BIOLOGY FINAL EXAM FLASHCARDS
Chromosome:
genetic info bundled into packages of DNA
Chromatin:
DNA tightly to histone
Cell Cycle:
a cell grows, copies its DNA, prepares for division, and then divides.
Histone:
proteins
Cytokinesis:
division of the cytoplasm
Prophase:
genetic material condenses and duplicated chromosomes become visible
Chromatids:
condensed chromosomes that appear as thick strands
Centromere:
point at which sister chromatids are attached
Metaphase:
centromeres of the chromosomes line up at across the center of the cell
Centrioles:
structure that the midpoint of a chromosome
Anaphase:
chromosomes separate and move along the spindle fibers to the ends of the cell
Telophase:
chromosomes spread out in a tangle of chromatin
Alleles:
different forms of a single gene
Spindle Fibers:
protein structure that divides the genetic material in a cell
Meiosis:
a type of cell division in sexually reproducing organisms that reduces the number of chromosomes in gametes
Mitosis:
a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
Ploidy:
Whether its Haploid or diploid
Haploid:
½ the amount of chromosomes present (½ set) n
Diploid:
double the amount of chromosomes present (1 full set of chromosomes) 2n
Tetrads:
After parent haploids mate, they produce diploids.
Homologous pair:
two chromosomes in a pair – normally one inherited from the mother and one from the father. For example, the two copies of Chromosome 1 in a cell would be referred to as homologous chromosomes.
Zygote:
A zygote is a eukaryotic cell formed by a fertilization event between two gametes
Chiasma:
Chiasma: Point of crossing over
INdependent assortment:
adds genetic variation
Growth factor:
stimulate growth and division of cells
Apoptosis:
programmed cell death
Cancer:
body cells that lose the ability to control growth
Tumor:
mass of cancer cells
Embryo:
developmental stage from which an adult organism is produced
Differentiation:
cells becoming specialized
Totipotent:
able to develop into any type of cell
Stem cells:
unspecialized cells form which differentiated cells develop
Genetics:
scientific study of biological inheritance
Fertilization:
male and female reproductive cells join to produce a new cell during sexual reproduction
Hybrid:
the offspring of crosses between parents with contrasting characteristics
Trait:
a specific characteristic
Hybrid:
the offspring of crosses between parents with contrasting characteristics
Segregation:
how pairs of genes are separated into reproductive cells
Principle of Dominance:
some alleles are dominant and some are recessive
Gametes:
reproductive cells
Probability:
likelihood of a particular event
Homozygous:
organisms that have identical alleles for a particular gene
Heterozygous:
organisms that have two different alleles for the same gene
Genotype:
genetic makeup
Karyotype:
a photograph of all of an organism’s chromosomes
Phenotype:
physical trait
G Banding
G banding or Giemsa banding is a technique used in cytogenetics to produce a visible karyotype by staining condensed chromosomes.
Describe the process and importance of mitosis:
- Prophase: Cell builds spindle to help to separate duplicated chromosomes (Plant cells lack centrioles (where spindle fibers come from))
- Metaphase
- Anaphase: Ends when movement stops chromosomes are separated into 2 groups
- Telophase: Nuclear envelope reforms, Nucleus becomes visible
- Cytokinesis: 2 nuclei are formed,
Regulatory Proteins and Cell division
Controls on cell division Divide until they come into contact with one another
Injury causes cells to be stimulated and divide rapidly
Regulatory proteins:
respond to events inside the cells, Act as checkpoints
3.8 Describe the process and importance of meiosis.
ensures that all organisms produced via sexual reproduction contain the correct number of chromosomes.
Explain symptoms, treatment, diagnosis, and current research for a specific type of cancer:
symptoms: constant headaches, vision trouble, issues with speaking, seizures, weakness, and mood changes
Diagnosis:
Computed tomography (CT or CAT) scan
This takes photos of the brain using x rays from different angles. They are then examined and can be used to determine the size of the tumor and if the skull/ bone is fractured.
1.Magnetic resonance imaging (MRI).
In contrast to an CT scan MRI’s use magnetic fields that cause the atoms in your body to align in the same direction to determine the size and location of the tumor.
Biomarker testing of the tumor.
Biomarker testing takes a sample of the tumor and analyzes it to identify unique genes, proteins and other
Biopsy
A biopsy is the only test that can diagnose the type and grade of astrocytoma with certainty. During the Biopsy a neurosurgeon will take a piece of the tumor and give it to a pathologist to analyze it.
Neurological exam
A healthcare worker will ask about your symptoms (the ones listed above)
Current research:
Immunotherapy: a type of therapy where the immune system is stimulated to attack the tumor. Astrocytoma weakens the immune system so research is going on to continue to find ways for the immune system to fight back against the tumor. This doesn’t work for all types of cancer. It can be in the form of a drug that is taken along with chemotherapy or radiation therapy, an anti tumor vaccine, or through intravenous infusion of genetically modified immune cells.
Bevacizumab (Avastin): a type of drug used in targeted therapy. Targeted therapy targets the proteins that help cancer grow. First approved for treatment of colon cancer in 2004, but it hasn’t been approved for too many types of cancer yet. It was approved for Astrocytoma in 2009. It was also used for breast cancer but was removed in 2011 for that use by the FDA because it was shown to have not been safe for that use. This drug cuts off the protein that gets the cancer, the blood and oxygen cells that it needs to keep growing. It is still being tested to become more effective for more cancers.
3.9 Define Mendel’s laws.
law of dominance: some alleles are dominant and some are recessive
law of segregation:how pairs of genes are separated into reproductive cells
law of independent assortment: adds genetic variation
Define and explain how to karyotype:
G Banding: G banding or Giemsa banding is a technique used in cytogenetics to produce a visible karyotype by staining condensed chromosomes.
4.1 Describe the importance of Charles Darwin and his work
survival of the fittest, evolution, diversity
4.2 three main driving forces of evolution.
Mutations-
Genetic Drift-
Natural Selecton
Genetic Drift-
isolated populations evolve differently
Bottleneck effect- change in allele frequencies after a dramatic reduction in population size
Founder effect- when a small part of a population colonizes a new area, it is only their genes that are passed on
Mutations-
change in DNA sequence of of a cell
Fundamental genetic shifts- abrupt change in a genetically determined trait due to mutation, a random mutation
Frameshift- deletion or addition of a DNA sequence that changes the DNA
Point- can point to where the DNA changed
Genetic Drift- isolated populations evolve differently
Bottleneck effect- change in allele frequencies after a dramatic reduction in population size
Founder effect- when a small part of a population colonizes a new area, it is only their genes that are passed on
Natural Selection-organisms better adapted to their environment will survive better
Charles Darwin’s finche
Natural Selection-
organisms better adapted to their environment will survive better
stabilizing
directional
disruptive
ex: Charles Darwin’s finches
4.3 Explain the five basic concepts of natural selection and how they impact evolution.
VISTA
Variation and Inheritance
Members of any given species are seldom exactly the same, either inside or outside. Organisms can vary in size, coloration, ability to fight off diseases, and countless other traits. Such variation is often the result of random mutations, or “copying errors,” that arise when cells divide as new organisms develop.
When organisms reproduce, they pass on their DNA–the set of instructions encoded in living cells for building bodies–to their offspring. And since many traits are encoded in DNA, offspring often inherit the variations of their parents. Tall people, for example, tend to have tall children.
Selection: Survival and Reproduction
Environments cannot support unlimited populations. Because resources are limited, more organisms are born than can survive: some individuals will be more successful at finding food, mating or avoiding predators and will have a better chance to thrive, reproduce, and pass on, their DNA. Small variations can influence whether or not an individual lives and reproduces. Differences in color, for instance, aid some individuals in camouflaging themselves from predators. Sharper eyes and claws help an eagle catch its dinner. And brighter coloration improves a male peacock’s chances of attracting a mate.
Directional Selection:
When individuals at one end of the curve with extreme traits have higher fitness than anywhere else on the curve.
Over time, the population changes to show this traits as they gradually shift in that direction
Time and Adaptation:
In generation after generation, advantageous traits help some individuals survive and reproduce. And these traits are passed on to greater and greater numbers of offspring. After just a few generations or after thousands, depending on the circumstances, such traits become common in the population. The result is a population that is better suited–better adapted–to some aspect of the environment than it was before. Legs once used for walking are modified for use as wings or flippers. Scales used for protection change colors to serve as camouflage.
4.4 Identify the impacts of the three types of selection on a population’s phenotype.
Stabilizing Selection:
Directional Selection:
Disruptive Selection:
Stabilizing Selection:
When individuals with non extreme traits in the center of the curve have higher fitness than anywhere else on the curve.
Over time, individuals stay the same and more of the population comes to show those traits