bio exam 2

Chloroplasts

(in green plant cells) a plastid that contains chlorophyll and in which photosynthesis takes place.

cancer drops in men and women

1.8%= men 1.4%=women

men chance of getting cancer

1;2

women's chances of getting cancer

1;3

Explain how the activities of a cell are ultimately under the control of the DNA in the cell.

A cell is the smallest unit of biological organization that has all of the characteristics of life. These characteristics include: the ability to acquire materials and energy the ability to respond to its environment the ability to reproduce the ability to maintain an internal environment the ability to adapt to its environment

nuclear membrane

A highly-porous membrane that separates the nucleus from the cytoplasm

tumor

A mass of abnormal cells that develops when cancerous cells divide and grow uncontrollably.

Diagnostic mammogram

A more detailed look at a specific area of the breast, usually because of a suspicious lump in the breast or a blood test that detected blood markers associated with breast cancer.

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction. control center

Endoplasmic reticulum

A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids.

Systemic Radiation Treatment

A variation of internal radiation therapy that is used for some forms of cancer. A radioactive substance is either ingested or injected into the blood.

Dominant

An allele or trait that masks the expression of another allele. Indicated by a capital letter (G)

recessive

An allele or trait whose expression is masked by a dominant allele. Indicated by a lower case letter (g)

Explain how cancer affects normal physiology and results in death - homeostasis.

As a tumor forms, it begins to take up space in the organ. This may, in turn, block ducts, blood vessels, or lymphatic vessels that are needed for the organ to function. For example, breast cancer that has metastasized to the lungs may block airways, reducing the amount of oxygen available to the body. Cancer in the brain may place pressure on areas that are necessary to regulate important body functions, such as breathing. Cancer in the bone marrow may prevent white blood cells from forming, thus leaving the body open to infection.

Understand how mutations in genes that control the cell cycle may lead to cancer - and Proto-oncogenes

Changes to the nucleotide sequence of a DNA molecule are called mutations. A mutagen is an agent that is known to cause mutations in the DNA. If a mutagen is known to be directly associated with a specific form of cancer, it is called a carcinogen

1. Summarize how researchers are investigating new methods of fighting cancer - CRISPR

Cluster Regulated Interspaced Short Palindromic Repeats. it uses enzymes called CAS9, that identifies the specific sequence of DNA to be edited via an RNA molecule that complementary base pairs to the DNA sequence. can remove nucleotides thus inactivating the gene, or insert new nucleotides, thus changing the functions of the genes

• Summarize how chromosomes are involved in transmitting information to the next generation.

Humans, and many other organisms, are diploid organisms. This means we have two copies of each ______________: one we inherited from our biological mother, and one from our biological father. composed of DNA and packaging proteins called histones

• Describe how the information contained within a gene is expressed as a protein.

In individuals with sickle-cell disease, a mutation in a gene associated with the hemoglobin protein causes it to lose its function, and as a result, individuals may suffer from sickle-cell anemia

DNA Ligase

Involved in DNA Replication. Links together Okazaki fragments on the lagging strand.

Helicase

Involved in DNA Replication. Unwraps the DNA double-helix by breaking the hydrogen bonds between complementary paired nucleotides

ribosomes

Makes proteins. a minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.

chemical cause of mutaion

Many chemicals cause mutations directly by modifying the nucleotide sequence or by interfering with the replication of the genetic material

viruses caused by mutations

Many chemicals cause mutations directly by modifying the nucleotide sequence or by interfering with the replication of the genetic material

Four daughter cells are created

Meiosis

Two cell divisions

Meiosis

Associated with growth and asexual reproduction

Mitosis

Ending daughter cells are diploid (2n)

Mitosis

Beginning parent cell is diploid (2n)

Mitosis and Meiosis

Involves the duplication of chromosomes before cell division begins

Mitosis and Meiosis

Pairing of homologous chromosomes

Mitosis and Meiosis

• Compare and Contrast the processes of mitosis and meiosis.

Mitosis occurs through a total of four steps, whereas, meiosis occurs through a total of eight steps. Mitosis produces two diploid daughter cells as a result, whereas meiosis produces four haploid daughter cells as a result. Mitosis occurs in somatic cells (body organs), whereas meiosis occurs in germ cells (gametes).

Amniocentesis

Obtains a sample of amniotic fluid from the uterus of a pregnant woman by passing a long needle through the abdominal and uterine walls to collect fetal cells

Chorionic villus sampling

Obtains a sample of fetal cells in the region where the placenta will develop. An ultrasound is used to place a thin suction tube through the vagina into the uterus

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

radiation cauising mutations

Radiation can cause structural changes to the DNA molecule during DNA replication that result in mutations.

screening mammogram

Recommended for women over 40, to look for any abnormalities in the breast that may potentially be associated with cancer.

Vesicle

Small membrane-bound sac that functions in moving products into, out of, and within a cell.

Computerized tomography (CT) scans

Sometimes also called CAT scans, these are a special type of X-ray procedure that takes pictures of the organs from different angles. A computer then assembles these images to generate a multi-dimensional view of the internal organs. This test involves an injection of a contrast dye into the circulatory system. CT scans are useful for detecting whether the cancer is spreading to other organs or if a treatment is being effective.

DNA polymerase

Synthesizes new daughter DNA strands using the information in the template strand. (Involved in DNA Replication)

blood marker tests

The analysis of the blood test will involve a look for specific proteins in the blood that are associated with cancer. They look for proteins that are being produced by cancer cells or tumors.

Genotype

The combination of alleles in an individual. EX; GG, Gg or gg

• Explain how scientists determined that DNA is the genetic material.

The first of these experiments was performed by the scientist Frederick Griffith in the 1920s.Griffith worked with two forms of bacteria in his experiments. The first, called the S strain, was a virulent strain which had a capsule that surrounded the bacteria. This strain killed mice when injected into them. The second was known as the R strain. This strain lacked a capsule and was not lethal. However, although mice injected with heat-killed S strain bacteria (Fig. 2.2c) did not die, if the heat-killed S strain were injected into a mouse along with live R strain bacteria, the mouse died (Fig. 2.2d). Interestingly, the bacteria that were extracted from the dead mice were live S strain! From these results, Griffith recognized that something in the dead S strain was providing information to transform the R strain into live S strain bacteria.

codons

The information in the mRNA molecule is read as a series of triplets,

external radiation treatment

The most commonly used form of radiation therapy. During this procedure, a patient is placed in a specific position so as to maximize the effectiveness of the energy beam. Often, the process is accompanied by a CT scan so the radiology technician knows exactly where to target the beam of energy. Most external radiation therapies use X-rays, although, depending on the location of the tumor, some require the use of higher-energy gamma rays.

CRISPR

The most widely used geno editing is called clustered regularly interspaced short palindromic repeats. Uses an enzyme, called Cas9, that identifies the specific sequence of DNA to be edited via an RNA molecule that complementary base pairs to the DNA sequence. CRISPR may be used to either remove nucleotides, thus inactivating the gene, or insert new nucleotides, thus changing the function of the gene. has been used to inactivate cell-cycle control genes that had lost their ability to function.

Phenotype

The physical characteristics of the trait. EX; Green or yellow pods

the importance of check points

The series of checkpoints in the cell cycle regulate the speed at which the cell moves through the cycle and ensure that the cell is actually ready for cell division. These checkpoints are under the control of proteins that check the DNA of the cell for specific requirements.

Positron Emission Tomography (PET scan)

This scan examines how the cells of the body are functioning by providing them with sugar that contains a small amount of a radioactive tracer. Cells that are more active, such as cancer cells, will take up more of the sugar, and will stand out from the cells around them. In breast cancer, this test is useful in determining whether the cancer has moved to nearby lymph nodes or tissues.

Magnetic Resonance Imaging (MRi)

Unlike other tests, an MRI does not use radiation. Instead, it uses radio waves and magnets to generate detailed pictures of the body. For breast cancer, MRIs are used for both screening of high-risk patients and to diagnose the extent and spread of the cancer in the body.

1. Understand how cells divide normally and how cell division is regulated. - Cell Cycle,

We can divide the cell cycle into two major parts: Interphase. Interphase is where the cell spends the majority of its time. For example, if we consider the life cycle of a cell to be 24 hours, then around 22-23 hours would be spent in interphase. During interphase, the cell performs all of its normal functions. M Phase. This is the phase of the cell cycle when cell division occurs. M phase consists of two parts: (1) mitosis, during which the genetic material is equally divided into two new nuclei, and (2) cytokinesis, during which the cytoplasm and organelles are divided to form two new identical daughter cells. We will take a closer look at both of these processes later in this lesson.

DNA Microarrays

Which is basically a glass (or silicon) slide with each gene located at a precise location. it may be used to identify a specific allele or to look at patterns of gene expression between two cell types, tissues, or individuals

race the path of 1)transcription to 2)translation in the formation of a protein from DNA.

_________ involves the following stages: The RNA polymerase binds to an area at the start of a gene called a promoter (not shown in The promoter acts as a regulatory region for turning genes on and off. The RNA polymerase unwraps a small section of the DNA, exposing the template strand of the DNA. The RNA polymerase uses the template strand to make a complementary RNA copy, called messenger RNA (mRNA). RNA molecules use uracil (U) in place of thymine (T) _______________ occurs as a series of steps: The ribosome assembles around the mRNA molecule so that the AUG codon on the mRNA is the first codon to be processed. A tRNA with an anticodon that complements the mRNA codon enters the ribosome with the first amino acid. A second tRNA, with an anticodon complementary to the second mRNA codon, enters the ribosome. A peptide bond is formed between the two amino acids, and then the first tRNA leaves the ribosome. The ribosome moves down one codon on the mRNA, and a new tRNA enters with the amino acid coded for by the newly exposed codon on the mRNA. The process continues until a stop codon is reached on the mRNA, at which time the entire complex disassembles.

carcinoma

a cancer arising in the tissue of the skin or of the lining of the internal organs.

Golgi Apparatus

a cell organelle that helps process and package proteins and lipid molecules, especially proteins destined to be exported from the cell. Named after its discoverer, Camillo Golgi, the Golgi body appears as a series of stacked membranes.

• Explain the structure of hemoglobin and its function in the circulatory system.

a complex protein that consists of four polypeptide chains, called globins. each polypeptide of the hemoglobin protein contains a heme group. This heme group contains iron, which readily interacts with oxygen. Changes in the structure of the globin chains, as occurs in sickle-cell disease, limits the ability of hemoglobin to interact with a heme group. When hemoglobin picks up oxygen, it forms oxyhemoglobin. When the oxyhemoglobin reaches metabolically active tissues, such as a muscle, the oxygen diffuses from the hemoglobin, out of the red blood cell, and then into the cell that requires the oxygen.

• Identify the basic characteristics of a genetic disease.

a disease that is caused by a change (mutation) in the genetic information of an individual that can be passed on from one generation to the next. such as sickle-cell disease and cystic fibrosis, may be passed on from one generation to the next.

1. Describe how cancer is a physiological disease that occurs at the cellular level.

a disease that is caused by an inability of the body to control cell division. Like cells, each organ system has a set of specific physiological responsibilities. The term physiology simply refers to the normal function of a cell, organ, or structure. Cancer begins when a cell, or a small group of cells, disregards their genetic programming, loses their specialization, and begins to divide uncontrollably

1. Why have cancer deaths gone down in the US overall?

a few decades ago a cancer diagnosis was often a death sentence, today, for many types of cancer, the 5-year survival rates are over 90%. This is primarily due to better diagnosis and treatment options.

plasma membrane

a microscopic membrane of lipids and proteins that forms the external boundary of the cytoplasm of a cell or encloses a vacuole, and that regulates the passage of molecules in and out of the cytoplasm.

Centrioles

a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.

apoptosis,

a series of events within the cell cause it to fragment and then be engulfed by white blood cells. it is a powerful way that the body has of removing cells that have excessive damage or may no longer be needed by the body.

biopsies

a surgical procedure to remove a small section of tissue to look for the presence of cancer cells.

Genetic Markers

a variation in the pattern of DNA nucleotides. Sometimes these variations occur outside of genes, and sometimes within genes. One way to detect these variations is to use special enzymes, called restriction enzymes, that break the DNA molecule at particular base sequences.

Alkylating Agents

agents are chemicals that integrate into the DNA, typically causing the DNA to break at specific points. agents are very general, they may insert into the DNA of any cell. While the cell does have mechanisms to repair these types of breaks in the DNA, the breaks often introduce mutations, which can have long-term negative effects. could cause leukemia

Topoisomerase inhibitors

also interfere with the ability of the cell to replicate its DNA. They function by disabling a key enzyme of DNA replication called topoisomerase. Topoisomerase helps with the unwinding of the DNA molecule. Without functioning topoisomerase, DNA replication cannot occur during the S phase of the cell cycle.

Internal Radiation treatment

also known as brachytherapy, uses small deposits of radioactive materials that are placed inside the body. This is usually in the form of pellets, which are commonly called seeds. The seeds are placed within the body using needles or catheters. The radioactive material then emits radiation which damages the DNA of the surrounding cancer cells

DNA microarray

also known as gene chips. Microarrays allow physicians or genetic counselors to look for specific mutations or differences in gene expression between cancer cells and normal cells. For cancer diagnosis, researchers may place synthetic DNA on the array that corresponds to known mutations in a single gene (for example, BRCA1), or from a collection of tumor-suppressor genes or proto-oncogenes that are known to be associated with the cancer.

what is the initial test for cancer? what comes after?

an initial mammogram may indicate a suspicious area of the breast. As a result, a PET scan or MRI may be done to determine the extent of the tumor.

Alkaloids

are chemicals that are naturally produced by some plants.rom the Madagascar periwinkle (Catharanthus roseus) work as chemotherapeutic drugs by interfering with the ability of cells to divide. they work by interfering with the ability of the cell to form the spindle fibers that separate the sister chromatids during mitosis Specifically, they inhibit the formation of the microtubules, one of the proteins in the spindle fiber. known to cause nerve damage, so they are often only used in very small doses.

Taxanes

are naturally produced by the yew tree (Taxus sp.). They have a similar function to the alkaloids, except that they prevent the breakdown of the microtubules, thus keeping the sister chromatids attached to the spindle fibers and preventing cell division .known to cause nerve damage, so they are often only used in very small doses.

Be able to recognize key terms related to the stages - metastasis

begins when cells from a tumor enter into the lymphatic vessels (green) or capillaries of the circulatory system (red). b. This allows for the movement of cancer cells from one organ or tissue to another location in the body.

internal radiation

brachytherapy, small deposite of radioactive material in the body

polymerase chain reaction (PCR)

can be used to make copies of specific genes so they may be analyzed to determine if an individual has a specific allele . It is also possible to clone a gene into bacteria and let the bacteria make multiple copies of the DNA.

Describe the tools and key points of early detection related to cancers

cancer diagnoses are divided into 2 categories; the determination of weather an individual has an increased susceptibility to cancer or the cancer is actually detected in body

lymphoma

cancer of the lymph nodes, cells, and tissue of the immune system

Leukemia

cancer of white blood cells in the bone marrow

sarcoma

connective tissue such as bones

transcription

converts the genetic information into an intermediary RNA molecule called messenger RNA (mRNA). first step of gene expression addresses the problem of location by making a copy of the section of the DNA that contains the gene of interest. its purpose is to produce an RNA molecule, called messenger RNA (mRNA) to deliver the genetic instructions to the protein-producing machinery located in the cytoplasm of the cell.

DNA Sequencing

determines the order (or sequence) of nucleotides in a given segment of DNA, which may be a gene associated with a genetic disease. By determining the exact sequence of nucleotides, scientists are able to identify specific alleles associated with a disease. involves attaching dyes to the nucleotides and detecting the different dyes via a laser in an automated sequencing machine.

Plant - Chloroplast

double membrane; site of photosynthesis (glucose synthesis)

Metaphase

each of the homologous chromosomes aligns along a central line in the cell. This will allow one of the sister chromatids to move toward each of the new cells, ensuring that the new cells have the same genetic information.

• Explain the process by which DNA is replicated in the cell and the importance of the polymerase reaction.

each of the strands acts as a template for the construction of a new daughter strand

Summarize the different methods of using radiation to treat cancer - internal vs external

external uses x-rays or gamma rays to target a specific area of the body. while Internal uses small deposits of radioactive material material placed in the body

Mitosis

first part of the Mphase occuring in a series of steps: prophase> metaphase>anaphase> telophase. These steps serve to organize the chromosomes so that the sister chromatids may be separated and moved to each of the newly forming cells.

meisosis 1

follows the same series of steps as mitosis: prophase, metaphase, anaphase, and telophase. The difference is that in the first round of meiosis, called _________, the homologous chromosomes have paired with one another

In vivo gene therapy

gene is delivered directly into the body. occurs inside the body

Ex vivo gene therapy

gene is inserted into cells that have been removed and then returned to the body. occurs outside the body

• Distinguish between a genetic and infectious disease.

getting the flu, or a cold, or the measles, is not something that is inherited by your children. But some diseases, such as sickle-cell disease and cystic fibrosis, may be passed on from one generation to the next.

• In what ways are the circulatory, respiratory, and lymphatic system linked?

he circulatory system, is responsible for delivering oxygen and nutrients to all of the cells of your body, and removing waste materials. In most cases, every cell of the body is located close to a capillary, the small structures of the circulatory system where the majority of this exchange occurs. Because the circulatory system and the respiratory system work closely together in the exchange of gases, it should be no surprise that sickle-cell disease also influences the efficiency of the respiratory system. As we discussed earlier, air entering the respiratory system makes its way down a series of tubes (larynx, trachea, bronchus, and bronchioles) before ending up in the small air sacs called alveoli The immune and lymphatic systems are responsible for protecting the body from foreign pathogens. Like most body systems, anemia has an impact on the ability of the cells and organs of the immune system to perform their function.

G1 checkpoint

hese play a major role in determining whether the cell is prepared for DNA replication in the S phase of the cell cycle.If the proteins that regulate the G1 checkpoint determine that the cell is not ready to pass into S phase, which in the case of the G1 checkpoint is due to excessive damage to the DNA, then the cell may be placed into the G0 phase

genetic testing

his typically uses a simple blood test for the purpose of detecting the presence of specific mutations in known cancer genes (such as BRCA1). Following the blood test, DNA is isolated from white blood cells and subjected to a process called the polymerase chain reaction (PCR) to make multiple copies of the genes of interest for additional studies.

• Describe the role of meiosis in sexual reproduction.

humans have two copies of each chromosome (diploid, or 2n). During sexual reproduction, the organs of the reproductive system produce gametes (eggs and sperm) that contain only one copy of each chromosome (haploid or n).During sexual reproduction, a haploid sperm fertilizes a haploid egg, and in the process produces a diploid zygote. This single-celled zygote divides by mitosis to produce a multicellular diploid individual.a form of cell division that reduces the chromosome number of the daughter cells from diploid to haploid, and introduces variation into the daughter cells. It consists of two rounds of cell division, and results in the formation of four haploid cells . In humans and other animals, these haploid cells will become the egg and sperm cells.

If the initial blood tests suggest the presence of cancer in the body, a physician may order a

imaging scan-

translation

interprets the genetic information, from the mRNA, into the structure of a protein. While there are only four different bases in the mRNA (A, C, G, U), 20 different amino acids can be used in the building of a protein.

dna replication

involves the following steps: The helicase enzyme breaks the hydrogen bonds between the complementary paired base nucleotides in each strand. The DNA polymerase enzyme begins to synthesize new strands of DNA using the separated strands as templates.. The two strands of DNA are orientated in opposite directions. However, DNA polymerase can only make new DNA strands in one direction. On the leading strand, the DNA polymerase follows directly behind the helicase enzyme. On the lagging strand, the DNA polymerase makes short segments of DNA, called Okazaki fragments, which are then connected together by a DNA ligase enzyme. the end result of __________ are two sets of identical DNA, commonly called sister chromatids.

Describe how genome editing may be used to treat a genetic disease

involves the targeting of specific sequences in the DNA for removal or replacement. Using the CRISPR system as a form of molecular scissors, new nucleotides may be inserted at specific locations on the DNA. Because the gene for sickle-cell disease is known, and it is the result of a single mutation, this genetic disorder is an ideal candidate for genome editing.

immunotherapy

involves the use of the body's immune system to identify and eliminate cancer cells.

Immunotherapy

is designed to convince the immune system to identify cancer cells as foreign, and then use existing treatment methods to target them for destruction.

allele

is simply a variation of a gene. These variations are usually due to small changes in the nucleotide sequence within the gene. Often, these_______ have no real effect on the resulting protein, but sometimes they can cause a change in the structure of a protein, and thus its function.

angiogenesis

is the formation of new blood vessels. This process involves the migration, growth, and differentiation of endothelial cells, which line the inside wall of blood vessels. The process of angiogenesis is controlled by chemical signals in the body

gene expression

is the series of events within a cell that takes the information within the DNA and produces the protein (or RNA) molecules.

Genome editing

is the targeting of specific sequences in a DNA molecule for editing.

1. Differentiate how cancerous cells are different from normal cells. What "special" capabilities do they exhibit?

is their ability to continuously divide. This unregulated cell division has the potential to disrupt the normal function of the cells, tissues, and organs of the body, causing the physiological symptoms of the disease. Normally, cells in a given tissue have a distinct appearance, and it is usually difficult to pick out any differences between individual cells. This is because, through the process of cell division, these cells are genetically identical and are carrying out the same genetic instructions in the tissue. However, cancer cells often look very different than their surrounding neighbors. In many cases, they have an irregular shape. immortal and less specialized

our immune system

is well adapted in the identification of foreign infectious agents, such as bacteria and viruses. The cells and organs of the immune system work by identifying "self" versus "nonself," and then targeting anything that is "nonself" for destruction. Therein lies the problem with cancer. As we have previously learned, cancer is actually our own cells that have lost their genetic identity and begun to divide rapidly. Therefore, cancer cells generally can escape the attention of the immune system.

complete blood count (CBC)

looks for the presence of normal blood cells in their correct amounts. Some cancers, especially blood cancers, may elevate the number of white blood cells in the body. If metastasis has occurred, it may also be possible to detect the presence of tumor cells in the blood. This can give a physician an idea of the extent of the cancer in the body, and the type of body scan that needs to be conducted

Tumor Suppressor Genes

make proteins that stop cell division and kill cells. they are the 'stop/break' of the cell cycle

breast cancer

malignant tumor of the breast effects 1/8 of women in the US. if an individual has a mutation in one of their copies of BRCA! they may be susceptible to breast cancer bc a mutation that inactivates the other copy of BrcA1 in a cell could leave w/o a functioning tumor suppressor gene.

chemotherapy

means the use of a drug to treat a disease. Fatigue, nausea, loss of appetite, and hair loss are a few of the more common side effects. chemotherapy works by targeting the characteristics of fast-growing cancer cells.chemotherapy affects all of the cells of the body. Because it operates across the entire body, it is effective in treating or preventing metastasis. However, as we will see, it can interfere with any type of rapidly dividing cells, such as the cells lining our digestive system and blood cells.

Associated with sexual reproduction

meiosis

Chromosomes number in the daughter cell is half the parent cell

meiosis

Crossing over occurs

meiosis

Daughter cells are genetically unique cells; different from parent cell and each other

meiosis

Down's Syndrome & other chromosomal # developmental abnormalities can occur

meiosis

Ending daughter cells are haploid (1n)

meiosis

Occurs in testes and ovaries

meiosis

Sister chromatids separate

meiosis and mitosis

Tetrads form

meiosis and mitosis

Lysosome

membrane-bound organelles with roles in processes involved in degrading and recycling cellular waste, cellular signalling and energy metabolism. Defects in genes encoding lysosomal proteins cause lysosomal storage disorders, in which enzyme replacement therapy has proved successful.

Daughter cells are identical to parent cell and each other

mitosis

Occurs in body cells only

mitosis

Only 2 daughter cells are produced

mitosis

Only one cell division occurs

mitosis

M phase

mitosis stops until chromosomes are properly aligned. Following the S phase, the cell, with its duplicated chromosomes, enters into one final growth phase before proceeding into the M phase of the cell cycle

Over the past few decades

mortality rates from cancer have decreased by over 21%

Mammogram

most common form of imaging scan.A mammogram is an X-ray of the breast tissue (and surrounding tissues 2 dif types

codominance

occurs when two dominant alleles are expressed in the phenotype of an individual. Type AB blood in humans is an example

external radiation

process of administering radiation to the patient via a radiation machine located outside the body

Antimetabolites

re chemicals that have a similar structure to a compound normally used by the cell, but are different enough that the cell cannot use them effectively. Chemotherapeutic antimetabolites typically mimic the nucleotides used in the building of a DNA molecule. They differ enough that they interfere with the DNA replication machinery during the S phase of the cell cycle.

radiation

refers to the movement of energy in the form of either waves or particles.In general, the longer the wavelength, the less energy is present in that form of radiation, so radio waves have less energy than X-rays.works by damaging the DNA within a cell, with the intent of causing it to slow down or stop cell division. Unlike chemotherapy, radiation therapy can be directed against specific tissues and cells of the body. However, because radiation therapy is more targeted, it is not as effective in destroying cancer cells that have metastasized to other areas of the body.

meiosis 2

s very similar to mitosis, except that the cells starting the process are haploid (n). Notice that at the end there are four daughter cells, each of which has only a single copy of each chromosome (haploid, or n). Also, the daughter cells are different genetically from each other.

Melanoma

skin cancer

proto-oncogenes

speed up cell cycle. assciate signaling pathways: groth hormones interact with the target cell receptor. it becomes oncogene when mutations cause them to be stuck on and only a single mutatio is require for this

Telaphase

spindle fibers disappear as a new nuclear envelopes from around the daughter chromosomes. each nucleus contains the same number and kinds of chromosomes as the orginal parent cell

G2 phase

stage of interphase in which cell duplicates its cytosol and organelles and mitosis will not occur until DNa HAS REPLICATED

plant- cell wall

strong, protective structure made from cellulose fibrils

• Explain the physiological impact of sickle-cell disease on the body.

structure indicates function." The structure of hemoglobin suits its function in gas exchange well. Because red blood cells are responsible for delivering hemoglobin and oxygen to every cell of the body, any change in the structure of hemoglobin, and thus the red blood cell itself, will have consequences throughout the body. Sickle-cell disease affects the structure and function of red blood cells, as well as several body systems.

genes involved in transmitting information to the next generation.

the basic unit of inheritance. Ultimately, the purpose of cell division is to pass a copy of a cell's genes to the next generation of cells, and the purpose of sexual reproduction is to pass an individual's genes onto the next generation.

During interphase

the cell performs all of its normal functions, but it is also preparing for the next round of cell division.The two growth phases (G1 and G2) are separated by S phase, a period during which the DNA in the nucleus is replicated to prepare for division into two new cells. Some cells enter into a resting phase (G0), during which they are no longer participating in the cell cycle. As we will see next, there are a series of checkpoints during which the cell assesses whether it should be proceeding to the next phase of the cell cycle.

G0 phase

the cell will attempt to repair the damage to the DNA. If that is not possible, then the cell may be targeted for cell death using a process called apoptosis.

prophase

the genetic material condenses into compact chromosomes, and spindle fibers (which are actually part of the internal framework of the cell) form from the centrioles to help align the chromosomes.

Cytoplasm

the material or protoplasm within a living cell, excluding the nucleus.

Polymerase Chain Reaction

the principles of DNA replication could be used to copy specific segments of DNA, such as the hemoglobin gene, in large quantities. consists of three basic steps: Denaturation (95°C), where DNA is heated so it becomes single-stranded. This replaces the helicase enzyme in DNA replication. Annealing (between 50°C and 60°C) where a primer binds to each of the single DNA strands. This primer was designed to specifically target a short segment of the DNA molecule. Extension (72°C) where a DNA polymerase adds complementary bases to each of the single DNA strands, creating double-stranded DNA. The DNA polymerase used in PCR must be able to handle these high temperatures of the denaturation stage. Mullis discovered that a polymerase found in hot spring bacterium Thermus aquaticus (commonly abbreviated as Taq) was stable at these temperatures.

cytokinesis

the second part of the M phase, divide the organelles and cytoplasm into two new daughter cells. This is done by pinching the plasma membrane inward until the daughter cells form around the two new nuclei, begins before end of telophase

anaphase

the sister chromatids separate and migrate to opposite sides of the cell.

1. Summarize how researchers are investigating new methods of fighting cancer - immunotherapy.

the use of the body immune system to identify and eliminate cancer cells. Designed to convince the immune system to identify cancer cells as foreign invaders.

incomplete dominance

where the dominant allele does not completely mask the recessive allele. There are several examples of this in humans, including a disease called familial hypercholesterolemia. EX: Children born with semi-curly or wavy hair