Biology Exam 2

Genome editing

- technology is a method to make specific changes to the sequence of a DNA molecule. -allows scientists to alter an organism's DNA, is being applied to research on cancer to hopefully decrease the risk of cancer by correcting mutations and restoring the function of a cell.

In order for cancer to develop, which of the following events must occur?

-A cell malfunctions and unregulated cell division occurs. -Genetic mutation causes a cell to lose its normal genetic programming and control mechanisms.

Which of the following describes how physicians stage a patient diagnosed with breast cancer?

-A numerical staging system describes the degree to which cancer has spread. -Staging helps describe where cancer has spread and whether it is affecting other parts of the body. -Staging helps describe where a cancer is located.

Stage 3B

-A tumor has spread to the chest wall behind the breast. In addition, the factors that contribute to assigning this stage include spread to the skin causing swelling, inflammation, or ulcerated wounds. It may have spread to as many as nine lymph nodes near the breast

Select all of the following examples of how cancer can disrupt organ function.

-Brain cancer may place pressure on areas of the brain that regulate bodily functions and disrupt their regulation. -Cancer in the bone marrow may prevent white blood cells from forming, reducing the ability of the immune system, and leaving the body open to infection. -Blood is re-routed and nutrients are directed to the tumors in the breast, leaving fewer resources for normal cells.

Which of the following reasons would explain why cancer cells are able to escape the immune system?

-Cancer cells are not recognized as nonself cells and can continue to divide without attracting the attention of the immune system.

cancer cells

-Disregard their genetic programming -Lose their specialization -Divide uncontrollably

A cell is the smallest unit of biological organization that has all of the characteristics of life. Which of the following are considered characteristics of life?

-Passes on genetic information to offspring -Acquires materials and energy to manufacture cellular components -Adapts to changes in its environment

Which of the following correctly describes the process of angiogenesis?

-Promotes the growth of local capillaries to grow toward the tumor -Allows for oxygen to reach the tumor -Allows for nutrients to reach the tumor

external radiation

-Uses a machine to delivery beams of radiation - gamma rays and X-rays are used because these contain the highest levels of energy. -Allows for precise delivery of radiation

Stage 3A

-With a tumor in the breast, cancer is found in more than four nearby lymph nodes -It may also mean a breast tumor is larger than 5 cm, and the cancer has spread to less than four nearby lymph nodes

Homeostasis

-adjustments in physiological processes to respond to changes that disrupt the internal environment -maintaining a narrow range of internal conditions to optimize the body's performance -utilizing negative feedback mechanisms to maintain internal conditions -mechanisms in place to regulate temperature, blood sugar, pH, and levels of chemicals in the blood

Stage 1B

-cancer HAS spread to surrounding lymph nodes

Stage 1A

-cancer cells HAVE NOT spread to lymph nodes

Stage 1A and 1B

-cancer is evident and has spread to surrounding tissues -tumor is small, less than 2 cm

Stage 4

-cancer that has metastasized beyond the breast tissue and nearby lymph nodes and into other areas of the body. -the most advanced and life-threatening stage of breast cancer -considered incurable, current medical advances have provided a number of treatments that Stage 4 breast cancer may respond to and thereby extend the life of the patient for several years.

Radiation therapy

-form of cancer management in which high-powered energy beams are used to kill cancer cells. -another type of cancer treatment, uses energy to destroy cancer cells, shrink tumors, and ease cancer symptoms. -can be directed against specific tissues and cells of the body. There are two types of radiation treatment.

Appearance of cancer cells

-irregular shaped cells -look different than surrounding cells due to large dark nuclei -cells are immortal due to enzyme telomerase that continues to lengthen the ends of the telomeres

Internal radiation treatment

-is a treatment in which a source of radiation is put inside the body. Also known as brachytherapy, the treatment involves a seed that emits radioactive materials near the tumor to damage the DNA of the cancer cells. -is a type of cancer treatment that delivers a high dose of radiation in direct contact with the tumor and helps spare nearby tissues -uses a pellet, known as a seed, to be placed in the body using a needle or catheter

Stage 0

-no evidence of cancer cells -cancer is evident but has not spread to surrounding tissues

Radiation

-refers to the movement of energy in the form of either waves or particles. -At high doses, radiation can be used as a form of treatment to kill cancer cells or slow their growth by damaging the DNA -The response to radiation therapy is not immediate, and it takes days or weeks for the cells to stop dividing and die. -ability to damage healthy cells. -not effective at destroying cancer cells that have metastasized since the process is more targeted against specific areas.

Appearance of normal cells

-small, regular shaped cells -look similar to surrounding cells since they are genetically identical -fixed lifespan due to length of telomeres at end of chromosome

cancer

-starts with changes at the genetic level of individual cells, which may cause some cells to lose control and divide rapidly and uncontrollably. -Cancer is a disease that begins with changes in the body at the cellular level due to abnormal cells dividing in a disorderly manner.

Stage 3

-the cancer has spread farther into the breast and surrounding tissues -divided into three levels based on the size of the tumor and the degree in which the cancer has spread into the surrounding tissues and lymph nodes

Stage 2B

-tumor is 2-5 cm in size and cancer cells have been detected in lymph nodes

Stage 2A

-tumor is smaller than 2 cm and cancer cells have been detected in lymph nodes -tumor cannot be detected but cancer cells have been detected in lymph nodes -tumor is 2-5 cm in size but has not spread to lymph nodes

CRISPR (genome editing)

-used to modify DNA by either removing nucleotides and inactivating genes or inserting new nucleotides and changing the function of the gene. -Specifically, for cancer treatments, the CRISPR system targets DNA sequence for fusion proteins, proteins in which the genes have been mutated and are causing unregulated growth of a cell. -In doing so, researchers have been able to inactivate cell-cycle control genes that have lost their ability to function, also known as oncogenes, and reduce the size of tumors.

chemotherapy

-which usually exposes the whole body to cancer-fighting drugs,

To determine the stage of cancer, the oncologist will answer the following questions using a variety of methods:

1) What is the size of the tumor? 2) What is the degree to which it has invaded nearby tissues? 3) Is the cancer present in nearby lymph nodes? 4) To what extent has the cancer metastasized to other organs of the body?

Stages of Gene Expression

1. Located in the nucleus, DNA serves as the template for gene expression 2. The genetic expression is transcribed from DNA into a complementary strand of mRNA 3. mRNA, an intermediate molecule, leaves the nucleus to the ribosome. 4. In the cytoplasm, mRNA and its codons are translated at the ribosome and specify a tRNA carrying specific amino acids 5. The amino acids bind together to form a growing protein chain that eventually breaks off from the ribosome.

Stages of TRANSCRIPTION

1. RNA polymerase identifies the gene to be expressed. 2. RNA polymerase exposes the nucleotide bases of the gene by unwinding the double helix. 3. RNA polymerase uses one strand of DNA, called the template strand, to produce a complementary RNA molecule. 4. The RNA polymerase and the complementary RNA strand are released along with the DNA, reforming a double helix.

Stages of TRANSLATION

1. The mRNA molecule arrives at the ribosome in the cytoplasm. 2. The first codon on an mRNA molecule is read. 3. A tRNA molecule with a complementary base sequence to the mRNA brings the first amino acid. 4. As to codons on the mRNA molecule are read, each corresponding amino acid is added to the growing protein chain. 5. Once the information in the mRNA is processed, the ribosome and mRNA separate and the chain of amino acids is released.

Steps to create vaccine

1. white blood cells are removed from body and are stimulated to divide 2. the white blood cells are exposed to an antigen found only on the surface of cancer cells 3. the white blood cells uptake some of that antigen and are inserted back into the body 4. acting as a messenger, the white blood cells stimulate the immune system to produce cytotoxic T cells 5. the cytotoxic T cells seek out cells with the antigen and destroy those cancer cells

What is the first step to determine if a patient is susceptible to a certain type of cancer?

A blood test to detect the presence of a specific mutation related to known cancer genes

Mammogram

An X-ray picture of the breast to look for early signs of breast cancer

__________carry nutrients and oxygen to cells and also remove waste materials.

Capillaries

Some organs in the body play an important role in regulating the chemical composition of the body's fluid by retaining the proper amounts of solutes. Examples are:

Example 1: Calcium homeostasis, which refers to the maintenance of a stable concentration of calcium ions in the body's fluids, is critical for the function of all body organs. -If left undetected and untreated, high levels of blood calcium may lead to a coma and death. -Bone cancer may disrupt the calcium homeostasis by causing bone to break down, releasing excess calcium into the blood, and blood calcium levels to rise. Example 2: The liver, one of the largest organs in the body, is an important metabolic organ and regulates most chemical levels in the blood. It aids in the process of converting the nutrients in our diets into substances that the body can use, stores these substances, and supplies many different chemicals to the body when needed. -Liver cancer, therefore, can easily disrupt the chemistry of the body.

___________ vessels are responsible for removing excess fluid from the tissues and participate in the immune response.

Lymphatic

Positron emission tomography (PET)

Radioactive material injected into the body to act as a tracer

_________ is the process of finding out how much cancer is in a person's body and where it's located.

Staging

Failing to respond to the signals that control normal cell behavior and growth, cancer cells grow and divide in an uncontrolled manner, invading normal tissues and organs and eventually spreading throughout the body

TRUE

Computerized tomography scans (CT)

Taken as a series of X-ray pictures of the body at different angles to create a multi-dimensional view of the internal organs

Stage 3C

The cancer has spread to the area of the collar bone or to more than ten lymph nodes.

Imaging scans

Used in diagnosing cancer after an initial blood test suggests the presence of cancer in the body

Magnetic resonance imaging testing (MRI)

Uses powerful magnets and radio waves to produce detailed, computer-generated pictures of the body

These cancer cells will undergo ___________ and form new tumors in a different location.

angiogenesis

A difference between cancer cells and normal cells is that cancer cells __________

are less specialized and continue to divide because they no longer function as part of a tissue or organ.

The main difference between Stage 0 and Stage 1 cancer is that in Stage 1, the cancer cells have

begun to spread to a few lymph nodes.

Homeostasis: By ________ channels like ducts, blood vessels, or lymphatic vessels, this overcrowding disrupts the normal operations of the surrounding organs because it prevents the ability to transport materials.

blocking

For cells to become ____________, cells have to undergo changes that make them different from other cells of the body.

cancerous

For multicellular organisms, this single cell will undergo rapid ___ ________and divide over and over again until it becomes an adult body.

cell division

Cancer is a disease that occurs at the __________ level of biological organization of living things

cellular

Homeostasis: In other instances, the_________ of normal operations of an organ can lead to a change in the chemical composition of the body's fluid.

disruption -Over time, the reduction in function of the organ will cause the organ system to shut down and death may occur.

Although there are many different forms of cancer, it is presumed that cancer is a disease caused by the combined effects of both genetic and ________________ ___________

environmental factors

One, cancerous cells accumulate mutations that ignore the regulatory mechanisms of the cell cycle and cannot instruct them to stop dividing and to die. Therefore, cancer cells do not have a __________ lifespan.

fixed

The production of cells is closely regulated by a variety of ____________ and genetic mechanisms within the cell to ensure that only the correct type and number of new cells are produced.

hormones

As the number of cancer cells ____________, they may spread and invade nearby tissues and organs, disrupting their physiological processes and their ability to survive.

increases

Immunotherapies include the use of chemical signals to activate the immune system, such as __________, which are proteins that signal white blood cells to be active in an immune response.

interleukins

Two, cancer cells appear ___________ in shape, and the nuclei of cancer cells are distinctly different from normal cells. The large, dark nuclei of cancer cells are due to the accumulation of DNA.

irregular

When the genetic programming of a small group of cells becomes faulty, the cells start to _____ their specialization.

lose

As more mutations accumulate in a cell, there is a _______ of function, and they no longer function as part of the surrounding tissue.

loss

The generalized ________ of control over cell reproduction exhibited by cancer cells is the result of accumulated abnormalities and is reflected in several aspects of cell behavior that distinguish cancer cells from their normal cells.

loss

Cancer cells might have traveled through your _________ system to different organs such as the lungs, heart, liver, or brain

lymphatic

If a _____________ tumor comes into contact with the transport system of the body, this allows for the movement of cancer cells from one area of the body to other locations in the body. The spreading of cancer cells to new areas in the body is called _________.

malignant, metastasis

Cancer cells may develop the ability to migrate to other parts of the body and undergo the process of angiogenesis and form new tumors. This process is called __________ and represents a serious threat to the body.

metastasis

After a general physician makes the initial diagnosis of cancer, the actual staging of cancer is done by an ____________

oncologist

As the cells divide, these replicates of the original cell will receive signals from the environment and turn on ____________ pathways that instruct the cells to turn on certain sets of genetic instructions and turn off others.

physiological

In doing so, the cells become___________, which allows tissues and organs to form and have specific roles within the body.

specialized

Both capillaries and lymphatic vessels are part of the __________ system of the body.

transport

Which term describes an overgrowth of abnormal cells that serves no useful purpose?

tumor

With no genetic control, the cells start to divide ____________ and the cells undergo more rounds of division than they normally would, making cells prone to replication errors.

uncontrollably

______________ cell division is a hallmark of cancer.

unregulated

External radiation treatment

uses a machine to aim beams of energy to specific parts of the body. The most commonly used type of treatment, radiation types vary from X-rays to higher energy gamma rays.

__________ aid the immune system in mounting attacks against cancer cells by targeting antigens only found on the surface of cancer cells.

vaccines