Bio 1010 - Final Exam - Dulai
Directional Selection
- allele frequencies shift in one direction Caused by: 1. Environment selects against a particular phenotype (colors that stand out in an environment), or 2. A new mutation/allele may be advantageous in an environment
Describe the lysogenic cycle
- in the lysogenic cycle, following penetration into the cell, the viral DNA integrates into the host cell's DNA; UNLIKE the lytic cycle, the virus remains inactive (or latent) - as the host cell divides, the viral DNA is replicated along with the host cell DNA, thus creating new cells that contain the virus. The virus remains latent until some environmental factor signals it to reenter the lytic cycle and begin the process of biosynthesis and maturation
Stabilizing Selection
- intermediate forms are favored and extremes are selected against and eliminated over time 'Goldilocks' selection: ex: body mass in weavers Too large = slow, prone to predation Too small = not enough fat stores, potential starvation
How do viruses infect cells?
- most viruses are very specific in the types of cells they infect; this is specificity is the function of the proteins located on the capsid of the virus - proteins often have complex 3D shapes, and in the case of the capsid proteins, these complex shapes allow the virus to target specific molecules on the surface of the target cell - these molecules may be other proteins, receptors on the surface, or other molecules integrated into the membrane of the host cell
Cell-mediated immunity
- targets cells of our bodies that have become INFECTED with pathogens and are presenting the antigen - makes use of T lymphocytes, which are white blood cells produced in the bone marrow; after being formed, T lymphocytes travel to the THYMUS where they MATURE. As they mature, each T lymphocyte develops RECEPTORS THAT WILL ALLOW IT TO RECOGNIZE A SINGLE FORM OF ANTIGEN
Describe the progression of cancer as it develops.
1. A cell or small group of cells disregards its genetic programming. 2. A cell or small group of cells begins dividing uncontrollably. 3. A tumor is formed. 4. Tissues and organs are impacted from the excess cell growth.
What are the steps in order to describe the process of DNA cloning?
1. A gene for insulin is removed from a human cell 2. Plasmids isolated from bacteria are incubated with the insulin gene and DNA ligase 3. Recombinant DNA is created 4. Bacteria are made to take up plasmids containing recombinant DNA 5. Bacteria produce insulin, which can be extracted, purified, and used
Amniocentesis
1. A needle is inserted through the abdomen 2. Cells are removed from amniotic fluid 3. Cells use used to obtain DNA for karyotypes 4. Cells obtained have DNA that is used for genetic testing
Chorionic Villus Sampling (CVS)
1. A suction tube is inserted vaginally 2. Cells are removed from the chorion 3. Cells obtained have DNA that is used for genetic testing 4. Can use used to obtain DNA karyotypes
What are the traits of Tumor Suppressor Genes?
1. Code for proteins that decrease cell division 2. Promote apoptosis 3. Can become cancer-causing genes when mutated - examples include RB and p53
What are the traits of Proto-oncogenes?
1. Code for proteins that increase cell division 2. Prevent apoptosis 3. Located at the end of a stimulatory pathway induced by injury 4. Can become cancer-causing genes when mutated
It is actually the ___?___ of molecules between chloroplasts and mitochondria that allows a ___?___ of energy from the sun through all living things.
1. Cycling 2. Flow
Describe gene expression in cells, in order.
1. DNA within the nucleus serves as a template. 2. mRNA is processed before leaving the nucleus to a ribosome within the cytoplasm. 3. tRNAs carry amino acids to the mRNA. 4. The amino acids bond together to form a growing protein chain. 5. The protein chain and mRNA molecule break off from the ribosome. 6. The protein chain is further modified and the mRNA strand is used again.
What ways has climate change impacted biomes?
1. Deforestation and subsequent poor land management is leading to the conversion of forest biomes to desert 2. Increases in temperature and decreases in precipitation lead to the formation on desert biomes 3. Overgrazing and poor agricultural techniques is to leading to the conversion of grassland into deserts 4. Coral bleaching is leading to the destruction of coral reef ecosystems worldwide 5. Ocean acidification is leading to the destruction of sensitive coral reef ecosystems worldwide
What ways has climate change influenced the rate of extinction?
1. Extinction is occurring at unprecedented rates, thought to be the result of human activities 2. As forests are bulldozed for livestock, the risk of extinction of the forest community members increases 3. Amphibians and reptiles are at an increased risk of extinction because of their susceptibility to pollution in their ecosystems 4. It is common for organisms to go extinct gradually as environments change 5. As ocean acidification occurs, members of coral reef communities are at risk of extinction
Which ways has climate change impacted our environment?
1. Frequency of drought and heat waves has increased 2. Reptiles, amphibians, and plants are going extinct at increased rates 3. Diseases that were historically tropical are beginning to spread 4. Severity of drought and heat waves has increased 5. Habitat loss has increased
What two components do all viruses have?
1. Genetic material - may be in the form of DNA or RNA; contains a relatively small number of genes in comparison to a cell 2. Capsid - a protein coat that surrounds the virus; some viruses, such as the influenza virus, possess an envelope that surrounds the capsid
Viruses have spikes. Flu virus has surface glycoproteins. What are the forms?
1. H Spikes (hemagglutin) - 17 different forms 2. N Spikes (enzyme called neuraminidase) - 10 different variation Therefore, H2N5 could exist
What lowers an individual's carbon footprint?
1. Heating through passive solar and geothermal energy 2. Carpooling or taking public transportation
What is natural selection?
1. Individuals vary in their traits: variation exists in a population for heritable traits; this does not just include physical characteristics, such as beak shape, but also physiology and behavior 2. Individuals struggle to exist: populations produce more offspring than can survive, which creates competition for available resources 3. Individuals differ in their fitness: those who have favorable traits will survive at a greater rate than those without them; when these individuals reproduce, they pass these traits on to the next generation; the term FITNESS is often used to describe this reproductive success 4. Populations become adapted to the environment: over time, natural selection increases the FREQUENCY of the advantageous trait in the population and decreases the frequency of detrimental traits; over multiple generations, the population becomes adapted to the new environment
What is correct regarding the concept of entropy?
1. It is the measure of disorder in a system 2. Cells must constantly acquire energy to prevent entropy 3. It is explained by the Second law of Thermodynamics
What is true concerning evolution?
1. It is the unifying theme in the study of biology 2. It is the result of heritable changes in the DNA
What are the stages of the cell cycle and its checkpoints?
1. M - mitosis and cytokinesis occur (cytokinesis, telophase, anaphase, metaphase, prophase) 2. G1 - growth occurs as organelles double 3. G0 5. G0 Checkpoint 4. S - DNA replication occurs as chromosomes duplicate 5. G2 - growth occurs as cell prepares to divide 6. G2 Checkpoint - continues back to #1
These ___?___ join together to form long ___?___.
1. Monomers 2. Polymers
This process requires ___?___ and carbohydrates, and produces ___?____ and water.
1. Oxygen 2. Carbon dioxide
What are the five characteristics in determining if something is alive or not?
1. Process energy and materials 2. Maintain as internal environment 3. respond to stimuli from the environment 4. Reproduce 5. Adapt to changing environmental conditions
Cancer can impact many locations in the body. For example, melanoma impacts the ___?___, while lymphomas impact the ___?___.
1. Skin 2. Immune system
What occurs during inflammatory response?
1. The damaged tissue and nearby immune cells release HISTAMINE, which not only causes fluid to leak from nearby capillaries, this SLOWING the movement of pathogens, but also INCREASES blood flow to the area to DELIVER additional white blood cells (such as macrophages) and CLOTTING FACTORS to repair the wound 2. The MACROPHAGES identify and destroy any bacteria or viruses in the wound area 3. NEUTROPHILS remove dead cels, wound debris, and any pathogens in the area by PHAGOCYTOSIS. If additional assistance is needed, NEUTROPHILS may release CYTOKINES to recruit. more immune cells to the area 4. Clotting factors CLOSE OFF the wound; this causes pressure to build and accounts for the RED, TENDER appearance of inflammation
What impacts climate change?
1. The source of energy used in one's home (coal v. solar) 2. The amount of energy used in one's home 3. Mode of transportation (car v. bus or bike) 4. Diet, especially the amount of beef and dairy consumed
Why is the influenza virus a good model for the study of evolution?
1. The virus reproduces rapidly 2. The genetic material of influenza changes quickly 3. The virus is responsible for a human disease
Describe how invasive species may negatively impact ecosystems.
1. The woolly adelgid were accidentally introduced from Japan. They target hemlock trees and infect them, killing them. This disrupts all organisms that rely on hemlock trees and all other organisms within their food chain 2. The vining plant kudzu was introduced to prevent soil erosion. It outgrows most native species and has reduced the biodiversity in ecosystems where it exists 3. A population of beetles are accidentally imported to a remote island in a shipment of timber. The beetle begins to infect the trees on the island, damaging them and impacting organisms that rely on those trees 4. Lionfish were introduced off the coast of Florida and outcompete with native species of grouper and snapper, reducing their populations and impacting the rest of the food chain
Describe the life cycle of a virus.
1. Virus attaches to a cell. 2. Virus penetrates cell membrane and injects nucleic acid. 3. Viral nucleic acid replicates using host cellular machinery. 4. New viral nucleic acids are packaged into viral particles and released from the cell. Host cell may be destroyed in the process.
What is CHEMICAL ENERGY?
1. energy from the bonds in carbohydrates, fats, and proteins
What is SOLAR ENERGY?
1. energy from the sun 2. the source for nearly all life
How is energy created and utilized in a biological organism? (think ATP)
1. energy is released during cellular respiration 2. ATP occurs 3. split into energy for cellular work (e.g., protein, synthesis, muscle contraction) and ATP+P
What is MECHANICAL ENERGY?
1. includes kinetic and potential energy 2. the energy of position or the position of an object before it moves
Describe the structure of a typical animal cell
1. vesicle 2. centrioles (in centrosome) 3. rough ER 4. mitochondrion 5. lysosome 6. smooth ER 7. plasma membrane 8. Golgi apparatus 9. cytoplasm 10. nucleus 11. chromatin 12. cytoskeleton 13. ribosome
It is expected that up to ___?___ of these reefs will be lost by the year 2050.
90%
What is a virus and it purpose?
A virus is the parasites of our cells; it varies in shape and in the types of cells they infect - THEY NEED A HOST CELL IN ORDER TO REPLICATE Its purpose is to find a host cell, hijack the metabolic machinery of that cell to produce more copies of itself
Describe the five stages of the lytic cycle.
APBMR 1. attachment: the structure of the proteins in the capsid allows it to recognize and target specific cells for infection 2. penetration: once the virus has identified the host, its genetic material enters the cell; this can occur by injecting the genetic material directly into the host cell (leaving the capsid outside), or by convincing the host cell to engulf the entire virus (a process called ENDOCYTOSIS). In the case of influenza, the latter process occurs and once in the call the virus releases its genetic material into the host cell 3. biosynthesis: at this point, the virus hijacks the host cell's machinery to manufacture new capsid proteins and copies of its genetic material; energy and materials for these processes are all provided by the host cell 4. maturation: also known as ASSEMBLY, this is when the pieces of the virus are assembled 5. release: finally, the new viruses are ready to leave the cell; this is possible by either causing the host cell to burst (called lysis) or by exiting through the plasma membrane (exocytosis). Viruses that possess an outer envelope leave by endocytosis. As they exit, they often create an envelope about themselves by acquiring pieces of the host cell's plasma membrane
Mitochondria are organelles that complete the breakdown of carbohydrates to produce energy that is used to build ____?____ molecules.
ATP
How are influenza viruses named?
According to their host (in case it's not human), type (A or B), strain, and year of isolation
Describe the role of the chemical signals of the immune response: Interferon
Acts as a SIGNAL to nearby cells that a cell has been infected by a virus
Adaptive immunity
Adaptive immunity: targets specific antigens associated with a pathogen; has the ability to target cells of the body that are infected with the pathogen, while also responding to any pathogens that are free in the blood or interstitial fluid of the body
Coral reefs are composed of coral and ___?___ that interact in a symbiotic relationship.
Algae
The ___?___ are photosynthetic and provide coral with food in exchange for a habitat.
Algae
Which ingredients in an influenza vaccine help the immune system identify the flu virus?
Aluminum salts
What is an ANTIGEN?
An antigen is ANY substance that produces a SPECIFIC IMMUNE RESPONSE by the body; antigens are usually proteins or large carbohydrates that are specific to pathogens such as bacteria and viruses
What is an envelope (not the kind you put letters in)?
An envelope is the remnants of the plasma membrane of the host cell - it does not function that same manner as the plasma membrane of a cell in the regulation of moving materials into and out of the cell RATHER it assists in the attachment and entry of the virus into a host cell
As climate change continues, the prevalence of vector-borne disease has increased. Why is this?
As climates have warmed and winters have become less severe, the range of mosquitos and ticks has increased, bringing with them the diseases they carry.
Targeting free antigens
At the same time that helper T cells and cytotoxic T cells are working to target infected cells, and the B lymphocytes begin the production of antibodies; this is the SECOND form of ADAPTIVE IMMUNITY and is often referred to as antibody-mediated immunity
A method of genome editing that uses the Cas9 enzyme to identify and cut specific nucleotides from the genome is called ___?___.
CRISPR (clustered regularly interspaced short palindromic repeats)
Which types of atoms are found in all organic nutrients?
Carbon and Hydrogen
Who proposed that natural selection allows populations to adapt to a new environment, and is the basis of the process of evolution?
Charles Darwin
Best describe the occurrence and function of checkpoints during the cell cycle
Checkpoints occur during the G1, G2, and mitotic phases of the cell cycle and help regulate the rate at which the cell moves through the different phases of the cell cycle.
This is called ___?___ and in addition to human activities, is leading to the loss of coral reef habitats.
Coral bleaching
Notice that the by-products of one process are used as the reactants for the other process. This is referred to as the ___?___ of molecules.
Cycling
Researchers can use ___?___ to determine patterns of gene expression between cell types, tissues, or individuals.
DNA microarrays
What is a component of a virus?
DNA or RNA and Capsid
The method of determining the exact nucleotide order of a sequence of DNA is called ___?___ and is now an automated process that involves fluorescent dyes and automated machines.
DNA sequencing
The process of ___?___ can provide researchers information on the exact sequence of nucleotides in a gene of interest.
DNA sequencing
What is the function of the LYMPHATIC SYSTEM?
Defends against disease
When enzymes link monomers together, the reaction is called a ___?___ reaction and water is made as a byproduct.
Dehydration synthesis
When does histamine cause capillary beds to be leaky, thus slowing the movement of pathogens into a wound?
During the inflammatory response
Influenza viruses target which types of cells in the body?
Epithelial cells
This is a form of ___?___ gene therapy.
Ex vivo
Disruptive Selection
Forms at both ends of the range of variation are favored; intermediate forms are selected against
Which group is suspected of causing climate change?
Fossil fuel usage, deforestation, and agriculture
Describe the function and whether it is specific or nonspecific of the cell type: NATURAL KILLER (NK) cells
Function: Destroy cells of the body that have been INFECTED by viruses or bacteria nonspecific
Describe the function and whether it is specific or nonspecific of the cell type: MACROPHAGES, dendritic cells, and neutrophils
Function: Destroy pathogens by PHAGOCYTOSIS nonspecific
Describe the function and whether it is specific or nonspecific of the cell type: B LYMPHOCYTES
Function: Produce ANTIBODIES to target specific antigens in the fluids of the body specific
Describe the function and whether it is specific or nonspecific of the cell type: T LYMPHOCYTES
Function: TARGET cells that have been infected by a specific pathogen specific
Genes of interest can also be inserted into bacteria and ___?___ can also be used to create copies of genes or gene products.
Gene cloning
Describe the role of the chemical signals of the immune response: Interleukin
Glycoprotein that is involved in REGULATING the genera immune response
Where are GLYCOPROTEINS located and what do they act as?
Glycoproteins are located along the plasma membrane of the cell and act as IDENTIFICATION TAGS
Give an example of a virus in humans that uses the lysogenic cycle.
HIV - scientists have estimated that almost 8% of the human genome is actually viral in nature, and thus evidence of how active the lysogenic cycle has been in our evolutionary history
Give an example of RNA in humans.
HIV, influenza
Describe the physical barriers for pathogens: Stomach
HYDROCHLORIC ACID (low pH) destroys bacteria and other pathogens
The goal of treatment is to produce new cells that lack the sickle-cell trait and can produce normal ___?___ molecules.
Hemoglobin
As ___?___ water temperatures stress the coral, they expel their symbiotic hosts and die over time.
Higher
Clinical trials have been started for ___?___ and results are promising.
Humans
When enzymes break polymers, the reaction is called a ___?___ reaction and water is broken and used in the reaction.
Hydrolysis
The chills and fever associated with the flu are the result of a reaction by which body system?
Immune system
Describe the role of the chemical signals of the immune response: Histamine
Increases the permeability of the capillaries and causes FLUID to be released into the area of a wound
A virus has been identified as H7N9. Based on this information, which class of virus would it belong to?
Influenza A
When cancer strikes, the body ___?___ the ability to control this process.
Loses
What is present is present on the surface of EVERY body cell (with a nucleus) to identify self?
MHC-I
Viruses are NOT living. Why? What needs to be confirmed?
MR. GRE(y) + Metabolize Reproduce Grow Evolve + = DNA + = Cells - viruses are NOT capable of processing energy or materials, and instead rely on a host cell for those processes
Describe the physical barriers for pathogens: Respiratory tract
MUCOUS membranes trap microbes; they contain CHEMICALS that protect against pathogens; CILIA
Potential energy and kinetic energy are forms of what kind of energy?
Mechanical Energy
Experiments using ___?___ have shown promising results, with large numbers of therapy recipients exhibiting normal hemoglobin production.
Mice
Most organic molecules are composed of smaller subunits called ___?___.
Monomers
What is one of the strongest forces that drive evolution?
Natural Selection (it acts to change allele frequencies)
Within the structure of DNA are the ___?___, A, T, C, and G; deoxyribose sugars, and phosphate groups.
Nitrogen bases
Describe the physical barriers for pathogens: Skin
Normal bacteria (flora) on the surface, along with chemicals released by oil and sweat glands, INHIBIT BACTERIAL GROWTH
Describe the function of the THYMUS.
Organ where T LYMPHOCYTES MATURE
Describe the function of the SPLEEN.
Organ where blood is FILTERED and CLEANED by the action of white blood macrophages
How does the immune system work?
Our immune system has SEVERAL LEVELS of defenses, from NONSPECIFIC PHYSICAL BARRIERS to CELLULAR MECHANISMS of protecting us from specific pathogens, such as the influenza virus
The process of ___?___ uses an automated machine to allow researchers to make multiple copies of genes quickly.
PCR
What produces antibodies?
Plasma cells
What is the function of the MUSCULAR SYSTEM?
Protects and supports internal organs, as well as produces heat
These amino acids are linked together within ribosomes to form ___?___.
Proteins
Which method of producing a vaccine does not require the use of the entire influenza virus?
Recombinant method
What produces immune system cells?
Red bone marrow
What is the function of the NERVOUS SYSTEM?
Regulates and coordinates the activities of other systems
Which enzyme converts viral RNA to DNA in the host cell?
Reverse transcriptase
Chloroplasts are organelles that capture ___?____ and use it to convert water and carbon dioxide to carbohydrates.
Solar energy
Because sickle-cell disease targets red blood cells, ___?___ are a good target for gene therapy.
Stem cells
What is the function of the DIGESTIVE SYSTEM?
Supplies blood with nutrients and water for cells
What is the function of the RESPIRATORY SYSTEM?
Supplies oxygenated blood to tissue cells and rids blood of carbon dioxide
What is inflammation?
Swelling, pain, redness, and heat
How does the immune system remember past pathogens?
The adaptive immune response also has the ability to remember past exposures to pathogens; this characteristic is called MEMORY - some of the activated B cells are held in reserve and not used in the first response to the antigen; instead, they wait for a future exposure
Cytokines
The chemical signals of the immune response are collectively called cytokines; a cytokine is a small PROTEIN that is usually involved in a local response to a pathogen
What are INNATE DEFENSES?
The defenses that act as GENERAL DEFENSES meaning the are NOT targeting a specific pathogen, are collectively called the innate defenses
What is the flu?
The flu is caused by a type of virus, known as the influenza virus
How does the immune system recognize SELF from NON-SELF?
The immune system distinguishes "self" from "non-self" by a SERIES OF MARKERS present on the PLASMA MEMBRANE OF EACH CELL
What is the immune system?
The immune system is responsible for PROTECTING our bodies from foreign PATHOGENS, such as VIRUSES and BACTERIA, and works very closely with the LYMPHATIC SYSTEM
What is the lymphatic system involved with?
The lymphatic system is involved in returning fluids (called lymph) from the tissues of the body back to the circulatory system
How does the flu vaccine work?
The primary response holds the first exposure to the vaccine, and lasts 0 to 59 days. The secondary response begins at 60 days, around 90 days the plasma antibody concentration is at its peaks, and slowly decreases
The chemical reactivity of an organic molecule is largely determined by what?
The types of functional groups that are attached to the hydrocarbon chain
Provide a correct statement concerning the influenza A virus.
The virus uses H and N spikes to target its host cell
Why is the memory of the immune system useful?
This is useful because if you are exposed to the same pathogen again - for example, the SAME influenza virus - the adaptive response can be much FASTER and MORE efficient - MEMORY T CELLS are also produced by the cell-mediated immunity pathway
Describe the function of LYMPH NODES.
Tissue where interstitial is FILTERED and CLEANSED by white blood cells called MACROPHAGES
Describe the function of RED BONE MARROW.
Tissue where the LYMPHOCYTE CELLS of the body are PRODUCED. Location where B LYMPHOCYTES MATURE
What is the function of the CARDIOVASCULAR SYSTEM?
Transports oxygen rich blood and wastes to and from cells
What happens when pathogens are ingested by the MACROPHAGES and DENDRITIC CELLS?
When pathogens are ingested by the macrophages and dendritic cells of the immune system, they are digested, and a small portion of the pathogens is ATTACHED to the SURFACE of the macrophage
Targeting infected cells
When the influenza virus enters into an epithelial cell on the surface of our respiratory tract, the INFECTED CELL responds by posting an antigen on its surface, attached to a MHC-I marker. - this acts as a FLAG for the cytotoxic T cells, which were just activated by the helper T cells
Who typically names influenza viruses?
World Health Organization (WHO)
How may evolution be defined as?
a CHANGE in the frequency (math) of ALLELES of a gene in a population from one generation to another A = 10%; a = 90%, then A = 10.5%; a = 89.5% = we have EVOLUTION
Human society in its current form is unsustainable because....
important natural resources are being consumed more quickly than they can be replenished.
Give an example of DNA in humans.
small pox, chickenpox, and herpes