Bio EOC

The illustration below shows four lobes of the human brain. What lobe is designated by label 2?

parietal

Which lobe of the brain is designated by number 4?

temporal

A diagram representing the relationship between photosynthesis and cellular respiration is shown below. The numbered boxes in the diagram represent which of the following?

1 - oxygen; 2 - carbon dioxide. Photosynthesis by plants produces oxygen, which is then used by animals as a reactant in cellular respiration. The product of cellular respiration is carbon dioxide, which is used by plants in photosynthesis. And the cycle continues.

While genetic engineering has positive benefits, there are also concerns associated with widespread use of genetic engineering in agriculture. If many farmers begin to plant more genetically modified crops that have an increased tolerance to insects, which of the following may result?

A decrease in genetic diversity of the crops. Genetic modifications of organisms does not allow for random mutation in the genetic code. This random mutation is responsible for the genetic diversity seen in populations of organisms.

What is the human embryo called after the eighth week of development?

A fetus. Human gestation is divided into two phases: the embryonic phase, which lasts through the 8th week, and the fetal stage, which lasts from 9 weeks until birth. Most major organs and structures are formed during the embryonic stage. The fetal stage is characterized by rapid growth.

The rate at which blood flows through the human body changes in response to many factors. Which statement describes one of these factors and its effect on blood flow?

A high viscosity of blood causes an increased resistance in the blood vessels and leads to slow blood flow. Viscosity refers to the thickness of blood. This thickness is caused by the number of red blood cells. Thick blood travels through blood vessels at a slower rate than thin blood.

Which of the following describes a way that a person's health can be affected by heredity?

A person with a family history of high blood pressure is more likely to have heart disease. Family history can affect a person's health in some areas by making them more likely to contract certain diseases. The genes that code for some diseases are hereditary, and can be passed from generation to generation.

Which of the following describes fertilization?

A sperm joining an egg to form a zygote. Fertilization of the egg by a sperm happens in the uterine tube and the zygote begins to undergo mitosis to form a blastocyst.

If the xylem in a young tree is damaged, which process is first affected?

Absorbing water from the soil. Xylem carries water and nutrients from the soil, up into the leaves. The water is used to carry out photosynthesis, the products of which are sugar and oxygen.

Salt water is an abundant resource but unusable for irrigation and drinking. As demands on freshwater sources increase, the use of desalination processes to remove salt from ocean water is increasing. A concern of desalinating water is the large amounts of recovered salts that are returned to the ocean. Which of the following describes the most likely impact of desalination on the surrounding ocean environment?

Alteration in ocean salt levels would cause loss of species and unbalanced populations in marine food webs. Any change in abiotic factors (such as salinity) will have effects on the organisms in an ecosystem.

What is the term for a strong response to a harmless antigen in the environment?

An allergy. Reactions to allergens release histamines which cause non-specific responses such as inflammation.

Many species of bacteria have become resistant to antibiotics because antibiotics have been so widely used. Now, bacteria that used to be killed by antibiotics are more difficult to treat. What is the best way to proceed in dealing with this public health problem?

Antibiotics should only be prescribed to people with bacterial infections. Antibiotics are only useful against bacterial infections. When antibiotics are prescribed to individuals that do not have a bacterial infection, any bacteria they may have in their body can become resistant to the antibiotic and the resistant bacteria can multiply.

Which of the following best describes the connection between cardiovascular disease and age?

As people age, plaque builds up in the arteries increasing vessel resistance, which leads to disease. This condition is called atherosclerosis, where the walls of the arteries become thick and inflexible. Atherosclerosis increases resistance in the blood vessels leading to high blood pressure.

A weightlifter is using heavy weights in short bursts for a competition. Because his muscle cells are not able to take in enough oxygen to make very much ATP the weightlifter begins to get fatigue in his muscles. Which of the following processes is most likely going on in the muscles of the weightlifter as he competes in his event?

As the cells run out of oxygen they switch to anaerobic respiration, which allows the cell to make small amounts of ATP in the absence of oxygen. Anaerobic respiration is used by cells in the absence of ATP. This process converts sugars to alcohol and only creates a small amount of ATP compared to aerobic respiration.

Complete burning of plant material returns carbon primarily to the...

Atmosphere. When plant material is burned, carbon is released as carbon dioxide, which enters the Earth's atmosphere.

Which of the following is a limiting factor in a population of organisms?

Availability of food. The availability of food is a limiting factor in a population of organisms. If there is not enough food, some of the organisms will die and the population will decrease in number.

Which of the following is true of a zygote?

It is made up of only one cell. The zygote is a fertilized egg. It is the first cell of a human embryo and contains the same amount of genetic information as all other somatic cells.

How do human diseases caused by bacteria and diseases caused by viruses react to antibiotics?

Bacterial diseases respond to antibiotics; viral diseases do not. There is no known treatment for viral infections. The best defense against a pathogenic virus is a vaccination, which prevents infection if given before exposure to the virus.

Which of the following factors would most directly affect blood flow through the circulatory system?

Blood pressure. The factors that most directly affect blood flow are blood pressure, blood volume, resistance and activity level.

The diagram below shows the relationship between photosynthesis and cellular respiration and the organelles in which they occur. Which statement describes how photosynthesis and cellular respiration are interrelated?

Carbon dioxide and water released by cellular respiration are used in photosynthesis. The products of cellular respiration (CO2 and H2O) are the reactants of photosynthesis. The overall equations for photosynthesis and cellular respiration are the reverse of each other.

Which gas is removed from the atmosphere during photosynthesis?

Carbon dioxide. The reactants of photosynthesis are carbon dioxide and water.

Stem cell research has been a controversial subject in past years. What is the reason for this?

Cells for study are often taken from human embryos. Embryos contain cells that are non-differentiated and can turn into any type of cell in the body. These cells could be used to create new tissues for people with diseases or malformations.

What causes blood pressure?

Contraction of the ventricles in the heart. Blood pressure is caused by contraction of the ventricles of the heart and also by the elasticity of the arterial walls. When the heart contracts, blood pressure is the highest. This is called systolic pressure. When the heart is relaxed, blood pressure is lowest. This is called diastolic pressure. Some pressure is maintained in the vessels at all times, even with the heart is in diastole. This pressure is kept relatively constant by the elastic properties of the walls of the arteries.

The way that crimes are solved today was affected by which of the following technologies?

DNA fingerprinting. Even a tiny section of a person's DNA, left behind at a crime scene can be multiplied many times to make identification possible.

The p53 gene codes for the p53 protein that locates DNA errors for cellular repair. The diagram below shows the relationship among possible environmental influences, the p53 gene, and cancer. Which of the following statements best describes the relationships among possible environmental influences, the p53 gene, and cancer?

Environmental influences can lead to mutations in the p53 gene, which can cause certain cancers. Environmental factors such as pollution, radiation from the sun and public health concerns can lead to changes or mutations in a person's DNA, which can lead to cancers.

Below is a diagram of the male reproductive system. Which structure is represented by the letter D?

Epididymides. The epididymides lie adjacent to the testes and serve as a storage site for sperm on the way to the vas deferens.

In a process called transpiration, plants get rid of excess water through pores in the leaves called stomata. This excess water is then released into the atmosphere as part of the water cycle. Which of the following terms best describes how the released water enters the atmosphere?

Evaporation. Water that is released by plants through transpiration evaporates into the atmosphere to rejoin the water cycle.

Which statement describes the role of flowers in plant survival?

Flowers contain cells that produce gametes. Flowers are the reproductive organs of plants.

Terrestrial plants have stomata on the surface of their leaves. Stomata are surrounded by two guard cells that change shape in response to environmental factors and open or close the stoma. Which of the following best explains how the structure of the leaf is used in processes that occur in plants?

Gases for photosynthesis are exchanged through the surface of the leaf. Gas exchange in leaves is called transpiration and occurs through the stomata.

When an environment has reached its carrying capacity for a certain population, which of the following is true?

Growth and immigration rate is equal to death and emigration rate. Carrying capacity is the maximum population size of a species that can exist in a given environment given the resources.

Which structure in the leaf controls the opening and closing of the stoma?

Guard cells. Guard cells surround stomata and control their opening and closing. The stomata are the site of gas exchange in leaves, a process called transpiration.

A diagram of a food web is shown below. Which organism receives the least amount of energy from the producers?

Hawk. Available energy decreases as you go up a food chain or web. Secondary and tertiary consumers receive less energy than primary consumers.

What kind of genetically modified crops would be most successful in wet-tropical countries that are overcrowded?

High-yield crops that are pest-resistant. If space is limited, high-yield crops would be best. Wet-tropical climates are often plagued by pests so crops that are pest-resistant would do well in those climates.

Why does ice stay at the top of oceans instead of sinking to the bottom?

Ice is less dense than liquid water. As water freezes, its molecules spread apart into a specific arrangement that makes frozen water less dense than liquid water.

The diagram below shows a cross section of a plant leaf. How does the structure marked X contribute to the survival of the plant?

It allows the intake of gases necessary for photosynthesis. The stomata are the site of gas exchange in leaves, a process called transpiration. Carbon dioxide is taken in by plants and oxygen is given off.

What function does ATP carry out in living things?

It is used to capture and transfer energy. ATP is the "energy currency" of cells. Energy is stored in the bonds of this molecule and is released to do work in the cell when the bonds are broken. ATP is created during cellular respiration.

A plant species lives in an area with limited sunlight. Which physiological adaptation would be most useful to the plant?

Large leaves. Leaves are the part of a plant that contains chloroplasts. Chloroplasts are structures that contain chlorophyll, a pigment that captures sunlight and allows the plant to make sugars. The larger the leaf surface a plant has, the more sunlight it can capture.

What is the main function of leaves?

Leaves provide a place for photosynthesis to occur. Leaves contain chloroplasts, the site of photosynthesis in plants.

The drinking of alcoholic beverages by a pregnant woman is harmful to the development of her fetus. This is most damaging early in a pregnancy because during this time...?

Many of the essential organs of the fetus are forming. Most of the essential organs and structures of a fetus are formed in the first 9 weeks of gestation.

Why are there so few aquatic plants and phytoplankton that live at the bottom zones in the ocean?

Most sunlight is absorbed before reaching these levels. Plants and phytoplankton are primary producers that rely on the sun to carry out photosynthesis. The bottom zones of the ocean have little to no light.

Two different species of bacteria are examined. Scientists find that species X always produces CO2 and H2O during cellular respiration. Species Y always produces ethyl alcohol and CO2. Which conclusion can be made from these observations?

Only species Y is anaerobic. Anaerobic cellular respiration converts sugars to ethyl alcohol and carbon dioxide in the absence of oxygen.

When fertilizers run off farmland into streams and ponds, the nitrogen content of the water increases. This can lead to rapid growth of algae in a process called eutrophication. How can this process affect other organisms in the water?

Oxygen is used up as algae is decomposed, reducing the amount available to other organisms. Algal blooms, often caused by high levels of nitrogen in water lead to low dissolved oxygen levels and the death of many species in these ecosystems.

The framework of organic molecules essential to all organisms is composed mainly of carbon atoms. Which processes are involved in the cycling of carbon within an environment?

Photosynthesis and respiration. Photosynthesis captures carbon dioxide from the atmosphere and converts it to glucose. Cellular respiration converts glucose to carbon dioxide.

In which way are photosynthesis and cellular respiration different?

Photosynthesis used carbon dioxide, while cellular respiration produces carbon dioxide. The reactants of photosynthesis are the products of cellular respiration.

Water is often called the "universal solvent" because many substances can be dissolved in water. What property of water allows it to be such a versatile solvent?

Polarity and cohesion. Water molecules are polar. This means that they have slight positive and negatively charged ends. Water molecules are attracted to a wide variety of molecules because of those charges and thus, acts as a solvent for a variety of compounds.

Data on the immigration and emigration of a fish species would be most helpful in determining which of the following?

Population of the species. Population size is determined by births, deaths, immigration and emigration.

Which of the following statements is true about natural systems?

Producers are at the bottom level of both the energy pyramid and the biomass pyramid. Both the biomass pyramid and the energy pyramid have producers at the bottom. Producers account for most of the biomass and most of the available energy in any given ecosystem.

The diagram below shows the cycling of nutrients in an ecosystem. The removal of which of the following groups would cause an immediate decrease in the amount of energy flowing through the system?

Producers. Producers gather energy from the sun and convert it to useable molecules for consumers. Removing producers from any food chain or web will cause an immediate decrease in available energy.

An activity that occurs in the human body is shown below. This activity helps to do which of the following?

Provide protection against pathogens. The antibodies pictured here are recognizing antigens on a foreign cell to mark it for destruction. In this way, the body is able to protect itself against dangerous invaders.

Plant cells that are specialized for cell division are most likely found in what part of the plant?

Root tips. As plant roots grow, the cells in their tips undergo constant mitosis to produce new tissue.

Which of these organisms would most likely be found at the top of an energy pyramid?

Sharks - a secondary consumer. Energy pyramids show the amount of available energy with the lowest levels having the most energy. Producers are found at the bottom of the pyramid, while secondary consumers would be found at the top.

After an initial infection, B-cells recognize the measles virus. How is this helpful in human immune response?

The B-cells produce antibodies more quickly if the measles virus is encountered again. After an initial infection with a virus, B cells are able to recognize the virus and produce antibodies against it the second time. The person's reaction to the virus will be lessened.

Mullet are local estuarine fish that move in schools and feed on plankton and plant matter. Natural predators of the mullet include spotted sea trout, sharks, pelicans and dolphins. The graph below shows how the number of mullet in an area has changed over time. Based on the data, one student concludes that a new predator was introduced into the area during this time period. Which of the following is a likely alternate explanation for the change in the mullet population?

The amount of aquatic plants in the area decreased. If the amount of the major producer in an area is reduced, populations of consumers will also be reduced. Since the mullet feed on aquatic plants, their population would decline in response to declining numbers of plants.

The diagram below shows the flow of carbon in a terrestrial ecosystem. Which will most likely happen if the decomposers are removed from the carbon cycle?

The amount of carbon dioxide in the atmosphere will decrease. Decomposers release carbon into the atmosphere, so if they were removed less carbon would reach the atmosphere.

What is immunity?

The body's ability to produce cells that inactivate foreign cells or substances. The immune system produces specific and non-specific responses to pathogens, and foreign cells and substances. This process helps maintain homeostasis in individuals.

The pH of the water in several lakes in Norway and Sweden had decreased to below 5.0 due to an increase in acid rain. Which of the following is most likely to happen in these lakes?

The decline of several fish populations. Fish are sensitive to changes in pH and would experience a decrease in numbers if a shift in the pH of the water occurred.

Abnormalities present in the cells that line the uterus may prevent the production of offspring by directly interfering with which process?

The development of the embryo. The uterus is the site of implantation and development of the human embryo.

The northern elephant seal was almost hunted to extinction in the 1800s. By the late 1890s, approximately one hundred seals were left, reducing the gene pool of the population. What will be the consequence of this reduction?

The elephant seals will be more vulnerable to environmental change. The more genetic variation a population has, the more easily the population can deal with environmental change. If the gene pool decreases, genetic variation decreases.

How are cellular respiration and photosynthesis related, in terms of energy?

The energy captured in photosynthesis is used to power cellular respiration. Energy from the sun is used captured during photosynthesis and stored in the bonds of glucose molecules. During cellular respiration, this energy transferred to ATP molecules to be used to do work in the cell.

In what way did gene therapy, the replacement of a faulty gene with a normal one, stimulate medical research?

The genes on each chromosome had to be mapped and described. The human genome project mapped out each gene of humans making gene therapy possible.

Which line in the graph above best illustrates an effect of the carbon dioxide level in the blood on breathing rate before, during and after a period of exercise?

The level of carbon dioxide increases during exercise because the cells are undergoing cellular respiration at a faster rate to make more ATP. Carbon dioxide is produced as a product of cellular respiration.

The diagram below represents a flower, the reproductive structure of some plants. Most flowers have both male and female structures for fertilization and reproduction. Which structure is represented by the letter A in the diagram above?

The pistol, a female structure which collects pollen and passes it to the ovary. The pistol is made of several carpels fused together. The tip of the pistol is usually sticky and holds pollen grains when they land there. The style is a tube that leads from the stigma to the ovary, where fertilization occurs to form the zygote.

The cambium is a section of cells in a plant that can become either part of the xylem or phloem, depending on the growth and needs of the plant. If the cambium of a particular plant was damaged, what would be the most likely effect on the plant?

The plant would not be able to transport nutrients and water. The xylem and phloem are responsible for the transportation of nutrients, and water throughout the plant. If cambium cells were damaged, the plant would not be able to make xylem and phloem.

The common brushtail possum is a marsupial native to Australia. This possum was introduced to New Zealand where it had no natural predators and had an abundant food supply. Which of these likely occurred a few years after the introduction of this possum to New Zealand?

The possum population grew to a larger size. With no natural predators, the possum population was allowed to grow unchecked.

The number of pythons found throughout Everglades National Park has increased in recent years. These huge snakes are not native to Florida and are believed to have been released into the wild by pet owners. Wildlife biologists have initiated attempts to capture and remove these pythons. Which statement best explains the biologists' reasons for removing these pythons from the Everglades?

The pythons could prey on native organisms and cause native population to decline. Introduced species often prey on native organisms declining their populations, sometimes to extinction.

How does the predator-prey relationship affect a population?

The relationship controls the population size of both species. The predators keep the prey population under control and the size of the population of prey limits the amount of predators an ecosystem can support.

What is the body's first line of defense against infection by foreign organisms?

The skin. The skin is the first line of defense against foreign organisms. It acts as a nonspecific barrier to water and air-borne infectious agents.

Whaling was a very profitable profession until whale populations crashed. The global community came together to enact a ban on whaling. However, Japan and Norway have not agreed to stop whaling. Which of the following is the most likely consequence of their decision?

The whale populations are not rebounding as quickly as they might if all of the countries agreed not to hunt whales. All countries must work together to prevent major human impact on fragile ecosystems and populations of organisms.

A team of ecologists observed feeding patterns of several populations in the desert. The energy pyramid shown below depicts the feeding patterns the ecologist observed. Which of the following best explains the difference in the amount of available energy in the trophic levels of the desert ecosystem?

There is less available energy in the fourth trophic level because of the loss of energy through metabolism in each of the lower trophic levels. Each successive trophic level contains about 10% of the available energy from the previous trophic level. The other 90% is lost as heat to the atmosphere through metabolism by the organisms in that level.

White blood cells are an important part of the human immune response. Two types of white blood cells, neutrophils and macrophages, act as phagocytes. Phagocytes perform which of the following functions in the human body?

They engulf and destroy bacteria. Phagocytes are whole cells that capture invading cells or pieces of cells by surrounding and engulfing them. Once the invading cell is inside the phagocyte it is killed by enzymes.

What is the main purpose of seeds in plants that have them?

To protect and distribute the zygote. A seed contains a complete zygote wrapped in a seed coat. The seed's hard outer covering protects the seed until it can be dispersed, by wind or animals, to another location. This adaptation allows for a wider distribution of seed plants than those that do not have seeds.

Which technology below would probably be the most important to a person who had diabetes and had to take insulin every day?

Using recombinant DNA to produce human hormones from bacteria. Insulin is a hormone used to regulate blood sugar levels. It is essential to the correct functioning of the body. If bacteria can create insulin, this hormone will be easier for diabetics to get.

A fertilized egg undergoes several stages before it is successfully implanted. The diagram below shows these stages as the fertilized egg travels through the female reproductive system. In which of the following structures of the female human reproductive system is the blastocyst implanted during normal human development?

Uterus. The blastocyst makes its way down the uterine tube and implants in the uterus.

Sperm are created through meiosis in an area of the testes called the seminiferous tubules. Through which structure do the sperm travel to exit the testes?

Vas deferens. The vas deferens leads out of the testes. Here sperm are mixed with fluids to nourish and protect them. This mixture is called semen and travels out of the urethra into the vagina for fertilization of the egg.

Water is essential for life. Its special properties make water the single most important molecule in plant life. Which of the following properties of water enables it to move from the roots to the leaves of plants?

Water exhibits cohesive behavior. Cohesion means that water molecules are attracted to each other and attracted to other substances, such as the walls of the xylem of plants. The water molecules behave this way because they are polar.

Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon?

Water has a high heat capacity. Water can absorb a large amount of energy without a large rise in temperature. This is called heat capacity. As the sun shines on bodies of water, they absorb great amounts of its energy without a large fluctuation in temperature.

Although vaccines cannot be used to treat a person who is sick, they can help to prevent infections. Vaccinations tell the body to create "memory cells", which will function later to create antibodies against certain pathogens. When a person is vaccinated, what are they injected with?

Weakened viruses or antigens from the virus. Vaccinations contain antigens or weakened viruses from specific infections. The viruses are too weak to cause illness in the patient, but strong enough to allow the body's immune system to create B cells against the virus. These "memory cells" are stored in the body until the person is exposed to the virus at which point, they will create antibodies against the virus.

Which of the following are abiotic factors that shape ecosystems?

Wind, precipitation, and soil type. Abiotic factors are those that are non-living.

A community is concerned about the water quality of a nearby lake. Increased sedimentation in the lake is endangering the native habitat. The increased sedimentation is most likely caused by which of the following?

construction of homes along the lake When homes are constructed, trees and plants are removed. Under natural conditions, trees and plants help to secure the soil and prevent erosion and sedimentation in lakes and rivers.

The presence of wastes, such as plastic bags and motor oil, in lakes and streams miles away from developed areas suggests that

ecosystems are interconnected and human action can alter ecosystem equilibrium. Human impacts on the environment can be far-reaching. What we do in our own area of the Earth, can effect what happens in other areas as well.

New fuels are being produced by converting corn and grasses into compounds containing alcohols that can be broken down for energy in various engines. The purpose of this research is to

reduce the use of nonrenewable resources. The use of nonrenewable resources has negative effects for many ecosystems as well as human beings. New ways to use renewable resources for energy are now being developed.

DDT and other pesticides used over 50 years ago are still affecting the environment today. Scientists have found these substances in recent glacier runoff. Glacier runoff occurs during the summer, when precipitation that has fallen on glaciers during the winter is released. Ice layers from existing glaciers have been analyzed. The results of this analysis show that the concentrations of DDT and other pesticides were highest about 10 years after the use of these substances was banned. This information shows that

the decision of one human generation may have an impact on future generations.

A strip mining company wants to lease some land that is currently part of a national park. They promise to reclaim the land should any minerals be mined from the area, and they are willing to pay top dollar for the rights. As an ecologist, what factors would you raise with the local government?

the threat to local biodiversity Any time land is modified from its original natural state, the local organisms will be affected.