BIO 181 FINAL

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

Define the term "natural selection" and indicate role that environment plays in this process.

"differential success in the reproduction of different phenotypes resulting from the interaction of organisms with their environment". The environment can dictate which traits get passed on, such as the body size in birds in warm vs. cold climates. Fatter birds evolved in the colder climates and smaller birds evolved in warmer climates because it is advantageous to be fatter to stay warm in the cold climates and the same type of reasoning applies for the warmer climates and the smaller birds.

1. Describe the basic structure and function of simple arthropod eyes; how are they better than the eyecups of flatworms?

"simple eyes." Like eyecups, they have a central group of light-sensitive cells that transmit signals to the brain via a nerve. Unlike eyecups, they have a clear material above the sensory cells that focuses light into the eye, thus acting like a lens. This makes the eye very sensitive to changes in light intensity and also forms an image that the brain can interpret.

Give two examples of endocrine organs that act independently of the nervous system and explain what controls their secretion.

1) Insulin secretion by the pancreas is independent of the nervous system, but the brain "steps in" if glucose levels are too low. 2) Hormone secretion by the parathyroid glands to maintain calcium homeostasis in the blood is a good example of endocrine action independent of the nervous system.

1. Describe the characteristics that enable amphibians (as compared to fish) to live on land. name 4

1) supporting its weight without the buoyancy of water, 2) preventing desiccation from water loss through the skin, 3) acquiring sufficient oxygen from the air, 4) producing eggs that can survive on land. Amphibians never completely solved these problems and, with a few exceptions, must spend at least some of their time in or near the water. Amphibians do have a stronger skeleton than fish as well as four limbs that can support their weight on land. They do not have a protective skin covering to prevent water loss, but do secrete mucous to moisten the skin surface. They have lungs for air-breathing, but these lungs are small and cannot acquire sufficient oxygen to support life. Thus amphibians must also absorb oxygen through their skin--one reason why the skin is thin and must be kept moist. Amphibian eggs are not much different from those of fish and must develop in the water.

Explain the structure and function of a reflex arc.

A sensory neuron in the leg senses a tap on the knee and sends this information to the spinal cord. Within the spinal cord, an interneuron receives the signal and transmits it to the dendrites of an appropriate motor neuron which sends a signal along its axon to a muscle in the leg. This loop is called a reflex arc. It enables the leg to jerk in response to the hammer before the sensation has reached the brain. Other interneurons in the spinal cord do send the information to the brain, but by the time the brain interprets the message, the leg has already moved. Note that the dendrite of the sensory neuron and axon of the motor neuron are very long; they extend from the central part of the body into the leg

1. Know the approximate time (number of years ago) that the first life forms appeared on earth and indicate two geological or climate factors that have greatly influenced biodiversity during the long period of life on earth.

3.5 billion years ago life appeared. Continental drift and glaciation.

1. Name and describe the group of algae that gave rise to the first plants.

A group of green algae called the charophyceans. have chlorphyll contained within membrane-bound structures, the chloroplasts. Plants originated from multicellular, branching charophyceans These algae have more features in common with plants than the simple algae, including sexual reproduction that utilizes large eggs and smaller sperm.

1. Define the term "phylogenetic tree" and indicate the significance of branch points in a tree.

A phylogenetic tree is a hypothesis that depicts the evolutionary relationships among groups of organisms; in detailed phylogenetic trees, branch points indicate when new species diverged from a common ancestor.

Know what is meant by the term "ecological succession"; how do primary succession and secondary succession differ?

After an area is cleared out, it is repopulated with other organisms that eventually mature. Primary succession takes place in places without soil and takes decades. Primary succession occurs in areas that have no soil. An example is succession on newly formed sand dunes at the edge of oceans or lakes. Sand is not true soil and must first be colonized by dune-building grasses. When the dunes are stabilized and soil begins to accumulate through decomposition of dead grass and animal inhabitants, pines invade the area. Eventually there is adequate soil and soil nutrients for other tree species to grow. At lake Michigan, black oak becomes the dominant species. Note that in primary succession, the community takes a long time to reach maturity. Secondary succession occurs in disturbed areas that retain soil. Since soil does not have to be established and some community members are still present, secondary succession occurs more rapidly than primary succession. One example occurs after a forest fire. This photograph shows Yellowstone national park just after the major fire of 1988. One year after the fire, the forest looked like this. Secondary succession is well underway. A variety of plants, different from those in the former forest, now cover the ground. Secondary succession is also seen in agricultural land that has been abandoned. Here we see a cornfield during the first two years after agriculture ceased. During the first year, only old corn stalks are seen, but by the second year, wild grasses have invaded the area. By the fifth year sedges have joined the grasses, and by the tenth year there are goldenrod plants, blackberry, and juniper trees. After 20 years, birch and maple trees are present and the community is approaching maturity.

Regarding the coelom, be able to: describe its location in the body using annelids as an example indicate its general functions list which of the phyla contain animals that have a coelom

All except porifera, cnidarian and platyhelminthes have a coelom These worms have a distinct tube-within-a-tube body plan. The innermost tube is a 1-way digestive tract that begins at the mouth and ends at the anus and is covered by a layer of muscle. The tube is suspended within the fluid-filled coelom. The outermost tube is the body wall which consists of two layers of muscle and a covering of epidermis. In the molluscs, the coelom was reduced to a cavity surrounding the heart and parts of the digestive tract. In the annelids, and most remaining phyla, the coelom is larger and plays a greater role in animal form and function. In the case of earthworms, the coelom provides room for the digestive tract to expand and contract as it moves food from mouth to anus. As in molluscs, the coelom provides space for a beating heart (actually 5 pulsating blood vessels in earthworms). The coelom also functions as a hydrostatic skeleton in annelids. Fluid pressure within this cavity gives rigidity to the soft body of the worm and is utilized in locomotion, as you learned in a recent laboratory assignment. Note also the relatively large excretory structures (metanephridia) that lie within the coelom.

1. Indicate the difference between allopatric and sympatric speciation and give an example of each.

Allopatric speciation - A mode of speciation induced when the ancestral population becomes segregated by a geographic barrier. Example: The isthmus of panama did not always exist, and there was once unbroken ocean between North and South America. When the land bridge formed, it cut through many populations of marine organisms, including shrimp. As a result, there are now different species of shrimp on the Atlantic vs. Pacific side of the isthmus. Sympatric speciation - A mode of speciation occurring as a result of a radical change in the genome of a subpopulation, reproductively isolating the subpopulation from the parent population. Example: The apple maggot fly appears to be undergoing sympatric speciation, because it originally laid its eggs on the hawthorn plant but when apple trees were introduced some started laying on the apple trees. The offspring prefer to lay eggs and fertilize wherever they were born so gene flow is restricted and sympatric speciation can occur.

Describe the function(s) of chemosensory cells; how wide spread are they in living organisms?

Almost all animals have chemosensory cells that perceive specific molecules within the air or water.

Name the three types of waste products that result from protein metabolism and indicate the groups of animals that secrete each type.

Ammonia - Aquatic animals Urea - Mammals, many adult amphibians Uric Acid - Insect, birds, many reptiles

Compare the general structure of the nervous system in the following animals; which of them have a large brain? Annelids, arthropods, cephalopod molluscs, vertebrates

Annelids - Annelids have a single or double nerve cord that runs along the ventral side of the body from head to tail. A small ganglion is present in each segment and a pair of large ganglia are located in the head region. arthropods - Arthropods have a nervous system similar to annelids, but with a large and complex brain. As shown in this fly, a ventral nerve cord with ganglia runs down the body and gives of branches to the periphery. cephalopod molluscs - The cephalopod molluscs are very active and have a larger concentration of neurons in the head. This nervous structure has several subdivisions that control different bodily functions and is complex enough to constitute a brain. Note that two pairs of ventral nerve cords with ganglia are also present. vertebrates - Vertebrate animals also have a centrally located nerve cord, but it is on the dorsal side of the body and is surrounded by bony vertebrae that form the vertebral column. As you know, the nerve cord has a hollow center and is called the spinal cord. It connects to a large, complex brain that is contained within the skull. Cranial nerves emerge from the brain, and paired spinal nerves connect to the spinal cord along its entire length. These nerves branch to provide nervous connections to the skin, organs, and muscles of the body.

1. Be able to explain how land plants have changed earth's environment during the last 500 million years and how this, in turn, affected the evolution of plants.

At the beginning of this time, carbon dioxide levels were much higher than today, oxygen levels were lower, and the land was barren with little or no soil. As the bryophytes colonized land, they developed some decay resistant tissues, no doubt to combat attack by prokaryotes and fungi. When these plants died, much of their mass did not decay and the carbon locked in their tissues was not returned to the atmosphere. This may have begun the decrease in atmospheric carbon dioxide as indicated on the chart. When vascular plants arose, the lignin in their vascular tissue was even more resistant to decay. So much of the carbon dioxide that the plants removed from the air during photosynthesis remained in dead plant tissues and was eventually buried as plant activities produced soil. Note the steep drop in carbon dioxide levels as vascular plants became widespread. This was the Carboniferous period and was also the time of highest atmospheric oxygen content. As you know, much of the plant matter buried then is now coal. Also note that seed plants arrived after the drop in carbon dioxide level, thus were not responsible for it. As carbon dioxide decreased, so did global temperatures, since carbon dioxide traps heat via the "greenhouse" effect. Cool air holds less moisture than warm air, so the land became drier. This resulted in the proliferation of the seed plants which were better adapted to dry conditions that the seedless, vascular plants. So the ferns and their relatives limited their future by becoming so successful that they altered earth's climate.

1. What is the "Three Domain" concept?; which types of organism are found in each Domain?

Bacteria, Archaea and Eukarya. Eukarya and Archaea are more closely related. Domain Archaea - prokaryotic, no nuclear membrane, distinct biochemistry and RNA markers from bacteria, possess unique ancient evolutionary history for which they are considered some of the oldest species of organisms on Earth Domain Bacteria - prokaryotic, consists of prokaryotic cells possessing primarily diacyl glycerol diester lipids in their membranes and bacterial rRNA, no nuclear membrane, traditionally classified as bacteria. Domain Eukarya - eukaryotes, organisms that contain a membrane-bound nucleus. Much larger cell size. Now broke up into 8 kingdoms

1. Describe two major adaptations that allow the majority of arthropods to live on land.

Breathing air and laying eggs that are able to handle arid environments. unlike those of most aquatic invertebrates, insects eggs contain a large amount of yolk and are adapted to survive in the absence of external water. The large yolk stores allow the embryo to grow into a large larva, or even achieve the adult body form, before hatching. The eggs are covered by a tough, waxy shell that allows passage of oxygen but not water. Hence the moisture within the yolk is sufficient for development of the embryo in a dry, terrestrial environment.

1. Know the three main categories of nutrients (carbohydrates, lipids, proteins) and their major roles in the human body.

Carbohydrates are the main energy source for vertebrates and the main source of carbon. Lipids can also be metabolized for energy, but are also required to construct cell membranes. When lipids are stored as fat, they can serve as a thermal insulator. Proteins are extremely important, since they provide the amino acids for synthesis of new proteins. This is especially important for building and maintaining muscle. In the case of humans, there are 8 amino acids that cannot be made. It is essential that the diet contain these amino acids. Meat is a good source of protein and contains all 20 amino acids.

Indicate which brain regions are folded and the purpose of the folds.

Cerebral cortex. Cerebral mass and the degree of folding are associated with more complex behaviors, since there are more neurons to process and interpret information.

In which animals did neurosecretion probably originate?

Cnidarians such as the hydra have a nerve net that controls body movements. The nerve net is composed of neurons connected to one another throughout the body and the tentacles of the animal. Some of these neurons also secrete hormones into the surrounding tissues. As shown here, the cell body of the neuron produces the hormones which travel down the axon and are secreted at its tip. These neurohormones then diffuse into tissues and regulate processes such as growth, reproduction, and regeneration of missing body parts if the animal is injured. Thus neurosecretion and hormonal regulation exists in the simplest animals with tissues that are alive today.

1. Define the terms "competitive exclusion" and "ecological niche", then indicate how they are related (why does competitive exclusion not occur in every case where species share the same food resource?).

Competitive exclusion - Strong competition between species can result in elimination of one of the species from the local area. An ecological niche is defined as the sum total of a species' use of the resources in its environment. Besides food includes other factors such as its preferred living space and specific behavior patterns. Competitive exclusion doesn't always occur because they might occupy slightly different niches even if there is some overlap.

1. Explain the advantages of a 1-way digestive tract; name two phyla of animals that have such a digestive tract and two phyla of animals that do not.

Digested nutrients are absorbed by cells that line the intestine and undigested waste leaves via the anus. Note that in all animals of the bilateria lineage, except for flatworms, digestion is mainly extracellular. This is an advantage of sequential digestion along a lengthy, digestive tract. Chordata and annelids have a one-way digestive tract. Porifera and Cnidarians do not

In the female sexual cycle of humans, explain how changing levels of FSH, LH, estradiol, and progesterone affect reproduction.

FSH and LH stimulate the secretion of male and female hormones from the ovaries and testes in addition to regulating the production of sperm and eggs, and TSH stimulates the thyroid gland to make and release thyroid hormones. The last two hormones on the list, growth hormone and prolactin, do not act on other endocrine organs, but have direct effects on growth, metabolism, and milk production following pregnancy.

1. Explain the difference between a plant epiphyte and a plant parasite; what does each gain from its host?

Epiphytes are plants that grow on other plants, especially on trees. They do not receive any food or water from the host plant, and do no harm. The epiphyte benefits by a firm support at a high location where sunlight and water are more plentiful. Epiphytes are especially abundant in tropical rain forests as shown in this photograph. All of the plants attached to the tree trunk are harmless epiphytes. Note how the epiphytes differ from parasitic plants, like mistletoe. Epiphyte gets access to sunlight. Examples of plant parasite is Mistletoe takes water and minerals from its host. Rafflesia Arnoldii is an angiosperm that lives on a vine. It is an angiosperm.

1. Be able to compare a logistic growth curve to that of an exponential growth curve; what is carrying capacity and how does it relate to a logistic curve?

Exponential is an ideal growth rate where the population keeps doubling in size. As time goes on the increase faster and faster. It increases quicker. It is the top part of the S curve. Carrying capacity is when the exponential growth levels off, it is the cap. The maximum population that can be sustained in a given area

1. Be able to compare the general heart structure and pattern of blood flow in fish vs. mammals; how does blood get to and from the lungs of a mammal?

Fish have a 2-chambered heart consisting of one atrium and one ventricle. Veins enter the atrium and blood moves to the ventricle, then out into arteries. Blood next passes though the gills where it absorbs oxygen. This is indicated by a change in color from blue (no oxygen) to red (full of oxygen). The oxygenated blood travels through capillaries in the body where it gives up oxygen to the surrounding cells, then is returned to the heart. Note that blood makes a single circuit from heart to body and back to the heart. In terrestrial vertebrates, the heart is divided and blood passes through it twice: once from heart to lungs to heart, and then from heart to body to heart. Birds and mammals have a 4-chambered heart with two atria and two ventricles. In all vertebrate animals, the ventricles contract strongly to drive blood through the system. Note that in the air-breathing vertebrates, oxygen-rich blood from the lungs enters the left atrium while oxygen-poor blood from body enters the right atrium. In mammals, blood coming from the lungs is kept separate from that coming from the body since the ventricle has two chambers. Thus oxygen-poor blood pumped from the right ventricle goes to the lungs to be oxygenated and oxygen-rich blood pumped from the left ventricle goes to the body.

1. Explain how genetic drift differs from natural selection; how does population size affect genetic drift?

Genetic drift are changes in microevolution that happen due to chance, such as one random extra cold winter that kills off a bunch of bees and so there are very few that pollinate, and the ones that do only pollinate red ones. Since this is a one off event and not a consistent environmental pressure it is considered genetic drift instead of natural selection. Natural selection is when traits are selected for due to the environmental conditions that are simply random. If birds eat bright colored beatles instead of brown ones of the same species year after, then the beatles will evolve the brownish trait and we would call this natural selection. However, if one year a stampede of elephants comes through and by chance kills off more colored beatles, say 70/30, then even though that will effect the outcome of the next generation of beatles we wouldn't say it is natural selection we would say that it is genetic drift, because it was just chance that 70 percent of crushed beatles were brightly colored. Genetic drift has more of an impact on small populations. Given the smaller number of individuals it is easier for a trait to start dominate and get fixed in the population. Larger populations are resistant to genetic drift, because it is hard for the trait to get fixed due to the larger number of individuals with the opposing trait. The chance of flipping a coin four times and it landing on heads each time wouldn't be too surprising. However, if you flipped a coin four hundred times and it landed on heads each time you would be amazed and worried that it was a trick coin.

1. Explain the difference between gradual evolution and punctuated equilibrium.

Gradual evolution is the idea that organisms evolved gradually over long periods of time such as the horse with its longer legs and feet turning to hooves. Punctuated equilibrium is when something evolves to changes in the environment, but once the environment stabilizes and the organism has adapted to it, it quits evolving and flat lines until new environmental conditions show up.

1. Compare the gravity/motion sensors of large crustaceans and vertebrate animals.

Gravity sensors are call statocysts. The statocyst is a small sphere lined with cells that bear cilia. The hollow center of the structure contains a small particle about the size of a sand grain. As the orientation of the crayfish head changes, the inner particle moves and presses against different groups of cilia. This pressure is due to gravity. When the information is passed to the brain by sensory neurons, the animal knows which direction is down. All vertebrates, including fish, have an organ of balance and motion detection that is a more elaborate version of a statolith. It is embedded within the skull and consists of a fluid-filled sac containing tiny particles called otoliths plus three semicircular canals that are also filled with fluid. The sac and canals are lined with hair cells similar to those in the lateral line system. The sac detects the downward force of gravity as the otoliths press against hair cells.

Name the two defining characteristics of mammals.

Hair - Keep warmth, porcupine quills, less hair in walrus Milk Production from mammary glands

Describe the location and specific functions of chemosensory cells in insects and mammals.

Insects have them on their mouth parts, legs and antennae. Insects have cells on the proboscis that taste the chemicals in potential food. They also have bristles on the legs and body that sense chemicals within the air or liquids. Antannae in moths is used to detect pheromones secreted by females to indicate mating. Mammals have olfactory receptors within the nasal cavity and taste buds on the tongue. Air binds to moist mucous so that molecules can be captures. Molecules bind to the tips of olfactory cells which then signal to the olfactory bulb, which is part of the brain. Taste buds detect molecules at the tip of their cells and send information to the brain.

1. Compare photoreception in the euglena and the planarian.

In Euglena, a tiny light-sensitive spot is present near the base of the flagella. It senses the presence or absence of light and assists the euglena in locating a suitable place in its aqueous environment. The planarian has a pair of eyecups on the upper surface of its head. By detecting light, it is able to move to dark places, more suitable for hiding. Each eyecup consists of a group of light-sensitive cells called photoreceptors. They are surrounded on one side by a layer of cells that contain pigment, which absorbs light coming from that direction. Thus light can only be detected on one side of the cup. The two eyecups face in opposite directions so that the direction of light can always be determined. Light waves hitting the photoreceptors creates a signal that is passed to the anterior ganglion by connecting neurons. Thus the free-living flatworms can sense both the direction and intensity of light and respond appropriately. As you might expect, the parasitic flatworms lack eyes, which are not needed in the dark body of a host.

1. Describe the factors that limit primary production in terrestrial vs. aquatic ecosystems.

In terrestrial environments availability of water is the largest factor, followed by temp, followed by nutrients. Availability of water and nutrients as well as the temperature. Water is the most important. Temperature helps because it increases/decreases metabolism. There is a positive correlation between evapotranspiration and primary productivity. Nutrients can limit growth. In marshes, adding nitrogen doubled growth. Adding phosphorous on top of that increased it again. Just adding phosphorous alone didn't increase growth. Nutrients can be a limiting factor in growth. Since there is plenty of water in aquatic environments it is light penetration that is the biggest factor. Photosynthesis can only take place in about 50-100 meters. Nutrients play a big role in primary production in aquatic environments. Upwelling zones in marine environments have a lot of primary producers and fish because nitrogen from the ocean floor is brought up. Nitrogen and phosphorous are the two most important compounds.

1. Describe several ways that flowers are pollinated and several ways that seeds are dispersed in angiosperm plants.

Insects, bats. Flowers are shaped to fit their mouths, tongues, beaks. Wind dispersal. Burrs can stick to animals. Pass through digestive track after eating fruit containing seeds.

1. Indicate ways in which bird and mammalian lungs are more efficient than amphibian lungs in acquiring oxygen; which group has the most efficient method of ventilation?

Lung ventilation is much more efficient in mammals than in amphibians. We will use a human to illustrate how mammals move air in and out of their lungs. The lungs are enclosed in a portion of the body cavity. The floor of the lung cavity is formed by the diaphragm, a sheet of muscle that divides the lung cavity from the abdomen. During inhalation, the muscles between the ribs (intercostals) contract. This lifts the chest and expands the lung cavity. At the same time, the diaphragm flattens to further expand the cavity. The resulting negative pressure causes air to flow into the lungs. Upon exhalation, the rib muscles relax and the diaphragm returns to its dome shape. The decrease in size of the cavity around the lungs forces air out of the lungs.. So unlike amphibians which push air into the lungs, mammals pull air in by creating a vacuum. Reptiles also utilize negative pressure for ventilation, but they lack a diaphragm, so can only expand the lung cavity through use of rib muscles. Birds have a truly unique system of ventilation that is the most efficient of any vertebrate animal. The lungs of a bird are surrounded by air sacs. These sacs expand and contract to move air continuously through the lungs in a one-way direction. This is different from other vertebrate lungs in which air moves in during inhalation and out during exhalation. As air flows through the small tubes (parabronchi) within a lung, oxygen is absorbed.

1. Describe the relationship between the anterior lobe of the pituitary and the brain.

Many endocrine organs are under control of the anterior pituitary gland which secretes several hormones when stimulated by the hypothalamus of the brain. The anterior lobe of the pituitary secretes six major hormones. t is important to note that all of these secretions by the pituitary are controlled by the hypothalamus. Neurons within the hypothalamus secrete neurohormones into the blood. These "releasing factors" travel a short distance to the anterior lobe of the pituitary where each triggers the secretion of a specific pituitary hormone. Some hypothalamic neurons utilize neurosecretion to release hormones into small blood vessels of the brain. A short network of vessels (portal veins) carry these neurohormones to the nearby anterior pituitary where they leave the blood and bind to pituitary cells. This causes the pituitary to secrete specific hormones into another bed of capillaries that transport the hormones into the general blood stream and thus to their target organs throughout the body.

Indicate the location and function of mechoreceptors in mammalian skin.

Mechanoreceptors that provide a sense of touch (vibrations and other sensations) are also widespread; mammalian skin can sense light touch, pressure, pain, and temperature.

The flatworms are the simplest animal group to develop mesoderm and cephalization. Indicate the advantages of these features, as illustrated by flatworms.

Mesoderm allows tissues to organize into organs and even connect in organ systems, if an animal tends to "lead" with the same end all the time, it will move most efficiently if both sides match. A preferred front end also leads to cephalization, a concentration of senses and processors in the front. Most flatworms have a central digestive cavity similar to that of the Cnidarians. It serves the functions of both digestion and circulation and has only one opening to the outside. In planarians the cavity is branched.

1. Explain the difference between microevolution and macroevolution.

Microevolution happens on a shorter timescale, just a few generations. Macroevolution is over large timescales and is used to build phylogenetic trees. This would show the relationship between plants and animals whereas microevolution would just show the slight changes in a species within a few generations.

1. Describe the structure and function of the arthropod exoskeleton and indicate why molting is necessary.

Molting allows growth The cuticle of arthropods is a type of exoskeleton. Like the skeleton of a mammal, it functions both to support the body and move body parts. Imagine that you are in a suit of armor and have lost every bone in your body. Now attach your muscles to the armor and you have an exoskeleton that supports the body and is movable. The arthropod exoskeleton is jointed and numerous small muscles provide a wide range of movements that are not possible in worms, which have no skeletal support and whose muscles form continuous sheets or bands.

1. Compare the closed circulatory system of annelids (such as the earthworm) to the open circulatory system of arthropods; which type of system is found in vertebrate animals?

Most animals that have a thicker body, including a coelom, utilize blood and blood vessels for transport. The earthworm is a good example. It has one large vessel that runs along the ventral side of the body and carries blood to the tip of the tail. Another large vessel is located dorsally and carries blood toward the head end of the worm. Lateral branches connect these vessels in each segment; beds of small blood vessels are the sites where oxygen and nutrients are delivered to cells and where waste products are collected. Oxygen diffuses into this circulatory system through the wet skin which is why the earthworm must live in moist places. There are 5 connecting vessels in the anterior end of the worm that are large and pulsate. These contracting vessels serve as "hearts" to move blood through the system. Because blood never leaves the blood vessels, the worm is said to have a closed circulatory system. Such a system is found in the majority of animals. Arthropods also distribute nutrients and collect metabolic wastes by means of a circulatory system. However, the blood of these animals leaves the blood vessels at some point and enters the body cavity which is called a hemocoel because it contains blood. This is demonstrated in the diagram of an insect. A single heart is present which contracts to pump blood into two large vessels, one running into the head and the other into the abdomen. Small vessels branch off at regular intervals. They are open-ended, so this is where blood enters the hemocoel. Eventually blood is returned to the heart through small openings in the heart wall. This is called an open circulatory system.

1. Be able to give some examples of how both prey and predator species use mimicry and explain how this is beneficial to them.

Moths mimic wasps to avoid being eaten. Spiders resemble ants so they can get close to their prey. King snake mimics the coral snake so that predators think it is poisonous.

1. Name several animal groups that have neurosecretion as their main source of hormones, and two animal groups that also have endocrine organs.

Neurosecretion also provides the main source of hormones in flatworms, nematodes, and annelids. neurosecretion is found in almost all invertebrate animals. Sponges, that lack a nervous system, are the only exception. In the more primitive groups of bilaterally symmetrical animals, such as flatworms, nematodes, and annelids, neurosecretion provides the main source of hormones. As animals increased in complexity, endocrine organs separate from the nervous system took over much of the endocrine function, but many interactions with neurohormones and the brain were retained. Arthropods and vertebrates have evolved endocrine organs for hormone secretion.

1. Indicate two ways that nitrogen fixation occurs in nature and explain why is this important for plants.

Nitrogen fixing bacteria, fertilizer/organic material and lightning storms. Nitrogen can be a limiting factor of growth for plants because it is a macronutrient for plants.

1. List the 4 characteristics of chordate animals and give the function of each; what additional feature is found in vertebrate animals?

Notochord - a rod-like structure that runs along the dorsal side of the body. It is stiff enough to provide support for the body, yet flexible enough to bend. the notochord is composed of large, fluid-filled cells that bulge due to internal water pressure. They are held in place by two sheaths of tissue. Thus, the stiffness of the notochord results from hydrostatic pressure, not from the presence of hard minerals as are found in shells or bone. dorsal nerve cord - located just above the notochord. It expands somewhat at the anterior end to become a primitive brain. This forms the central nervous system of all chordate animals. pharynx with slits - The pharynx is the first part of the digestive tract. In the primitive chordates, it functions as a filter-feeding device; water is taken in through the mouth and expelled through pharyngeal slits. Small food particles are retained by the pharynx and passed to the intestine for digestion. post-anal tail - extension of the body that runs past the anal opening. Vertebrates have a back bone

What is the cause of diabetes type 1 vs. diabetes type 2?

One form of diabetes occurs when the body's immune system mistakes the beta cells for pathogens and destroys them. This results in very low insulin levels. Cells elsewhere in the body cannot absorb sufficient glucose from the blood stream and blood glucose levels rise so high that glucose is excreted into the urine. Symptoms of diabetes include fatigue, frequent urination, excessive thirst, and unusual weight loss. This type of diabetes unusually begins in childhood and is called diabetes type 1. A second type of diabetes is more prevalent in adults and is called diabetes 2. It is initiated by a failure of cells throughout the body to take up adequate amounts of glucose from the blood stream. This is called "insulin resistance". It has several causes, including genetic factors, but is often brought on by obesity. Since blood glucose levels remain high at the onset of this condition, the pancreas secretes insulin continuously. Eventually the islet cells "wear out" and insulin levels drop to very low levels making the diabetic condition worse.

1. The sponges are primitive animals that lack a nervous system, but can they respond to stimuli? (If so, how?)

Openings into the sponge are formed by specialized cells that extend through the wall creating a pore. These cells can contract very slowly to close the pores. Such a response is usually due to changes in water quality. For example, an increase in water borne silt would stimulate pore closure thus protecting the sponge from becoming clogged with particulate matter.

Be able to describe the difference between parasitism, mutualism, and commensalism (and to give an example of each).

Parasitism one species benefits at the others detriment. Mutualism both species benefit. Commensalism one species benefits without harming the other one. Parasitism - A tick on a moose is and ectoparasite. Mutualism - Bee pollinating for a flower and getting nectar. Algae also forms mutualistic interactions with various cnidarians. Commensalism - Bee Orchid - Bee isn't benefited or harmed but orchid pollinates. Ox stirring up ground that provides food for the birds, but doesn't harm or benefit them.

1. Name and describe the 3 levels of organization that constitute the science of ecology.

Population, community, ecosystem. The same levels of organization apply to other living things. The red sunfish shown above is an organism. A group of these fish living in the same location constitutes a population. The sunfish live in a pond with many other plants, animals, and single-celled organisms. This interacting group of living organisms is a community. Add the environment around the pond and physical factors (such as soil, wind, sunlight, and rainfall) and you have an ecosystem.

1. Know the main characteristics of the following phyla of animals, and give examples of animals within each group: Porifera, Cnidaria, Platyhelminthes, Mollusca, Annelida, Arthropoda, Chordata

Porifera - Sponges, Cellular, Lacks tissues and organs Cnidaria - Hydra, Anemones, Jellyfish. Tissue, lack organs, radial, two germ layers. Platyhelmithes - Flatworms. Has organs, cephalization, bilateral symmetry. No coelom Mollusca - Snails, clams, squid. Organs, bilateral symmetry, reduced coelom Annelida - Segmented worms. Cephalization, organs, bilateral, coelom Arthropoda - Insects, spiders, crustaceans. Organs, bilateral, reduced coelom. Cephalization Chordata (including the vertebrates) - Birds, humans. Organs, bilateral, cephalization, coelom.

1. Compare the structure and function of the nervous system in a radially symmetrical hydra to the bilaterally symmetrical flatworms (planaria).

Radially symmetrical animals have a diffuse nervous system with no central control. have a network of neurons that connect cells within both layers of their body. This type of system is called a "nerve net". Has a localized response. Bilaterally summetrical flatworms. sensory structures are larger and more numerous on the head end of the animal. This is accompanied by a centralization of the nervous system with addition of some integrative function. The flatworm nervous system consists of a nerve cord on each side of the body with cross connections like rungs in a ladder. The nerve cords connect with nerve nets that connect to muscles and internal sensory cells. At the anterior end, the nerve cords join two large ganglia. A ganglion is a concentration of neurons. Has a centralized response.

♣ How is diabetes type 2 related to obesity? ♣ Do genetic defects play a role in diabetes?

Since blood glucose levels remain high at the onset of this condition, the pancreas secretes insulin continuously. Eventually the islet cells "wear out" and insulin levels drop to very low levels making the diabetic condition worse. Yes.

Know what constitutes the gametophyte generation in gymnosperms and angiosperms Describe the basic structure and function of a pollen grain and an ovule, and indicate where they are formed in gymnosperms and angiosperms.

Spore production in gymnosperms is found in male and female cones the pistil is the female reproductive structure found in flowers, and consists of the stigma, style, and ovary. Stamen produces pollen (male gametes) In gymnosperms the gametophyte forms in the cone. The female gametophyte forms the equivalent of an archegonium containing an egg. The gametophyte stores large amounts of carbohydrates, fats and proteins provided by the pine tree. The resulting structure is called an ovule; it is essentially the female gametophyte with eggs and stored food. The sporangium forms protective coats around the ovule. They will become the seed coat when the ovule becomes a seed. the male gametophytes have developed from microspores. They become pollen grains, are released from the male cone, and drift in the wind. If a pollen grain lands on a female cone, it produces sperm and a tube that grows into the ovule. Sperm pass through the tube and fertilize the eggs within the ovule. The resulting zygote develops into an embryo and the ovule is now a seed. It is released from the female cone and carried by the wind to a new location. Describe the basic structure and function of a pollen grain and an ovule, and indicate where they are formed in gymnosperms and angiosperms. In angiosperms ovaries are part of the pistel within the flower. Pollen grains are formed on the anthers of the stamen. They are the male gametes that are used to fertilize eggs. The ovule is found inside the ovary and is the female gamete. In gymnosperms these are developed on cones.

Describe how plants regulate water loss; what are guard cells and stomata?

Stomata is a tiny opening in the leaf that allows for gas exchange (taking in carbon dioxide). The guard cells can close the pores if water is limiting to prevent water loss by evaporation from the inside of the leaf. When water is limiting, the guard cells become flaccid and move together, thus closing the pore.

1. Describe structure and function of the lateral line system in fish; where are the hair cells located?

The "hair cells" that sense water movement are housed within shallow grooves just below the skin surface which are in contact with the water through small pores. These grooves are called lateral lines. The cells have long, rigid cilia and are clustered beneath a gelatinous substance, the cupula. When water flows through the lateral line, it bends the cupula which stimulates the cilia of the hair cells. The message is transmitted to the brain by sensory neurons. This helps a fish detect currents, wave action, or the movements of nearby fish.

1. Indicate the three steps that are common to the function of most excretory systems and the significance of each.

The basic filtration system used by most invertebrates is diagrammed here. The main structure is a tubule that begins in the coelom and ends in a pore on the external surface of the animal. Water containing metabolic waste and salts enters one end of the tubule. This is the filtration step. The tubule may be open at this end to pull in fluid from the coelom or, as shown here, it may absorb fluid from the blood stream. In either case, the fluid moves through the tubule toward the external opening at the opposite end. Along the way two important processes occur. First, much of the water, salts, and any nutrients in the fluid are reabsorbed. This means that energy is used to transport them out of the fluid and back into the coelom or blood stream. In this way water is conserved and necessary salts and other molecules are reclaimed by the body before they are excreted. Finally, other salts may be secreted into the tubule to make fine adjustments to the final salt and water balance in the blood or coelomic fluid. When the fluid within the tubule passes through the external pore, it has been excreted. This basic system is widespread and is even used, with some modifications, in vertebrate animals.

1. Indicate how energy changes as it is transferred from one trophic level to the next; what is a pyramid of production?

The percentage of energy assimilated by an organism that is converted into biomass. Take the amount of joules consumed, subtract what is used for metabolism and wasted in feces. The remaining number is what was converted to biomass. Divide this number by the initial amount consumed and then multiply by a hundred. Pyramids of production are based on trophic levels starting with primary producers and accounts for energy transfer. Since this starts the food chain, it will always be the largest at the bottom and smallest at top given energy lost. Since the top depends on the bottom it will never have more energy than the bottom.

1. Describe the basic structure of the vertebrate eye; what other animal group has the same type of eye, and how is it better than the simple eye of most invertebrates?

The eye of vertebrates has a single lens that can focus light to produce a very clear image on the retina. The lens is suspended within the eye by small muscles. These muscles can contract and relax to change the shape of the lens as needed to focus incoming light precisely on the retina. The retina lines the inner surface of the eye and contains several layers of neurons in addition to the photoreceptor cells. The photoreceptors are of two kinds: the rods are sensitive to dim light and form a black-and-white image, whereas the cones are require a brighter light, but detect color. Information from the rods and cones are conducted to the retina surface and from there out the large optic nerve to the brain. Because there are so many photoreceptors in the retina, the brain is able to form a very detailed image. Also note that the lens is located behind the iris which can open and close to control the amount of light that enters the eye. ability of the lens to focus on objects that are near or distant. cephalopod mollusks have the same eye structure

Name the 3 groups of living mammals and indicate how reproduction differs in these groups.

The monotremes lay eggs, the marsupials nurse offspring in a pouch, the eutherian mammals have the most efficient placenta during gestation.

1. Know the basic structure and function of the mycelium and where it is located relative to fruiting bodies of the multi-cellular fungi.

Underground, a network of fine filaments called hyphae. The hyphal network is called a mycelium. It spreads through the soil and absorbs nutrients from organic matter left by decaying plants and animals. many fungal species reproduce sexually by forming a structure called a fruiting body. This structure is produced above ground by the fusion of many hyphae.

Explain how the function of the posterior lobe of the pituitary gland differs from that of the anterior lobe (how does its relationship to the hypothalamus differ?).

The posterior pituitary also secretes hormones, but by a different mechanism; antidiuretic hormone (ADH) is a major secretion of this pituitary lobe. There is a direct connection between the brain and this lobe of the pituitary. Note that several nerve tracts emerge from the hypothalamus and enter the posterior lobe. Clusters of neuronal cell bodies within the hypothalamus synthesize hormones which pass down the nerve tracts and enter the pituitary where they are stored for release when needed. This is quite different from the way in which the anterior lobe functions. Note that the same hormone produced by neurosecretion is released by the posterior lobe, whereas the anterior lobe responds to neurosecretions by producing new hormones.You learned about one hormone released by the posterior pituitary in the previous topic on salt and water balance. Recall that the hypothalamus contains osmoreceptors that detect the amount of water in the bloodstream. If the blood volume is too low, these receptors signal the hypothalamic neurons to secrete ADH, the antidiuretic hormone. ADH accumulates within the posterior pituitary and is released into the blood stream. It travels to the kidneys and elicits water resorption from the kidney collecting ducts. Thus the volume of urine is decreased and water is returned to the blood stream.

1. What is binomial nomenclature?

The two-part latinized name of a species which was first put into practice by Carl Linnaeus and consists of a capitalized and italicized Genus name and a lower case and italicized species name.

1. Compare the structure and function of xylem vs. phloem in flowering plants.

The xylem consists of cells joined end-to-end to form long tubes. The flowering plants have two types of xylem tubes, tracheal tubes and vessels. Tracheid cells are relatively thin and tapered at both ends. Both the cross walls between cells along the tube and the side walls between adjacent cells have pits. These pits are small and prevent air bubbles within the tube from passing to adjacent tracheids. Vessels have a larger diameter. The end walls between vessel cells along the tube have large slits and do not impede the movement of water up the tube. The pits in the side wall vessels are also larger than those of tracheids. These features allow faster water conduction in flowering plants as compared to gymnosperms that have only tracheids, but the large pits of vessels do allow the passage of air bubbles. Thus embolism, caused when air blocks the flow of water, can be a problem. Embolisms tend to form within vessels after freeze-thaw cycles, draught, or physical damage. Since flowering plants have both tracheids and vessels, the tracheal tubes provide a "safety valve" when embolism occurs within the vessels. Note that the walls of both tracheids and vessels are strengthened by lignin. The more xylem present, the stronger the root or stem. Phloem is vascular tissue designed to conduct fluids containing organic molecules. Its main function is to supply sugars to parts of the plant that do not photosynthesize, such as roots, seeds, flowers and fruit. Whereas the tracheal tubes and vessels of xylem are composed of dead cells, the cells of phloem are alive. The phloem tubes are made of cells lined up end-to-end with large pores in the cross walls. Phloem tubes are always found adjacent to xylem. Together they are called vascular bundles.

Know which mammals have the largest brain in proportion to their body size.

Unusually large in dolphins and humans

1. Describe the basic structure and function of insect compound eyes.

They are composed of a large number of individual units called ommatidia. Each ommatidium has a lens that focuses light on to underlying light-sensitive (photoreceptor) cells. Nerves carry information from each ommatidium to the brain where the information is interpreted as an image. However, the main function of compound eyes is probably to detect motion. The eyes bulge out from the sides of the head allowing a wide range of vision. Slight changes in light, due to motion, are immediately detected allowing the animal to respond quickly. As we all known from experience, it is difficult to swat a fly or step on a roach.

1. For each of the above endocrine organs, indicate how hormone secretion is affected by the pituitary gland and explain how feedback loops work.

Thyroid Gland - Normal negative feedback: Pituitiary sends TSH to adrenal gland, thyroid sends normal T3 T4. Reduced negative feedback: Pituitiary sends excess TSH and thyroid sends low T3 T4. Adrenal gland - Releasing hormone for pituitary ACTH. The ACTH then travels to the adrenal gland where it initiates synthesis and secretion of cortisol. Elevated blood levels of cortisol act on both the hypothalamus and anterior pituitary to reduce the release of CRH and ACTH. Hence negative feedback loops eventually return cortisol blood levels to the normal, unstressed, level. Ovaries - Ovarian hormone secretion is controlled by the anterior pituitary. FSH secretion by the pituitary stimulates follicles to grow and decreases slightly as they become larger. LH secretion remains low until a follicle has matured; LH secretion then spikes to a high level which induces ovulation. This LH spike also initiates conversion of the empty follicle into a corpus luteum, thus producing increased progesterone secretion. As estradiol (estrogen) levels rise from growing follicles, they exert a positive feedback on the hypothalamus. The hypothalamus signals the pituitary to release a large amount of LH and ovulation occurs at the time of maximal follicle size. As the follicles grow, they also produce an inhibitory hormone that reduces FSH secretion by the pituitary. During the latter phase of the cycle, high progesterone levels exert negative feedback on both the hypothalamus and pituitary causing FSH and LH secretion to decrease. If no pregnancy occurs, the corpus luteum degenerates, progesterone levels drop, and the pituitary can again secrete its hormones. If there is a successful pregnancy, the corpus luteum remains large and no sexual cycling occurs until after the baby is born. Testes - The same pituitary hormones that regulate female hormone production also control functions of the testes. Under the influence of the hypothalamus, the anterior pituitary secretes LH which travels to the testes and stimulates Leydig cells to secrete testosterone. Meanwhile, FSH from the pituitary stimulates the functions of Sertoli cells and sperm are produced. Some of the testosterone enters the bloodstream and promotes development and maintenance of male secondary sex characteristics such as bread growth and a muscular body. High testosterone blood levels exert negative feedback on the hypothalamus and pituitary to reduce LH and FSH production. As in other feedback loops, this maintains the circulating hormone testosterone at appropriate levels.

Indicate some advantages of producing seeds

Tough outer coating to help survive in harsh. conditions. Large food supply in the seed for the embryo. Can be dispersed by wind or animals. Increases genetic diversity by cross fertilization

Know the main parts of a seed -

Tough shell, endosperm which is food, embryo

. In mammals that have only a single sexual cycle per year, indicate how the nervous system and endocrine organs interact to control seasonal breeding.

Triggered by Spring in Elk, when there is more food available and it is warmer.

Explain how neurosecretion and endocrine organs work together to regulate metamorphosis in moths.

Two hormones control these molts: An endocrine organ within the body of the caterpillar (the prothoracic gland) secretes pulses of the hormone ecdysone, while the brain secretes a neurohormone called juvenile hormone. As long as juvenile hormone remains at high levels, each pulse of ecdysone elicits a molt. As the caterpillar reaches a large size, levels of juvenile hormone drop. The next pulse of ecdysone elicits pupa formation and the metamorphosis of the caterpillar into a moth. Note also that secretion of ecdysone from its endocrine organ is under control of the brain. Vertebrate animals also utilize both neurosecretion and endocrine organs in many regulatory functions

Indicate 3 ways in which protists can move and give a specific example of each.

Using Flagellum to move, these are long appendages. The flagellated protist, eugleonoid uses this. Cilliated protist, these are much smaller (hair-like) that help movement. Paramicium is an example of using cilia. Protist with pseudopods, this is what amoeba usually use. When they are on a substrate they use cytoplasmic streaming.

Describe additional features that account for the diversity and success of modern mammals.

Variety of teeth for different eating styles. Different limbs, such as hooves for running, hand for digging, opposable thumb in apes for handling things, dolphins formed flippers for swimming, flying in bats

1. Describe several ways that the seedless, vascular plants (such as ferns) are better adapted for life on land than the bryophytes (such as moss).

Vascular plants have roots, leaves and stems. All vascular plants are better adapted to land than bryophytes since their roots can absorb water and minerals from the soil and these needed materials are transported throughout the plant by tracheal vessels. An ample water supply plus the strength of the tracheal vessels allows these plants to grow taller than the bryophytes. There are two additional adaptations to land that relate to water conservation: 1) the leaves of vascular plants are coated by a waxy cuticle that prevents water loss by evaporation from the leaf surface, and 2) stomata are present on leaves to regulate gas exchange and retard water loss. The leaves must take in carbon dioxide and emit oxygen during photosynthesis. The stomata are openings that allow passage of gases. The stomata can open and close; if the plant is losing too much water or if the soil is dry, the stomata close to retard water loss. The sporophyte has become much bigger and independent from the gametophyte. the sporophyte plant can grow much larger and withstand more environmental stress than bryophytes.

Relative to trophic levels in a community, be able to: explain what is meant by a food chain

Who eats who starting at the top: tertiary consumer, secondary consumer, primary consumer, primary producer

Study Final Essay Questions by writing actually typing answers

You need to do this!

1. How is a species defined by the "biological concept"?

ability of the population to interbreed. Problem is that lions and breed with tigers in captivity, but they don't do this in nature. Even if they did, ligers are sterile and can't pass on their genes. So interbreeding isn't quite accurate.

1. Compare the ear structure of amphibians and mammals; in what ways is the mammalian ear better at detecting sound?

amphibians retained the inner ear structure of fish for balance and sensing head motions, but this structure acquired a short region for sensing vibrations in the fluid surrounding it which could be transmitted to the brain as sound. To allow these fluid vibrations to mimic those in the air (sound waves), a middle ear cavity developed. Within this cavity resides a long, thin bone. One end of the bone is attached to a thin, skin region called the tympanic membrane. The other end of the bone presses against the side of the inner ear chamber. Sound waves cause the tympanic membrane to vibrate. The attached bone then vibrates at the same frequencies and transmits the vibrations to the fluid of the inner ear. the human ear, utilizes a 3-part system. The outer ear channels sound waves into an auditory canal that leads to an internally located tympanic membrane, now called the ear drum. The middle ear cavity has the same function as in amphibians, but there are three bones (instead of one) to transmit vibrations to the inner ear. The third middle ear bone, called the stapes, rests against a thin part of the inner ear called the oval window. Vibrations of the stapes causes the oval window to vibrate at the same frequencies, and these vibrations are transmitted to the fluid within the cochlea of the inner ear. The cochlea is the region that detects vibrations and sends information to the brain. It is much larger than that of amphibians. The cochlea is a long, fluid-filled tube that is coiled in order to fit within the inner ear cavity of the skull. The major advance in hearing is due to development of the cochlea. Sound waves with high frequency are detected by cells in the upper part of the cochlea, and those at lower frequencies are detected farther down the cochlea. Each group of hair cells within the cochlea respond to a different frequency. Thus mammals can distinguish a wide range of sound, from high to low notes. Due to the channeling effect of the outer ear and the amplification of vibrations as they travel through the middle ear, mammals have sensitive hearing (can hear soft as well as loud sounds).

Describe the location within the brain and function(s) of the following brain regions: cerebral hemispheres - Forebrain hypothalamus - cerebellum - medulla oblongata -

cerebral hemispheres - Forebrain. responsible for all higher order functions; the cerebral surface area is increased by foldings. higher order brain functions, including integration of sensory information, generation of commands to skeletal muscles, learning, memory, and the ability to reason. hypothalamus - the hypothalamus develops from the central area. One of the most important functions of the hypothalamus is to link the nervous system to the endocrine system via the pituitary gland cerebellum - Coordinate/control multiple muscular contractions in a way that maintains balance and carries out the commands of the cerebrum. Thus the cerebellum allows us to walk without falling down to coordinate hand-eye movements, and perform complex activities such as typing or shooting a basketball. medulla oblongata - It coordinates many basic reflexes and controls homeostatic processes such as heart rate, breathing, swallowing, and overall function of the digestive tract. Note that there is some overlap between the functions of the hypothalamus and the medulla, but whereas the hypothalamus acts through control of hormone secretion, the medulla acts through nerves of the autonomic nervous system.

Relative to the mammalian nervous system, distinguish between the following: dendrite and axon of a neuron: sensory neuron, motor neuron, and interneuron - central nervous system and peripheral nervous system -

dendrite and axon of a neuron: The cells that receive and conduct signals through the nervous system are called neurons. Each neuron has the three parts: cell body, axon and dendrite. Long, thin structures called dendrites extend from each end of the cell body. They are extensions of the plasma membrane and contain a small amount of cytoplasm. Dendrites receive signals and conduct them toward the cell body. The axon conducts signals away from the cell body to another neuron or muscle fiber. sensory neuron, motor neuron, and interneuron - Sensory: part of the peripheral nervous system. They receive signals from the environment and transmit this information to the central nervous system. Motor: relay information from the central nervous system to the periphery. In the mouse example, a motor neuron with its cell body in the spinal cord transmits a command to a muscle in the leg. Interneuron: Located entirely within the spinal cord and brain. They relay signals from one neuron to another. Memory and reasoning ability depend upon interneurons. central nervous system and peripheral nervous system - CNS: consists of the brain and spinal cord which are composed of tightly packed neurons and supporting cells. PNS - composed of nerves that emerge from the brain and spinal cord.

What are the symptoms of diabetes?

fatigue, frequent urination, excessive thirst, and unusual weight loss.

1. Distinguish between a shared, primitive character vs. a shared, derived character in a cladogram.

ferns, conifers and flowering plants all have vascular tissue--a trait that they share with their common ancestor A. The vascular tissue trait is thus a shared, primitive character. On the other hand, conifers and flowering plants have seeds, but ferns do not. This trait is called a shared, derived character since it is not possessed by ancestor A.

Be able to name the four lobes of the cerebrum and indicate the major functions of each.

frontal lobe - is responsible for initiation of voluntary movements, decision making, controlling impulses, and exhibiting judgment during conscious thought. The parietal lobe - receives and interprets sensory information from the eyes and the skin. It also plays an important role in spatial awareness (using visual cues to orient the body in space). The occipital lobe - controls many aspects of vision and color recognition temporal lobe - is required for language, hearing, and some types of memory.

1. Indicate how fungi are of benefit to human life regarding: General health of the ecosystem, Production of pharmaceuticals and Baking

general health of the ecosystem - Provides food, decomposes the cellulose in wood so is crucial to forest systems. Form mycorrhiza, which many plants require . production of pharmaceuticals - antibiotics such as penicillin. Cyclosporine used to prevent the rejection of transplanted organs. Baking - alcoholic fermentation of yeast is used to make dough rise. beer and wine production - alcoholic fermentation of yeast is used to make dough rise. Yeast produces alcohol in wine and beer.

1. Indicate a beneficial effect of bacteria on: Human health, Cycles in nature, Products produced by biotechnology

human health - anaerobic bacteria in the intestine. This makes up our gut flora. Most of these are beneficial and even necessary. They digest fibers and carbohydrates. The end product is small fatty acids which can be digested. They produce vitamins. Keep away pathogens. Eat yogurt, kombucha or other probiotics in the morning! cycles in nature - Used for chemical recycling e.g. compost farms, treating sewage (bacteria remove about 50% of waste) and cleaning oil spills (bioremediation). products produced by biotechnology - Used to make antibiotics (use bacteria that secrete chemicals that kill other bacteria), plastics, drugs, food additives.

distinguish between primary producers, primary consumers, and consumers at higher trophic levels

primary producers start the food chain (like plants), primary consumers are herbivores, other consumers are carnivores.

1. Know, in general terms, the types of organisms found in the following groups; how do eukaryotic organisms differ from the prokaryotes? Prokaryotes, Protista, Fungi, Plants, Animals

prokaryotes - bacteria Protista - algae, slime molds Fungi - mushrooms Plants - trees, flowers, ferns animals - snakes, bears, insects, crustaceans Eukaryotic cells are larger. They both have dna, ribosomes and a cell membrane. Eukaryotic cells have mitochondria, endoplasmic reticulum. Prokaryotes don't have a membrane bound nucleus

1. Explain how the following factors relate to the success of prokaryotes as a group: Reproducing by binary fission, Producing Endospores

reproducing by binary fission - Rapid reproduction allows prokaryotes to spread quickly across the environment producing endospores - Endospores are produced which can stay viable for a very long time, this means if conditions become unfavorable they won't all die off. In the article the guy was claiming to jump start dna that had been preserved in amber. Hard to know if his cultures were due to contamination or not.

1. Distinguish between the function of the nervous system and the endocrine system; what is neurosecretion?

the nervous system consists of neurons like those shown here. Neurons have long processes that conduct electrical signals along their length. Some neurons carry information from sense organs to the brain and spinal cord, while others stimulate muscle contraction or secretion from various glands. The command for muscle contraction or secretion can be initiated by the brain or spinal cord. The conducting processes of many neurons are typically bundled together to form nerves. Hormones comprise the second type of control system. Hormones are chemical signals that are secreted by endocrine organs or tissues located throughout the body. Certain neurons can also secrete hormones by a process called neurosecretion. Most hormones enter the blood stream and are transported to cells in other locations where they act. The receiving cells are called "target cells" and have receptors on their surfaces that bind the hormone. Thus only cells in specific parts of the body can respond to specific hormones. Like neurons, certain hormones can increase the speed of muscle contraction or stimulate glands to secrete their products. Both neurons and hormones can also slow down muscle contraction and inhibit secretion depending on which neurons are active and which types of hormones are released.

For each of the following endocrine organs, indicate the hormone(s) that it produces and the effect of each hormone on the body: Thyroid gland, Adrenal cortex, Ovaries, Testes

thyroid gland - Regulates the body's metabolic rate and provides feedback to the hypothalamus regarding blood levels of thyroid hormones. thyroxine and triiodothyronine. hypothyroid individual becomes lethargic and develops thick lips and a puffy face. Can develop a goiter. opposite condition is called hyperthyroidism. It is characterized by elevated metabolic rate, bulging eyes, anxiety, and heat intolerance. adrenal cortex - The cortex region of the adrenal gland secretes glucocorticoids that respond to stress and exert feedback by inhibiting secretion of ACTH. make a class of hormones known as glucocorticoids, named for their effects on glucose metabolism. The major human glucocorticoid is cortisol. lucocorticoids suppress some functions of the immune system, especially inflammation. Thus they have been used to treat allergic reactions to bee stings and hive outbreaks. ovaries - The ovaries of female mammals secrete the hormones estradiol and progesterone that are crucial for reproduction; sexual cycling is initiated by FSH and LH from the anterior pituitary. As the follicles continue to grow, estradiol secretion increases and remains much higher than progesterone secretion. Following ovulation, the follicle is converted into a corpus luteum which secretes some estradiol, but much higher levels of progesterone. Note that estradiol (called estrogen here) is highest at the time of ovulation (ovulatory phase). Secretion of progesterone by the corpus luteum then rises and is highest at about a week after ovulation. When estradiol and progesterone are at their lowest levels (shown as day 7 in the graph), the uterine lining is thin. As estrogen levels rise the lining thickens. The following increase in progesterone causes the lining to become even thicker and filled with blood vessels. The uterus can now undergo pregnancy. If no pregnancy occurs, hormone levels drop and the thickened uterine lining is discarded, returning to its thin status. FSH secretion by the pituitary stimulates follicles to grow and decreases slightly as they become larger. LH secretion remains low until a follicle has matured; LH secretion then spikes to a high level which induces ovulation. This LH spike also initiates conversion of the empty follicle into a corpus luteum, thus producing increased progesterone secretion. As estradiol (estrogen) levels rise from growing follicles, they exert a positive feedback on the hypothalamus. high progesterone levels exert negative feedback on both the hypothalamus and pituitary causing FSH and LH secretion to decrease. I testes - secrete the hormone required for sperm production and are regulated by the same pituitary hormones (FSH and LH) Testosterone. Tubules (called Leydig cells) secrete testosterone which diffuses into the tubule and stimulates sperm production. Testosterone produces beard and muscular growth.


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