions ultimately as one long tube that travels through the Boyd and connects the mouth to the anus
Define metabolism
the sum of all chemical reactions in an organism
Define metabolic rate
the overall rate of energy consumption by an individual
Determine base metabolic rate
The rate at which an animal consumes oxygen while at rest
Explain why an elephant has a higher whole-animal metabolic rate than a shrew, but a shrew has a much higher mass-specific metabolic rate
An elephant has a much larger mass than shrew, and therefore will have a higher whole-animal metabolic rate than a shrew because it has a much larger body and therefore consumes more energy. However, a shrew has a higher mass-specific metabolic rate because when compared to the elephant on an even scale, the shrew has a higher MR per gram. Smaller animals lose more heat (larger surface area to total volume ratio), and therefore require more energy and consume nearly their body weight in a day (where an elephant comes only a fraction of their weight) to maintain their body temp
Based on the laws of thermodynamics, are animals open or closed systems?
Animals would be considered open systems because they exchange energy with their surroundings by consuming and releasing energy by doing work. This follows the laws of thermodynamics because E cannot be created nor destroyed and as it is transferred and used is loses some of its usability (giving off heat, poop, nitrogenous waste)