Bio Midterm 2

Order of gene expression

1. Located in the nucleus, DNA serves as the template for gene expression. 2. The genetic information 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.

steps of mitosis

1. Prophase 2. Metaphase 3. Anaphase 4. Telophase 5. Cytokinesis

What are the 5 characteristics of life?

1. obtain and use energy from the environment 2. reproduce, grow, and develop 3. sensitivity and response to stimuli 4. capable of regulation 5. evolution

if a breast cancer patient has not responded to treatment and the cancer has spread to the brain, the patient is classified as have Stage ___ cancer

4

As cancerous cells accumulate mutations, the cells will continue to divide rapidly. This uncontrolled division results in...

All of the answer choices are correct

genetic markers

An inheritance of a variation in the pattern of DNA nucleotide means that a person may be susceptible for a certain disease

Which of the following would be detected in a blood test that would indicate the immune system is responding to cancer?

Antibodies

telophase

As new chromosomes reach the poles, the nuclear envelopes re-form, and the chromatin decondenses.

Which of the following scanning tools is a special type of X-ray that is used to determine if the cancer has spread?

CT scan

Which characteristic corresponds with Stage 2 of breast cancer?

Cancer begins invading more lymph nodes and tissue

G2 phase

Cells prepare to divide and check that the proper steps have occurred for division

Which of the following statements concerning chromosomes is/are true? Select all that apply.

Chromosomes are composed of DNA and packaging proteins called histones so they may fit tightly into the nucleus of a cell.Located on each chromosome are segments of DNA known as genes or units of inheritance that code for functional products.LocatedDNA replication occurs prior to the cell cycle, in which copies of each homologous chromosomes are made and each of these copies are called sister chromatids.After replication, sister chromatids, which are identical copies of a chromosome, contain identical allele combinations.

cytokinesis

Cytoplasm and the organelles are divided equally

_____ is tightly packed up to fit in the nucleus of every eukaryotic cell

DNA

mutations in tumor-suppressor genes and in proto-oncogenes can result in cancer. if both are mutated,

DNA damage will go unrecognized and cell division will increase

direct DNA sequencing

Determining the exact sequence of nucleotides, scientists are able to identify specific alleles associated with a disease

the newer _______ _______ _______ model views identity development as two processes: exploration and consideration of commitments

Dual Cycle Identity

S phase

Duplicated chromosomes are separated during this phase

(T/F?) In breast cancer patients, lymph nodes are biopsied to determine the size of the tumor.

False

at which checkpoint is DNA assessed for accuracy before cell division?

G2

there are three checkpoints during cell division. which checks for DNA replication?

G2

DNA microarrays

Identifies a specific allele or patterns of gene expression between two cell types, tissues, or individuals

cell division occurs in ____ phase

M

homologous chromosomes

Pair of chromosomes that are the same size, same appearance and same genes.

M phase

Phase in which cells duplicate the genetic material

Centromere

Region of a chromosome where the two sister chromatids attach

prophase

Replicated chromosomes condense and attach to the mitotic spindle.

G0 phase

Resting stage assumed by cells that exit the cell cycle

Chemotherapy can interact with different phases of the cell cycle. What are the main phases that these drugs target?

S, G2, and M

Which of the following scanning tools is used to look for abnormalities in the breast that could be associated with cancer?

Screening mammogram

cytokinesis

The entire cell physically divides into two daughter cells.

pedigree

The historic way in which an individual was determined to be susceptible to a genetic disease

metaphase

The mitotic spindle aligns the replicated chromosomes at the center of the cell.

anaphase

The sister chromatids separate and become individual chromosomes that begin to move toward the poles of the cell.

antimetabolites

These chemicals have a similar structure to a compound normally used by the cell. By mimicking the structure, they can prevent DNA replication machinery from copying the DNA during the S phase.

alkylating agents

They alter the DNA molecule and prevent the strands of the double helix from linking together. This causes breakages in the DNA strands and affects the ability of the cancer cell to replicate. They are effective during every phase of the life cycle of a cancer cell and are useful in treating slow growing cancers.

alkaloids and taxanes

They are naturally produced by plants. These agents cause the inhibition of mitosis by interfering with spindle fibers, which prevents the separation of sister chromatids during anaphase.

Topoisomerase inhibitors

They interfere with an enzyme that is necessary for DNA synthesis. By disabling the function of the enzyme, the cell is unable to replicate the DNA during the S phase.

(T/F?) Negative feedback works to maintain homeostasis within the body

True

G1 phase

Two new daughter cells grow in preparation for division

karyotype

Visualizing an individual's autosomes and sex chromosomes to determine if there are any changes on the chromosomes

Cancer

a disease in which the body is unable to control the division of cells

exploration "crisis"

a period of development in which the adolescent is exploring alternatives

commitment

a personal investment in an identity

lysosomes

act as floating garbage disposals for cells, digesting and recycling cellular waste products and consumed material

nucleus

acts as the genetic control center of the cell stores hereditary information

G2 checkpoint

after the cell has undergone synthesis, the cell checks to make sure the DNA has been replicated without errors

M phase chemo includes

alkaloids and taxanes

Cell Cycle nonspecific agent chemo includes

alkylating agents

translation; where does it occur?

amino acids in a polypeptide are sequenced as specified by the template DNA strand; occurs in cytoplasm

Interphase - S phase chemo includes

antimetabolites topoisomerase inhibitors

nucleolus

area of the nucleus where ribosomal subunits are assembled

22 pairs in humans, do not differ between males and females

autosomes

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

working together, the circulatory and respiratory system function in circulating _____ and oxygen throughout the body

blood

Alkalyting agents work by

breaking the DNA and introducing mutations

Which characteristic corresponds with Stage 3 of breast cancer?

cancer extensively spreads to nearby tissue

finally, the cells utilize the oxygen for their specific activities; this is called _____ _____ or cellular respiration

cellular metabolism

prophase is a step of mitosis. what key event happens during prophase?

chromosomes condense

as blood moved in and out of the lungs through the pulmonary arteries and veins that connect to the heart, the ____ system is responsible for delivering oxygen to the tissues of the body and removing waste materials

circulatory

sickle red blood cells ____ together, blocking small blood vessels and causing painful and damaging problems

clump

what causes cancer?

defects in genes that regulate cell growth and division

the _____-_____ DNA molecule wraps around packing proteins called ______, forming the nucleosome

double-stranded, histones

M checkpoint

during this checkpoint, the cell cycle stops and determines if the chromosomes are properly aligned to ensure equal division of genetic materials

gene expression

each cell has specific instructions about which genes to express and how much of that protein to produce

Key changes in identity are more likely to take place in ______ _____ than in ________

emerging adulthood, adolescence

Telomeres

ends of chromosomes, do not contain protein-coding DNA

(T/F?) each time the cell divides, the telomerase enzyme shortens the length of the chromosomes

false

(T/F?) mutations in DNA can result in cancerous cells. these cells are structurally altered but their functions remain normal

false

transcription; where does it occur?

genetic information is passed from DNA to mRNA; occurs in the nucleus

sperm cells are _____ cells, and each cell contained only one set of 23 chromosomes

haploid

review the following statements about hemoglobin. which of the statements is true?

hemoglobin, globular protein with an embedded heme group, efficiently binds to oxygen from the lungs and releases it near cells that are performing cellular respiration

as air moves in and out of the respiratory system, ______ a protein contained in the _____ of the circulatory system, interacts with and binds to oxygen in the lungs enabling its function gas exchange

hemoglobin, red blood cells

the structure of the ______ suits its function in gas exchange. because red blood cells are responsible for delivering hemoglobin and oxygen to every cell of the body, any change in the _____ of the hemoglobin will change the _____ of the red blood cell

hemoglobin, structure, function

steps of the cell cycle

interphase, mitosis, cytokinesis

identity achievement

involves the adoption of a set of beliefs and values, recognition of one's strengths and weaknesses, and a commitment to a vocational direction

each gene has a specific location, or _____, on a chromosome

locus

ribosomes

make proteins

how could mutations lead to problems in enzyme pathways? how do problems in enzyme pathways lead to cancer?

mutations can mean a non-functioning protein - even one non-functioning enzyme blocks the pathway; cancer occurs when the pathway in question relates to cell division

_______ makes a single viable egg and three haploid polar bodies in the ovaries

oogenesis

centrioles

organelles that make the spindle fibers out of microtubules

spindle fibers

organize chromosomes during cell division, split them evenly between organelles

the body cells need a continuous supply of _____ for the metabolic processes that are necessary to maintain life

oxygen

cytoskeleton

provides shape and support controls intracellular traffic and enables...

with sickle cell disease, the hemoglobin in red blood cells is abnormal. this in turn changes the shape and damages the _____ ____ ____, the major type of cell in the circulatory system

red blood cells

G1 checkpoint

regulated by growth factors, this checkpoint determines if the cell is ready to replicate the DNA

______ is the sequence of of events that results in the exchange of oxygen and carbon dioxide between the atmosphere and the body cells

respiration

what enzyme to cancer cells use to avoid shortening of telomeres?

telomerase

telomere length can change with age and the type of cell. which of the following correctly describes telomere length?

telomeres are the longest in stem cells

characteristics of life

the ability to reproduce, the ability to acquire materials and energy, the ability to respond to the environment

Chromosomes in a homologous pair

the same length and shape and carry genes controlling the same inherited characters

which of the following statements best describes the relationships between genomes, genes, and proteins?

there is one genome, it consists of many genes that encode for multiple proteins

what happens to telomeres as the cell undergoes more and more divisions?

they get shorter (too short = apoptosis)

chromatin/chromosomes

thin fibers of DNA, which carry all hereditary information

sister chromosomes

two identical chromosomes which form when DNA replicates attached at the centromere until they seperate during cell divison

how is cell specialization achieved?

when cells only express the DNA they need to do their specialized job - cell division and specialization ->

if a person has a cancer that interferes with organs of the urinary system, that person may have trouble

with regulating the water-salt balance of the blood

In order for cancer to develop, which of the following events must occur? Select all that apply.

- a cell malfunctions and unregulated cell division occurs - genetic mutation causes a cell to lost its normal genetic programming and control mechanisms

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

endomambranes (EMS)

- produce and modify molecules for export to other parts of the organism - break down toxic chemicals and cellular by-products

Which of the following correctly describes the process of angiogenesis? Select all that apply.

- 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

______ are further condensed to form _____ during the process of cell division

nucleosomes, chromosomes

sickle cell disease also prevents the hemoglobin in red blood cells from carrying ______ to all parts of the body. as oxygen concentration of the body drops in an individual, a condition called _____ develops.

oxygen, anemia

parents as managers

parental monitoring and information management

How are cancers named?

reveals which organ or type of cell in which the cancer originated in

______ attached adolescents are less likely to have emotional difficulties and to engage in problem behaviors, juvenile delinquency, and drug abuse

securely

identity

self portrait composed of many pieces

1 pair in human, carry sex-determining genes, includes the X and Y chromosome

sex chromosomes

anaphase is a step of mitosis. what key event happens during anaphase?

sister chromatids are pulled apart

What is the MAJOR cause of the most common cancer in humans?

smoking

male gametes are called

sperm cells

_______ creates four sperm from a primary spermatocyte

spermatogenesis