Anatomy and Physiology in Kingdom Animalia
What is "Anatomy" and what is "Physiology"?
Anatomy refers to the study of the body plan, or structure, of animals. The basic method of this study is dissection.
Physiology refers to the study of the functions of the organs, organ systems and other parts of the body or living organism. Physiology looks at how these separate parts work together to maintain balance, and therefore survival.
In our lab sessions, we dissected three vertebrates: snake (reptile), shark (cartilaginous fish), and pig (mammal) and learned about two others (pigeon [bird] and mudpuppy [amphibian]). We dissected and explored the various organ systems of these organisms to observe how each one maintains homeostasis for the whole.
Anatomy refers to the study of the body plan, or structure, of animals. The basic method of this study is dissection.
Physiology refers to the study of the functions of the organs, organ systems and other parts of the body or living organism. Physiology looks at how these separate parts work together to maintain balance, and therefore survival.
In our lab sessions, we dissected three vertebrates: snake (reptile), shark (cartilaginous fish), and pig (mammal) and learned about two others (pigeon [bird] and mudpuppy [amphibian]). We dissected and explored the various organ systems of these organisms to observe how each one maintains homeostasis for the whole.
HOMEOSTASIS
Homeostasis is the body's way of maintaining stable internal conditions necessary for survival. Each organ system contributes to maintaining equilibrium.
The body uses negative feedback loops or positive feedback loops depending on the type of stimulus and necessary response.
In a positive feedback loop, the stimulus causes more of a certain response, whereas in a negative feedback loop, a stimulus causes a process to slow/halt.
There are 3 parts of a negative feedback loop:
Homeostasis is the body's way of maintaining stable internal conditions necessary for survival. Each organ system contributes to maintaining equilibrium.
The body uses negative feedback loops or positive feedback loops depending on the type of stimulus and necessary response.
In a positive feedback loop, the stimulus causes more of a certain response, whereas in a negative feedback loop, a stimulus causes a process to slow/halt.
There are 3 parts of a negative feedback loop:
- Sensors (receptor, e.g. skin)
- Control Center (Brain)
- Effectors (e.g. muscles, glands)
Kingdom Animalia
Some animals can maintain their body temperature via internal mechanisms - these organisms are endothermic.
Other animals depend on outside factors, such as sunlight or water temperature, to help them regulate their body temperature - these are called ectothermic.
> Phylum Chordata
> > Vertebrates:
Some animals can maintain their body temperature via internal mechanisms - these organisms are endothermic.
Other animals depend on outside factors, such as sunlight or water temperature, to help them regulate their body temperature - these are called ectothermic.
> Phylum Chordata
> > Vertebrates:
- Fish (ectothermic)
- Amphibians (ectothermic)
- Reptiles (ectothermic)
- Birds (endothermic)
- Mammals (endothermic)
Vertebrate Organ Systems
DIGESTIVE SYSTEM
The digestive system in a mammal (in this case a pig) consists of the mouth, pharynx, esophagus, stomach, intestines, liver, pancreas, spleen and anus.
The mouth is where food (energy) enters the body and is ground up by chewing with the teeth. Salivary glands are involved in breaking down the food, which then passes through the pharynx, then the esophagus, then to the stomach. The liver performs many essential functions related to digestion, metabolism, immunity, and the storage of nutrients. The pancreas secretes enzymes which pass into the small intestine. The waste products then exit the body through the anus.
There are some differences between the digestive systems of our five dissected animals. While the snake, pig, and pigeon all have a small and a large intestine, the mudpuppy and shark have only one intestine with a posterior and anterior section. The pigeon's stomach is different because it has two parts - the proventriculus and the gizzard, which grinds up hard foods.
CARDIOVASCULAR SYSTEM
The cardiovascular system consists of the heart, blood vessels and blood. This system is important for transporting nutrients, oxygen, carbon dioxide and other substances around the body. It maintains homeostasis by stabilizing body temperature and pH, and helps fight diseases.
The shark has a two-chambered heart, which means that oxygen dissolved in water enters through the gills and oxygenated blood and deoxygenated blood are mixed at all times. In the snake, we find a 3-chambered heart, which allows for partial separation of oxygenated blood and deoxygenated blood. In the mammal heart, there are 4 chambers which completely separate oxygenated blood from its counterpart. Both reptiles and mammals have lungs and lung capillaries, wherein the blood takes up oxygen.
The digestive system in a mammal (in this case a pig) consists of the mouth, pharynx, esophagus, stomach, intestines, liver, pancreas, spleen and anus.
The mouth is where food (energy) enters the body and is ground up by chewing with the teeth. Salivary glands are involved in breaking down the food, which then passes through the pharynx, then the esophagus, then to the stomach. The liver performs many essential functions related to digestion, metabolism, immunity, and the storage of nutrients. The pancreas secretes enzymes which pass into the small intestine. The waste products then exit the body through the anus.
There are some differences between the digestive systems of our five dissected animals. While the snake, pig, and pigeon all have a small and a large intestine, the mudpuppy and shark have only one intestine with a posterior and anterior section. The pigeon's stomach is different because it has two parts - the proventriculus and the gizzard, which grinds up hard foods.
CARDIOVASCULAR SYSTEM
The cardiovascular system consists of the heart, blood vessels and blood. This system is important for transporting nutrients, oxygen, carbon dioxide and other substances around the body. It maintains homeostasis by stabilizing body temperature and pH, and helps fight diseases.
The shark has a two-chambered heart, which means that oxygen dissolved in water enters through the gills and oxygenated blood and deoxygenated blood are mixed at all times. In the snake, we find a 3-chambered heart, which allows for partial separation of oxygenated blood and deoxygenated blood. In the mammal heart, there are 4 chambers which completely separate oxygenated blood from its counterpart. Both reptiles and mammals have lungs and lung capillaries, wherein the blood takes up oxygen.
URINARY SYSTEM
The urinary system's main function is to maintain the body's water balance. In mammals, the organs involved are the kidney, ureter, urinary bladder, and urethra. In sharks and some other fish, the body has little trouble maintaining water balance, because their concentration of dissolved substances is the same as in the water they live in (isotonic). Birds do not have a bladder, and therefore do not excrete urea like other animals. Instead they excrete uric acid - this difference helps them conserve water, which is essential because of their high body temperatures.
The kidneys are the major component in the urinary or excretory system, because they are responsible for maintaining the concentrations of water and salt in the body, excrete urea and regulate the blood's acidity. They do this by releasing unneeded substances in the waste product urea/urine.
REPRODUCTIVE SYSTEM
The purpose of the reproductive system is to produce gametes, or fertilized eggs, which then become offspring. The reproductive systems of the 5 animals dissected are very different.
Both fish and amphibians produce eggs which are fertilized externally. Reptiles reproduce by internal fertilization and lay their eggs on land. Birds reproduce by internal fertilization and lay hard shelled eggs on land. The eggs of reptiles, birds and mammals are all amniotic eggs, which contain a yolk for nutrients.
Mammals have internal fertilization but produce live young, which they feed and nurture with milk from mammary glands. The reproductive organs in mammals include the testes, penis, prostate gland and epididymis in males, and the ovaries, fallopian tube/oviduct, uterine horn, uterus and cervix in females.
In birds, most males have a papilla instead of a penis and females have only one ovary - each of these adaptations helps a bird stay light for flight. The female has an oviduct instead of the fallopian tube and uterus present in mammals.
The urinary system's main function is to maintain the body's water balance. In mammals, the organs involved are the kidney, ureter, urinary bladder, and urethra. In sharks and some other fish, the body has little trouble maintaining water balance, because their concentration of dissolved substances is the same as in the water they live in (isotonic). Birds do not have a bladder, and therefore do not excrete urea like other animals. Instead they excrete uric acid - this difference helps them conserve water, which is essential because of their high body temperatures.
The kidneys are the major component in the urinary or excretory system, because they are responsible for maintaining the concentrations of water and salt in the body, excrete urea and regulate the blood's acidity. They do this by releasing unneeded substances in the waste product urea/urine.
REPRODUCTIVE SYSTEM
The purpose of the reproductive system is to produce gametes, or fertilized eggs, which then become offspring. The reproductive systems of the 5 animals dissected are very different.
Both fish and amphibians produce eggs which are fertilized externally. Reptiles reproduce by internal fertilization and lay their eggs on land. Birds reproduce by internal fertilization and lay hard shelled eggs on land. The eggs of reptiles, birds and mammals are all amniotic eggs, which contain a yolk for nutrients.
Mammals have internal fertilization but produce live young, which they feed and nurture with milk from mammary glands. The reproductive organs in mammals include the testes, penis, prostate gland and epididymis in males, and the ovaries, fallopian tube/oviduct, uterine horn, uterus and cervix in females.
In birds, most males have a papilla instead of a penis and females have only one ovary - each of these adaptations helps a bird stay light for flight. The female has an oviduct instead of the fallopian tube and uterus present in mammals.
References
http://en.wikipedia.org/wiki/Anatomy
Illustration from Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/
http://en.wikibooks.org/wiki/Anatomy_and_Physiology_of_Animals/Urinary_System
http://en.wikibooks.org/wiki/Anatomy_and_Physiology_of_Animals/Reproductive_System
http://www.deanza.edu/faculty/mccauley/6a-labs-shark.htm
http://www.angelfire.com/oh5/ghsbiology/PigPicture.bmp
http://en.wikipedia.org/wiki/Anatomy
Illustration from Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/
http://en.wikibooks.org/wiki/Anatomy_and_Physiology_of_Animals/Urinary_System
http://en.wikibooks.org/wiki/Anatomy_and_Physiology_of_Animals/Reproductive_System
http://www.deanza.edu/faculty/mccauley/6a-labs-shark.htm
http://www.angelfire.com/oh5/ghsbiology/PigPicture.bmp