Bio Exam 3

Describe HAART and how it has changed HIV from a once fatal diagnosis to a managed disease. (lecture, 14.3)

-highly active antiretroviral therapy -involves the simultaneous use of multiple drugs to block HIV reproduction (interferes with each stage of the life cycle of HIV)

Describe the relationship between HIV and AIDS. (lecture, 14.3)

-AIDS is the end stage of the HIV infection -the symptoms you experience when you lose T-cells are called AIDS

Explain why the Irish Potato famine occurred and its consequences to people in Ireland. (lecture, 17.3, 18.2)

-Blight (a type of fungus) hits potatoes, 1845 -people of Ireland were highly dependent on potatoes -resulted in widespread famine and a million people were killed.

Describe the physiology of addiction and why addiction is now viewed as a treatable brain disorder. (lecture, 11.1)

-Drug enhances the amount of dopamine in the synapses --> Increased dopamine results in increased feelings of pleasure-repeated use of a drug --> receptor cells shutdown-The natural capacity to produce dopamine in the reward system is reduced --> Addict must take higher amounts of the drug to produce the same dopamine "high"

Describe the origin of HIV and how it spread to the entire world. (lecture)

-HIV in humans is thought to have originated in Africa -HIV is a mutated version of a chimpanzee virus, known as simian immunodeficiency virus, which probably made the species-jump through contact with infected blood while handling bush meat.

Describe HIV and how it is spread from person to person. (14.3)

-infects cells of the immune system—most notably, the helper T cells (aka CD4 cells)-infected person's overall T -cell count drops.-virus-mutated version of a chimpanzee virus, known as simian immunodeficiency virus-HIV is transmitted through contact with infected blood and bodily fluids-HIV is transmitted by anal sex (anal sex is the riskiest type of sex for transmission of HIV)-HIV is transmitted by vaginal sex-HIV is rarely transmitted by oral sex

Describe the history of the first vaccine (Smallpox). (lecture, 12.3)

-Smallpox vaccine: Injection of live Vaccinia viruses that cause antibodies and memory cells that work against smallpox viruses-The World Health Organization (WHO) began a vaccination campaign against smallpox in the 1960's-Areas afflicted with smallpox declined during the 60s and 70s-Smallpox was eradicated in the wild by 1977-Smallpox still stored in two government labs in Russia and the US-antibodies that defeated cowpox will also bind to and defeat smallpox

Describe the reasons why some people mistakenly thought there might be a connection between vaccines and autism. (lecture, 12.3)

-Some parents of children with autism say the first noticed signs of autism a few days, weeks or months after receiving the MMR vaccine (normally given at 12 to 15 months of age). They assume this shows cause and effect. -An article was published in the Lancet by Andrew Wakefield concluding that autism may be caused by the MMR vaccine

Describe why a reduction in a person's Helper T cell count would reduce the effectiveness of their immune system. (lecture, 12.2, 14.3)

-When your T-cell count gets below a certain threshold, you begin to experience a range of symptoms called AIDS -lacks a sufficient number of T cells to fight off the infecting microbe

Describe how GMO's may help farmers provide sufficient food for the human population. (article, 18.2)

-allows farmers to grow crops without using pesticides, or at least using far fewer. -created to capitalize on a favorable condition or characteristic whose genetic sequence can be inserted into the genome of the modified organism.

Describe how skeletal muscles pull bones into place and work in antagonistic pairs. (11.2)

-are most often connected to your bones, under voluntary control by your somatic nervous system, and allow for movement of your body. -Muscles are cells that can physically move, by contracting and relaxing, in response to a stimulus-connected by tendons. - work in pairs -one muscle (or group of muscles) pulls the bone one way and another muscle or group pulls the bone back in the opposite direction.

Describe the consequences of DDT on animals such as bald eagles. (lecture, 18.2)

-caused the eagle's egg shells to be too thin and the chicks died before hatching

Explain why feelings of pleasure caused by the "reward pathway" would have provided an evolutionary advantage. (11.1, 13.1)

-dopamine serves as a signal that the action promotes survival or reproduction -ex. we like to have sex b/c sex makes us feel pleasure and causes the release of dopamine --> sex is essential to survival because of reproduction -dopamine reinforces behaviors (sex, eating) essential to our survival

Explain why an estimated 25% increase in population will require a doubling of food production. (article, 18.2)

-feed more people -spread of prosperity across the world, especially in China and India, is driving an increased demand for meat, eggs, and dairy, boosting pressure to grow more corn and soybeans to feed more cattle, pigs, and chickens.

Describe food webs and explain the consequences of disrupting a food web. (18.1, 18.3)

-graphical representation of the interactions between autotrophs and heterotrophs within an ecological community -describes the relationship between producers and consumers -if one animal disappears from a food web, the consumers that preyed on that animal and the prey that animal consumed would suffer (predator will lose its food source and decrease, the prey will increase because it is no longer being eaten)

Describe a monoculture and compare and contrast its risks and benefits. (lecture, 17.3, 18.2)

-have a field that contains only one plant -if a disease infects the crop, then the entire crop could be destroyed -more difficult to grow and more vulnerable to diseases and pests in unknown land

Describe DDT and when and why it was first used. (lecture, 18.2)

-invented in the 1940s and viewed as miracle for farmers and safe -insecticides (dichloro-diphenyl-trichloroethane) -remarkable power to kill insects, particularly body lice -first used to kill lice during WWI to stop the spread of typhus (which is spread by body lice) -pests soon become resistant

Describe how the demand for more food may affect rainforests. (article, 18.2)

-may cut down rainforests in order to convert the land into farming land (to utilize the rain water) -increase in greenhouse gases because trees are usually burned—releasing CO2 in the process -the trees that had previously been absorbing excess CO2 are no longer able to absorb CO2 from the atmosphere once they are cut down

Explain the mimicry employed by Viceroy butterflies as an example of coevolution. (lecture, 18.1)

-mimic monarch butterflies -organism mimics a species that is unpalatable (not pleasant to taste) to predators

Explain the role domestication played in the development of early agricultural systems. (lecture, 17.3)

-monoculture (have a field that contains only one plant) -selecting seeds from plants that had desirable characteristics

Compare and contrast food waste between richer and poorer countries. (article)

-poor countries food is often lost between the farmer and the market, due to unreliable storage and transportation. -In rich countries most of that waste occurs in homes, restaurants, or supermarkets.

Describe the process of domestication of plants and animals and explain how it likely got its start. (17.3)

-selecting seeds from plants and selecting characteristics from animals that were desirable -involves artificial selection -Africa and Eurasia began to domesticate animals for a food source.

Describe a synapse and explain the need for a neurotransmitter. (11.1)

-small gap (space) between two different neurons-allow neurons to transmit electrochemical nerve signals from one neuron to the next. A nerve signal passes from one neuron, across the synapse with a neighboring neuron, and is carried downstream by the receiving neuron. Every neural connection has an associated synapse. contains: -presynaptic axon -microtubule -lots of mitochondria -neurofilament -synaptic vesicles -vesicle releasing neurotransmitter -neurotransmitter -dentrites

Describe the typical response of a predator to the introduction of an exotic species to its food web. (lecture, 18.1, 18.3)

-the community is vulnerable to the exotic species -not native to the community and did not coevolve with the rest of the organisms in the community

Describe the concept of Carrying Capacity and how it relates to the human population. (18.1)

-the theoretical maximum size of a population of a particular species that an ecosystem can support indefinitely -includes such things as the available food supply for the species, predation on the species, and any other factors present in the environment that might affect the survival or reproduction of the species.

Describe approximately when agriculture began and what life was like for early humans prior to agriculture. (17.1, 17.3)

-thought to have begun around 12,000 years ago. -before agriculture= Early people had to figure out which parts of the plant would result in new plants (seeds). This was likely accidental at first, then the knowledge was passed on from generation to generation

Describe how each of the following drugs affects dopamine levels in your brain: cocaine, amphetamines, nicotine. (lecture, 11.1)

Cocaine: - blocks the normal absorption of dopamine. As a result, dopamine accumulates in the synapse, where it stimulates the receiver cell. Amphetamines: - stimulate excess release of dopamine, overwhelming the processes of reuptake and enzyme breakdown Nicotine:- stimulates the release of dopamine, while another substance in cigarette smoke blocks the action of MAO

Describe how each of the following can result in paralysis: damage to nerve, tetanus toxin, nerve gas, botulism toxin. (lecture, 11.1, 11.2)

Damage to nerve: Tetanus: Nerve gas: Botulism: -blocks acetylcholine from being released at neuromuscular junction so nerve impulse does not reach muscle -can cause paralysis -found in food

Compare and contrast a synapse and a neuromuscular junction. (11.1, 11.2)

Difference: - Neuromuscular junction (NMJ) is between a neurone and a muscle. A synapse is neurone-neurone. - Neuromuscular junctions are only ever excitatory whereas a synapse can be excitatory or inhibitory. - Neuromuscular junctions use T-tubules to carry the signal quickly, synapses don't. Similarities: - They both use acetylcholine as a neurotransmitter and therefore acetylcholinesterase to prevent constant impulses. - They are both triggered by action potentials on the pre-synaptic membrane. - Depolarisation occurs on the post-synaptic membrane to cause a response

Describe crop diversification and crop rotation. (article)

Diversification: -to produce many different crops -Reduces susceptibility to diseases and pests Rotation: the system of growing a different crop in a field each year to preserve the fertility of the land

Describe dopamine and the enzyme monoamine oxidase (MAO). (11.1)

Dopamine: -a neurotransmitter produced by cells of the brain -serves as a signal that the action promotes survival or reproduction Monoamine oxidase: -quickly reabsorbs or breaks down dopamine

Describe the current vaccinations rates for children in the U.S. (lecture, 12.3)

Going down 77% of children are fully vaccinated, the rest are only missing a few shots

Summarize the development of pesticide resistance in pest species. (lecture, 13.1)

In the beginning, most pests were sensitive to DDT but a few were resistant --> The resistant forms survived and reproduced --> In the end, most pests were resistant to DDT (this is another example of evolution)

Explain why a neurotransmitter must be "cleaned up" after it has bound to its receptor site. (11.1)

MAO cleans up dopamine so that when the next "pleasure" comes along, you will still feel pleasure Need neurotransmitters to either: 1) propagate the nerve signal to the next neuron 2) initiate a muscle contraction, if the neurotransmitter is released into a neuromuscular junction

Describe the general concept of vaccination and how it results in immunity from a particular disease. (12.3)

Most vaccines use a form of the pathogen that has been altered so that it is not capable of causing disease (symptoms) in the vaccine recipient, but the vaccine still results in the formation of antibodies and memory cells protecting you from the disease. Vaccines provide a mechanism for the recipient to produce memory cells and antibodies without having to first go through the initial stages of the immune response to a potentially deadly disease such as smallpox.

Describe Pangaea and Continental Drift, and how they influenced Evolution. (lecture, 18.1)

Pangea: - A supercontinent containing all of Earth's land that existed about 225 million years ago. Continental drift: - the gradual movement of the continents across the earth's surface through geological time.

Describe how an aggressive vaccination campaign resulted in the worldwide eradication of smallpox. (lecture)

The World Health Organization (WHO) began a vaccination campaign against smallpox in the 1960s --> Decline in Number of Countries Reporting Smallpox Cases -->Areas afflicted with smallpox declined during the 60s and 70s --> Smallpox was eradicated in the wild by 1977

Compare and contrast the Sabin and Salk vaccines for polio. (lecture)

Sabin: made of live but weakened polio viruses -introduced in 1961 take orally protects against polio and against carrying polio in rare cases a person can get polio from vaccine Salk: made of killed polio viruses -introduced in 1955 protects against polio but a person can carry it

Describe the three types of neurons: sensory, intermediate, and motor. (11.1)

Sensory:-specialized neuron that undergoes an electrochemical change in response to an event in the outside world, and transmits a signal through the nervous system.-uniquely respond to the type of input that characterizes that sense (vision, hearing, touch, smell, taste).

Describe coevolution and give examples. (18.1, 18.3)

Species in food webs have evolved together so that they are dependent on the presence of each other

Compare and contrast domestication of an animal and taming of an animal. (lecture, 17.3)

Taming: -training animals(wolf pups, being social animals, would likely bond with their new pack (humans) and live peaceably among the human members of its "pack.") domestication: -selecting certain traits that are desirable so that the animal's offspring will have those desirable traits

Describe booster shots and the recommendations for when adults should receive tetanus, pertussis, influenza vaccines. (lecture, 12.3)

booster shots are given, not because your immunity diminishes, but in order to strengthen your immunity A repeat application of a vaccine necessary for long-lasting or full immunity to a particular pathogen. Tetanus:- Once every 10 yearsPertussis:- 1 dose, repeat for every pregnancyInfluenza:- 1 dose annually

Describe the cause, symptoms, and potential long-term consequences of polio. (lecture)

cause: virus that in some people attacks the nervous system and prevents nerve impulses being sent to the muscles symptoms: muscles weaken and a person can become crippled or die long term consequences: paralysis or muscle weakness remains for life

Describe the current population and projected future population through 2050. (18.2)

current: 7.7 billion people future: exceed 9 billion people

Explain the effect of vaccination on a person's antibody concentration and number of memory cells. (lecture, 12.3)

formation of antibodies and memory cells protecting you from the disease. Vaccines provide a mechanism for the recipient to produce memory cells and antibodies without having to first go through the initial stages of the immune response to a potentially deadly disease

Explain what happens in a population when there is a decrease in the percentage of people getting vaccinations for a disease. (lecture, 12.3)

if there is a decrease of people receiving the vaccine for a disease, they can contract that disease and bring it back into the communitythe disease can then grow immune to its own vaccine

Explain why agriculture made it possible for humans to live in large cities. (lecture, 17.3)

only possible after we domesticated wild plants and animals and developed agricultural systems, that could provide large amounts of food to high density human populations

Describe the structure and function of a nerve cell (neuron). (11.1)

structure: -dendrite-soma (cell body)-nucleus-myelin-scwann cell-axon-axon terminal-synapse function:transmit or process information