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100 terms

Unit 3 Test Study Guide

Includes Key Terms, Review Questions, Conclusion Questions, Important Introduction Info, and Powerpoint info
a condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume
Blood plasma
the pale yellow fluid portion of the whole blood that consists of water and its dissolved constituents including sugars, lipids, metabolic waste products, amino acids, hormones, and vitamins
Red Blood cells; contain hemoglobin and carry oxygen and carbon dioxide; responsible for the red color of blood
the percent of the volume of whole blood that is composed of red blood cells as determined by separation of red blood cells from the plasma usually by centrifuation
tells the hematocrit
White blood cells; any blood cells that are colorless, lack hemoglobin, contain a nucleus, and include the lymphocytes, monocytes, neutrophilis, eosinophils and basophils
Sickle Cell Disease
individuals who are homozygous for the gene controlling hemoglobin S. The disease is characterized by the destruction of red blood cells and by episodic blocking of blood vessels by adherence of sickle cells to the vascular endothelium.
Platelets; a minute colorless anucleate disklike body of mammalian blood that assists in blood clotting by adhering to other platelets and to damaged epithelium
Amino Acid
An organic monomer which serves as a building block of proteins
A triplet of nucleotide bases in transfer RNA that identifies the amino acid carried and binds to a complementary codon in messenger RNA during protein synthesis at a ribosome
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code
affinity for water
aversion to water; tend to coalesce and form droplets in water
Messenger RNA (mRNA)
A type of RNA, synthesized from DNA and attached to ribosomes in the cytoplasm; it specifies the primary structure of a protein.
A rare change in the DNA of a gene, ultimately creating genetic diversity; can be deletion or subsitituion
the building block of nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group
A three dimensional polymer made of monomers of amino acids
Protein Synthesis
the creation of a protein from a DNA template
Ribonucleic Acid (RNA)
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G) and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses
A cell organelle that functions as the site of protein synthesis in the cytoplasm; consists of ribosomal RNA and protein molecules and is formed by combining two subunits
the synthesis of RNA on a DNA template
Transfer RNA (tRNA)
A RNA molecule that functions as an interpreter between nucleic acid and protein language by picking up specific amino acids and recognizing the appropriate codons in the mRNA
the synthesis of a polypeptide (most likely a protein) using the genetic info encoded in an mRNA molecule. There is a change of language from nucleotides to amino acids
Any of the alternative forms of a gene that may occur at a given locus
A chromosome that is not directly involved in determining sex, as opposed to a sex chromosome
Any of the usually linear bodies in the cell nucleus that contain the genetic material
Dominant trait
A genetic trait is considered dominant if it is expressed in a person who has only one copy of the gene associated with the trait
a discrete unit of hereditary info; usually found on the DNA
Genetic Material
molecules responsible for heredity and variation of organisms
All or part of the genetic constitution of an individual or group
the transmission of traits from ancestor to descendant
Homologous Chromosomes
chromosomes having the same or allelic genes with genetic loci usually arranged in the same order
a display of the chromosome pairs of a cell arranged by size and shape
The cellular process that results in the number of chromosomes in gamete-producing cells being reduced to one half and that involves a reduction division in which one of each pair of homologous chromosomes passes to each daughter cell
a process that takes place in the nucleus of a dividing cell, involves a series of steps, and results in the formation of two new nuclei each having the same number of chromosomes as the parent nucleus
a diagram of a family tree showing the occurrence of inheritable characteristics in parents and offspring over multiple generations
the observable properties of an organism that are produced by the interaction of the genotype and the enviroment
Recessive trait
a condition that appears only in individuals who have received two copies of a mutant gene, one copy from each parent
sex chromosome
one of the pair chromosomes responsible for determining the sex of an individual
Punnett Square
a simple graphical way of discovering all of the potential combinations of genotypes of an offspring, given the parents' genotypes
Sickle Cell characteristic
defective hemoglobin causes the red blood cells to become stiff instead of flexible and form a sickle or a crescent
Why does the sickling of red blood cells cause healthy problems?
Sickle-shaped red blood cells can get stuck in small blood vessels, blocking them. This keeps red blood cells and the oxygen they carry from getting to all parts of the body.
What is sickle cell anemia?
sickle cell anemia is one type of anemia. Anemia is a condition in which your blood has a lower than normal number of red blood cells. This condition also can occur if your red blood cells don't contain enough hemoglobin
How is anemia diagnosed?
to diagnose anemia, your doctor will likely ask you about your medical history, perform a physical exam, order blood tests, specifically on hematocrit using centrifugtion.
Symptoms of Sickle Cell
painful events, splenic sequestration, acute chest syndrome (which involves chest pain), aplastic crisis
DNA code
Adenine - Thymine
Guanine - Cytosine
What is the connection between genes and proteins?
Genes are made up of strains of proteins called amino acids
How are proteins produced in a cell?
First, a cell must make a chain of amino acids; then the chain of amino acids make a copy of its DNA in the nucleus, which is mRNA. The mRNA goes out of the nucleus, which the DNA cannot, and in the cytoplasm with connection to a ribosome, makes tRNA eventually the ribosome codes this RNA to amino acids, which make a protein
How does the sequence of nucleotides in DNA determine the sequence of amino acids in a protein?
DNA undergoes a transcription and then translation in order to determine the amino acid
What is a mutation?
a mutation is a permanent change in the DNA sequence of a gene
What determines the shape of a protein?
the sequence of amino acids
Is the shape of a protein affected by its surrounding environment?
Yes, if the protein is under the effect of denaturing agents, its shape will be changed. Therefore, it loses its function.
How does a change in the DNA code affect the shape of a protein?
If the DNA is changed, when it's transcribed into RNA, the pattern will be different or wrong. This will cause the wrong amino acids to be created, which will change the shape of a protein. That protein will not be able to function in the same way
Can changing just one nucleotide in a gene change the shape of a protein?
Yes, changing one nucleotide will change the codon and therefore change the amino acid in the chain which changes the protein that is made
How is DNA passed to new cells during cell division?
Once DNA has been replicated it; the two sister chromatids are pulled to opposite sides of the cell thus creating two separate nuclei
What is a chromosome?
A threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic info in the form of genes.
How are traits passed through the generations?
The parents give the next generation 23 chromosomes each. These chromosomes contain DNA, which has genes that translate into traits. When these 23 chromosomes are passed down, the traits are passed down as well.
How are pedigrees used to track diseases?
Pedigrees are used to be set up the generations, and show who is affected and who is not affected. These pedigrees show the outcome of when two people mate, and the prediction if they're children are affected or not. Though you can track diseases, one pedigree can track only one disease
Why does sickle cell disease run in families, yet is not present in every generation?
Sickle cell is a recessive disease, and for a person to have sickle cell, the person has to inherit the disease on both chromosomes that have been inherited. Sickle cell can show in generations, but other generations can carry the trait but do not have the disease. These are called carriers.
Function of collagen
help tissues withstand stretching
Function of amylase
enzyme that helps digest carbohydrates
Function of hemoglobin
located in the red blood cells, carries oxygen
Function of insulin
regulates blood sugar levels
Function of Platelets
help the blood clotting process; stick to the injured blood vessel to allow blood clotting
Function of red blood cells
helps carry oxygen from the lungs to the rest of the body; returns carbon dioxide from the body to the lungs so it can be exhaled
Function of white blood cells
protect body from infection; regulates the function of other immune cells
Function of Plasma
to transport blood cells throughout body along with nutrients, waste products, antibodies, platelets, and hormones
How to determine hematocrit
(Red blood cell level/total blood level) x 100
Low Hematocrit for Females (Anna)
less than 35%
Normal Hemtocrit for Females
35 - 46
Why would having a sickle cell anemia crisis result in a reduced red blood cell count, an elevated white blood cell count, and a reduced hematocrit?
A reduced red blood cell count results because sickle cell contains an ill normal hemoglobin. These cells do not form correctly, and stick to the arteries and veins. The red blood cells that are created have short life cycles, and die quicker than bone marrow can produce them. The white blood cells actually start attacking the sickle cell infected cells, leading to an elevated white blood cell count.
Describe how the DNA code is translated into mRNA
a. The double-stranded DNA unwinds and RNA polymerase binds to one of the strands
b. The RNA polymerase reads the gene and makes a copy in the form of a single strand of RNA
c. Segments not needed to make a protein are cut out and the remaining is spliced together
d. The mRNA is shipped out of the nucleus to a ribosome.
Why do you think scientists call a subsitutions a "point mutation"?
Substitution is most likely called 'point mutation' because it only changes the code at one 'point' of the whole DNA/mRNA strand.
Why do you think scientists call a deletion a "frameshift mutation"?
'Frameshift mutation' gets its name from completely shifting the whole strand over one 'frame'. They still code every three, but it's a different three from the normal strand.
What mutates in order to have sickle cell?
Glutamic acid changes to valine
Steps from DNA to protein
o The double-stranded DNA unwinds and RNA polymerase binds to one of the strands
o The RNA polymerase reads the gene and makes a copy in the form of a single strand of RNA
o Segments not needed to make a protein are cut out and the remaining is spliced together
o The mRNA is shipped out of the nucleus to a ribosome.
o Ribosome translate the mRNA into amino acids
o Match nucleic acids with their matching amino acids to build a protein
o Chain of amino acids grow until message stops
o Ribosome releases the protein
What kind of protein is the sickle cell?
beta-globin protein
How do hydrophilic amino acids react in water and oil?
amino acid chains are charged or polar, attract water to places on their surface; when put in oil they will be more attracted to each other than to the surrounding molecules
How do hydrophobic amino acids react in water and oil?
mino acid side chains are electrically neutral and non-polar in relation to water and do not lose or gain electrons and do not have shifted; dissolve in oil
Glutamic Acid
Hydrophilic and negative charge
Hydrophobic and neutral charge
Describe how a single amino acid substitution causes hemoglobin molecules to stick together. Use what you know about the structure of Hb and HbS, the properties of glutamic acid and valine, and how hydrophobicity causes molecules to behave in water.
With the addition of a valine, hydrophobic regions appear on the surface of HbS. These hydrophobic molecules gather together in watery solution. Blood is a watery solution, and the HbS molecules would stick together on their hydrophobic regions.
What type of mutation is responsible for sickle cell disease and Tay Sachs disease?
Substitution is responsible for the two diseases. In both sickle cell disease and Tay Sachs disease, a base is substituted by a different base, causing the amino acid to have a different code, leading to the mutated protein with a wrong amino acid.
What is the property of alanine (the amino acid that makes up this polymer chain) that helps explain its reaction to water and oil?
Alanine is a hydrophobic molecule, so in water it will gather with the other molecules like itself, and in oil the atoms will dissolve. Hydrophobic and hydrophilic molecules have different reactions to water and oil, so being a hydrophobic atom that is why is behaves as so.
Explain why the replacement of the glutamic acid by valine changes the way that molecules of b-globin interact with each other.
The change makes two parts of the surface of the hemoglobin hydrophobic. This makes it easy for hemoglobin molecules to stick to each other. In regular blood, the glutamic acid makes the molecule hydrophilic and allows it to operate normally.
Explain why the change in the way that molecules of -globin interact with each other lead to the sickling of the red blood cells in sickle cell anemia.
The sickle blood cells are hydrophobic, and have a different shape than normal blood cells. This shape along with the hydrophobic properties allows the molecules to stick to each other. This sticking can lead to blood clots and more problems in the body.
How is hemophilia passed?
on the X chromosome, and it is a recessive disease
How is Best disease passed?
on Chromosome 11; it is a dominant disease
Steps of Mitosis
The DNA unwinds and form into chromosomes.
The chromosomes line up in the middle.
The chromosomes get pulled apart into sister chromatids.
A nucleus is form around the chromosomes as the cell pulls apart into two daughter cells.
Steps of Meiosis
DNA replicates then condenses into chromosomes; chromosomes pair up with their matching chromosome called homologous chromosomes; these line up at the center of the cell and the spindle fibers attach to each of the homologous chromosomes; then they are pulled to the opposite poles of the cell and split into two cells. These cells one homologous chromosome, line the chromosome in the middle, the fibers attach, and pull them apart; this leaves 4 cells each containing a single chromosome set. Males keep all four. Females only keep one
Purpose of Mitosis
The purpose of mitosis is to create more cells. If the cells did not undergo mitosis, there would be no more new cells to replace the old or damaged ones. Eventually our bodies could not even work because there are not enough cells
Why is it necessary for DNA to replicate in the first step in mitosis?
It is important for the DNA to replicate in the first step, so that each new cell can have a copy of the DNA. If it copied in another step, the cell may have an unequal number of chromatids, or not have both copies, from the mother and father, in the cell.
Why is it important that the end result of the process of meiosis is sex cells that contain half the amount of DNA?
It is important that they only have one half so that when the male and female donate one cell to the child, that together there are 23 pairs of chromosomes instead of 43 pairs.
Explain how DNA, chromosomes, and genes are related.
DNA contains the instructions, genes, to make proteins that tell what genetic traits the person will have. The DNA along with the proteins make up the chromosomes. The chromosomes are then passed on to the offspring, and with the DNA inside the chromosomes and translation of the genes, its traits are decided.
Explain why more males are afflicted with hemophilia than females.
Hemophilia is located on the X chromosome, and is a recessive disease. Males only have one X chromosome, while females have two. Males are more likely to have this disease because if the disease is given to them they don't have another X chromosome to cancel out the disease. Whereas females have two X chromosomes, so they can get the disease from one parent, but get the normal trait, which is dominant to cancel out the hemophilia disease.
Pedigree - Circle
Pedigree - Square
Pedigree - Filled Shape
Has the disease
Pedigree - White Shape
Pedigree - Half filled Shape