Exam 4 Flashcards
Describe the characteristics of cancer cells that distinguish them from normal cells. (7)
- Are not differentiated; don’t contribute to bodily functions.
- Have abnormal nuclei and cell shape.
- Unlimited replication.
- lack contact inhibition and divide even when crowded
- disregard regulation by growth factors
- cause blood vessels to grow/make new ones for nutrients
- may metastasize.
Distinguish between a proto-oncogene and a tumor suppressor gene with regard to their effects on the cell cycle
proto-oncogene: cause cancer when mutated. They promote cell cycle and prevent apoptosis.
Tumor suppressor: inhibit cell cycle and promote apoptosis. Cannot do this when mutated.
identify the common types of cancers and the body system with which each is associated
Carcinoma: epithelial tissues. Inner/outer coverings of organs.
Sarcoma: muscles and connective tissue, and bone
Leukemias: blood
Lymphomas: lymphoid tissue
Blastoma: composed of immature cells.
Explain how heredity, the environment, certain viruses, and diet contribute to cancer.
Heredity: traits can increase the chances of cancer
Environment: mutagens (causes mutations), carcinogens (chemical that causes cancer), radiation , UV light, nonionizing radiation, organic chemicals, pollutants
Viruses: Hepatitus B and C cause liver cancer. HPV causes cervical and penile cancer. AIDS causes kaposi sarcoma.
Diet: high fat diet and obese can cause breast and prostate. Low fiber causes colon. Processed meats increase stomach cancer. High alcohol causes liver.
list the seven warning signs of cancer
- Chang in bower/bladder habits
- sore throat that does not heal
- unusual bleeding or discharge.
- thickening in breast of else wear
- indigestion or difficulty swallowing
- Obvious change in wart or mole
- nagging cough
Describe the tests that may be used to diagnose cancer (11)
Self exam: ABCDE (asymmetry, border is irregular, color, larger than 6mm, elevated)
Digital Rectal Exam: finger in but
Colon cancer: camera in butt or fecal blood test
Blood test
Urinalysis
Mammography: Xray
MRI
Ultrasound
Biopsies: remove cells for examination
Tumor marker test: tests for antibodies from tumors.
Genetic test: test for mutations in proto-oncogenes
describe how surgery, radiation therapy, chemotherapy, and newer methods are used to treat cancer.
Surgery: removing tumor
Radiation: ionizing radiation cause chromosomal breakage and cell cycle disruption
Chemo: treats entire body. Hopes to kill cancer cells that escape
tumor. Kill cells by damaging their DNA and interfere with DNA synthesis.
Newer Methods:
-Immunotherapy (vaccines against cancer antigens, engineered immune cells, designed antibodies.)
-p53 gene therapy (causes cancer cells to produce p53 causes apoptosis)
-Antiangiogenetic drugs (decrease tumor blood supply causes them to shrink)
summarize how polygenic inheritance, pleiotropy, codominance, and incomplete dominance differ from simple one-trait crosses.
Polygenic - several alleles, the effects of the each dominant allele are additive.
Pleiotropy - single mutant gene affects two or more unrelated traits.
Codominance - alleles are equally expressed.
Incomplete dominance - phenotype is an intermediate.
explain why x-linked disorders are more common in males than females.
X linked disorders are more common in males because they only need one recessive allele to be effected by the disorder.
Compare and contrast the structure and function of DNA and RNA
DNA: Double helix structure, nucleotides made of phosphate and sugar (backbone), and nitrogen base (ACGT)
Replicates, stores information in genetic code, undergoes mutation to provide variability.
RNA: AUCG nucleotides, single stranded
Explain why DNA replication is semiconservative
Each new strand has an old and new strand. The new strand is copied from the old strand.
Summarize the major steps in DNA replication (3)
- DNA helicase unzips and unwinds, breaking bonds
- DNA polymerase adds new DNA nucleotides
- DNA synthesis occurs in opposite directions. One strand goes beginning to end, the other makes copies in segments.
Explain the role of mRNA, tRNA, and rRNA in a cell
mRNA: messenger. Temporary copy of a gene carried from DNA to ribosomes where protein is made.
rRNA: helps with reading RNA to make protein
tRNA: carries amino acid to ribosome.
Understand the structure and function of genetic code
genetic code is the sequence of bases in DNA and mRNA that code for amino acids. Its a three base sequence in mRNA (codon)
Describe the process of gene expression via transcription and translation
Transcription: DNA is template for the RNA molecule. RNA polymerase makes RNA.
-DNA unzips and new strand is made based on each strand. Introns must be removed and exons are brought together.
Translation: copy is used as instructions to make protein in ribosome.
Explain how gene expression may be regulated by a cell
Pretranscription control: prevents DNA from being transcribed by keeping them tightly coiled.
Transcriptional control: Transcription factors must be turned on in order to transcribe their gene
Posttranscriptional control: DNA can still be altered, splicing
Translational control: translation is prevented or inhibited
Posttranslational control: Includes protein being folded correctly and taken to correct destination.
recognize the importance of DNA sequencing to the study of biology
DNA sequencing is determining the order of nucleotides in DNA.
We can identify alleles, identify suspects through DNA, understand evolution, and make copies of DNA segments using polymerase chain reaction.
state the purpose of the polymerase chain reaction and DNA cloning
Make millions of copies of a specific segment of a certain gene.
Can be used for fingerprinting, test for viral infections, compare bodily substances, and identify bodies for forensics.
Cloning makes an identical copy of DNA, cells, or organism. DNA cloning produces many copies of a gene.
Understand the goals of genome editing.
To cure diseases by replacing the mutated gene.
Summarize some products that have been produced using biotechnology
-transgenic organisms - we put foreign genes into them
-Bacteria have been genetically modified to eat up oil
Plants can resist insects, herbicides, and both. They can also be engineered to have a longer shelf life.
-Animals have been modified to increase food value. Mouse models.
Distinguish between functional and comparative genomics and proteomics.
Functional is learning how our genes function
Comparative compares human genome to animal genome.
Proteomics: study of structure, function, and interaction of cellular proteins.
Explain the difference between in vivo and ex vivo gene therapy.
Ex vivo: cells are taken out of the body, modified, and placed back into the body.
in Vivo: Therapeutic DNA is injected into cells and virus carries corrective gene.
Distinguish between chemical and biological evolution
chemical: forms complex biomolecules. occurred before origin of life
Biological: forms complex organisms due to survival of the fittest
discuss how the first organic monomers, polymers, protocell, and living cell may have evolved.
Monomers: evolved from inorganic compounds
polymers: monomers joined
Protocell: polymers became enclosed in a membrane
living cells: protocells acquired the ability to self replicate
explain the relationship between adaptation, natural selection, and the process of biological evolution
Adaptations: characteristics/behaviors that allow an organism to survive
favorable traits are passed on to offspring allowing species to survive (natural selection)
discuss how the fossil record, biogeography, and anatomical and biochemical evidence all support the concept of biological evolution
Fossil Record: prokaryotes are the first sign of life followed by eukaryotes. Transitional fossils show relationships between organisms.
Biogeographical: Separates different plants and animals to different continents.
Anatomical: Homologous structures have similar structures but different functions. Show common ancestor. Analogous structure have same function but have different structure. Do not share ancestry,
Similar embryological development, all have tail and pouch.
Biochemical: all living organisms have same molecules (DNA, RNA, enzymes). Humans share genes with simple organisms.
describe the characteristics unique to all primates, including humans (9)
mobile limbs
grasping hands
flattened face
binocular vision for depth perception
three types of cones
large brain
reduced rate of reproduction
immature offspring.
compare the structure of chimpanzee and human skeletons and list the adaptations in humans that make upright walking possible
- Human spine attaches to center of skull which places head over the midline of our body
- longer spine puts center of gravity over our feet
- broad pelvis and hips prevent swaying when walking.
- longer femur causes it to angle inward
- femur is larger at bottom and tibia is larger at top to form knee.
- toes are nonerodable and arch allows us to walk.
describe the major events in the evolution of the hominins
Walking upright
distinguish among the different theories regarding Homo sapiens evolution
Replacement Model: homo types migrated to Europe and we originated from them.
explain why multiple races of humans have evolved on Earth
Darker skin protects against UV, light skin ensures VD production in the skin.
Identify the relationship between ecosystems and the biosphere
Biosphere: Parts of the Earth that contain living things
Ecosystems: a certain area of the biosphere where organisms interact with the environment.
Identify ways in which autotrophs and heterotrophs obtain nutrient
autotrophs produce their own energy
heterotroph consume food for energy
Distinguish between the movement of energy and the movement of chemicals in an ecosystem
Energy flow through trophic levels. Produced absorbs sun, consumers get that energy by eating
Nutrients cycle. producer makes nutrients, consumers eat nutrients, they die and nutrients are absorbed from producers.
recognize the differences between a food web and a food chain
Food webs: show feeding relationships of all organisms in the ecosystem.
Food chains: show single path of energy flow
explain energy flow among populations through food webs
explain why a diagram of the trophic levels in most ecosystems resembles a pyramid
only 10% of the energy of one trophic level is available to go to the next trophic level.
identify the steps of the water cycle, carbon cycle, nitrogen cycle, and phosphorus cycle
Water: Evaporation and transpiration causes clouds to form and then is rains.
Carbon: CO2 is in air, plants take it in, plants release it into the air
Nitrogen: must be fixed by converting it to ammonium. It is then taken up by pants and when they are consumed it is transferred back to nitrogen.
Phosphorus: weathered rock brings phosphate into soil. plants take it up, organisms eat them, die, and phosphorus is decomposed into the soil.
identify how human activity can alter each of the biogeochemical cycles
discuss the potential consequences of climate change
Burning of fossil fuels
Explain how exponential growth and carrying capacity relate to human population growth
Exponential mean population doubles or goes quick. Carrying capacity is the max population that the environment can support.
compare the characteristics of an MDC with those of an LDC, and give an example of each
MDC: North America and Europe. Population growth is modest
LDC: Asia and Africa. Population growth is dramatic.
Distinguish between renewable and nonrenewable resources and give an example of each
nonrenewable: will run out. Fossil fuels
renewable: can naturally replenish. Water
Explain how human activity is influencing the natural resources of land, water, food, minerals, and energy
Land: large populations cause beach erosion, loss of habitat and buffer zones. Deforestation effects biodiversity.
Water: agriculture uses up most of water. removing water from aquifers causes land to sink.
Food: Fertilizers harm environment.
Energy:
Minerals: surface mining washing toxic wastes into the ecosystem.
identify examples of biological magnification
Pesticides
Describe the factors that are contributing to the current biodiversity crisis
Mass extinctions causes by habitat loss, alien species (nonnative species decrease population of native species), pollution, overexploitation (humans take from the wild to decrease populations so much they cannot recover), and disease.
identify the direct and indirect values to society for conserving biodiversity
Direct: medicinal use, agricultural use, consumption use,
Indirect: Decomposers break down our waste, water cycle gives us fresh water, ecosystems prevent soil erosion, Biodiversity contributes to biogeochemical cycles, regulate climate,
discuss what changes are needed to convert todays society into one that is sustainable.
Renewable resources
multi use farming
mass transit
recycling and composting
preserving wetlands
