Topic gudie vocabulary

• Terms: 

  • Centromeres:  center of the chromosome where the sister chromatids are held together

  • Centrosomes: is an organelle located near the nucleus in the cytoplasm that divides and migrates to opposite poles of the cell during mitosis and is involved in the formation of the mitotic spindle, assembly of microtubules, and regulation of cell cycle progression.

  • Centrioles: involved in the development of spindle fibers in cell division.

  • spindle fibers:  fibers produced by centrioles and they attach to a chromosome

• What is the role of histone proteins

  • a protein that provides structural support for a chromosome. Each chromosome contains a long molecule of DNA, which must fit into the cell nucleus. To do that, the DNA wraps around complexes of histone proteins, giving the chromosome a more compact shape.

• Order of mitosis phases as well as the stages of interphase

  • Mitosis steps 

    • 1.       Prophase

      • a.       Centrioles and centrosomes separate at the opposite end of the cell

      • b.   DNA is in sister chromatid

      • c.       

2.       Metaphase

• a.       Spindle fibers attatch to the sister chromatids as they line up in the middle

• b.       DNA is in 2 sister chromatids?

• c.  

3.       Anaphase   

• a.       Sister chromatids separate and move towards the centrioles/centrsomes

• b.   DNA is in Chromatid

• c.     

4.       Telophase

• a.       The nuclear membrane reforms, spindle fibers break apart, and the nucleolus becomes visible

• b.   DNA is in the chromatid

• c.    

• Stages of Interphase

  • G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth).

• What happens during G1, S and G2 

  • G1—  the stage where the cell is preparing to divide.

  • S phase—- s the period of wholesale DNA synthesis during which the cell replicates its genetic content

  • G2– a period of rapid cell growth and protein synthesis during which the cell prepares itself for mitosis.

•  What happens during each Mitosis phase

  • Prophase (Mitosis)

    • (1st stage of Mitosis) Chromosomes become visible, centrosomes separate and migrate toward opposite poles, mitotic spindles and asters form.

  • Metaphase (Mitosis)

    • (2nd stage of Mitosis) Chromosomes line up across the center of the cell. Fully formed spindle attach to the sister chromatids from opposite poles.

  • Anaphase (Mitosis)

    • 3rd stage of Mitosis) Centromere splits in half; sister chromatids separate into individual chromosomes; spindle fibers pull chromosomes to opposite pole.

  • Telophase

    • (4th stage of Mitosis) A nuclear membrane forms around each set of chromosomes, and the chromosomes decondense.

  • Cytokinesis

    • The final stage of the cell cycle, in which the cell's cytoplasm divides, distributing the organelles into each of the two new identical daughter cells.

• Result of mitosis

  • 2 identical daughter cells 

•  When do normal cells become cancer cells

  •  uncontrolled cell growth

    •   Benign tumor: cells that are clustered together, and less harmful

    •      Malignant tumor: capable of metasis, invasive and dangerous

  •   Metastasis : cancer cells can break loose and go to other parts of the body 

  •        Binary fission: how most prokaryotes reproduce

Meiosis- 10 multiple choice questions

•     Terms

  •  Homologous chromosomes: Two chromosomes in a pair – normally one inherited from the mother and one from the father.

  • Sister chromatids: two identical chromatids

  • Autosomes:  one of the numbered chromosomes, as opposed to the sex chromosomes

  •  sex chromosomes: a chromosome involved with determining the sex of an organism, typically one of two kinds. (X or Y)

  •  Gametes: a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

  •  somatic cells Cells of a living organism that has sperms or eggs for reproduction

    •  Examples: tissue and organs

• Goal of meiosis

  •  to produce gametes or sex cells.

•  Chromosome number in human cells (diploid and haploid number)

  • 23 Chromosmes in a human haploid cells 

• Diploid vs. haploid

  • Diploid: two complete sets of chromosomes in an organism's cells Ex: blood cells, skin cells

  • Haploid single set of chromosomes in an organism's cells. Ex: sperm and egg cells

•  Know each of the phases of Meiosis and what occurs in them

  •    Draw a picture and explain each Phase of Meiosis I

  • 

  •   Prophase I:

    • Chromatids thicken, nuclar membrane breaks down,

    •   Each sister chromatid pairs with its corresponding homoeologous chromosomes (this makes a tetrad)

  • Metaphase I

    •    Homologous chromosomes line up in the middle

  • Anaphase 1

    • When spindle fibers pull the homoglous chromosomes apart making sister chromatid toward the centriole

  •   Telophase I/cytokansis

    •   2 daughter cells are formed these are haploid but genetic info is still replicated

• Draw a picture and explain each Phase of Meiosis II

  •  Prophase II

    • Nuclear membrane breaks down, centrioles move to opposite sides, spindle fibers assemble

  •  Metaphase II

    •  Sister chromatids line up in the middle of the cell

  • Anaphase II

    • When spindle fibers pull the homologous chromosomes apart (making sister chromatids) toward the centriole

  • Telophase II

    • Four identical hapolid daughter cell are made

      •  These cells are gametes (egg or sperm)

      •  The cells have half  the amount of original chromosomes

• Crossing over

  • the exchange of chromosmes segments between a homologous chromsoes during prophase 1

• Similarities and differences of mitosis and meiosis

  • Differences and similarities between mitosis and meiosis

    • Mitosis:

      •   1 division

      •  Creates two identical daughter cells

      • Chromosomes # stay the same in new cells

      • Makes more body cells

    • o   Meiosis:

      •  2 divisions

      • Creates 4 genetically different cells

      •  chromosome # cut in half in new cells

      •  Purpose is to produce cells for reproduction

    •  Both

      •  Starts with a single parent cell

      •   DNA is copied during interphase

      •   Cell division 

DNA, RNA and Proteins- 12 Multiple choice

•   What happens during DNA replication (DNA Helicase, DNA Polymerase, DNA Ligase jobs)

  • DNA helicase unzips the DNA strands unwind and the hydorgen bonds are broken by DNA Helicase

  •   DNA polymerse joins the nucleotides according to base pairing rules and “proofreads” for mistakes

  •  DNA licase connects the segments to complete the new DNA strand

• Where does DNA replication occur

  • during S phase of the cell cycle in the nucleus

• What is protein synthesis

  •  the process in which cells make proteins. It occurs in two stages: transcription and translation.

•   Be able to go from DNA-DNA Copy-mRNA-Amino Acids

• What happens during transcription (and where)

  • the process of copying a sequence of DNA to produce a complementing stand of RNA

  • Where does it take place: nucleus

•    What happens during translation (and where)

  • Converts or translates the mRNA message into a polypeptide chain

  • Where does it take place: cytoplasm in a ribosome

• mRNA vs tRNA vs rRNA (what are they and what are their functions)

  • mRNA: carries the coded message from DNA to the rest of the cell

  •    rRNA: makes up ribosomes

  •    tRNA: transfers AA to the ribosome

• Codon vs anticodon

  • Codon:  a group of three bases on an mRNA strand. Pairs with anticodon

  • Anticodon: carries the amino acid and will connect to coresponding codon

•    What is a nucleotide composed of

  • Sugar molecule

  • Phosphate group

  • nitrogenous base (ATGC)

• Types of mutations and how to solve a mutation problem

  • Mutations: changes in an organism’s DNA

•   What are mutations: Point mutations, and Frameshift mutations

  • What are the different types of Point mutations and give an example:

    • Silent Mutations: substitute of a nucleotide does not alter the amino acid sequence

    • Nonsense Mutation:  substitution of a nucleotide that causes a stop codon and will alter the protein being made

    • Missense Mutation: substitution of a nucleotide that causes a change in the amino acid sequence

  • What two things could cause a Frameshift mutation and give an example:

    • an insertion or a deletion of the nucleotide

Genetics and Heredity- 18 multiple choice

•     Dominant and recessive alleles (define)

  • Dominant: the alles that is expressed when 2 different alles are present (TT)

  • Recessive: the alles that is expressed when 2 specific alles are present. (tt)

• Homozygous and heterozygous (define)

  • Homozygous: two identical alles for a particular gene (TT or tt)

  • Heterozygous: two different alles for the same gene (Tt)

•  What is an alleles?

  • Alleles: different forms of a gene

•    Sex chromosomes and autosomes

•  Mendel’s law of segregation

•  Mendel’s law of independent assortment

  • Law of Independent Assortment

    • Alles can segregate indpedently during the fermentation of gametes

      • This accounts for many genetic variations observed in plants, animals, and other organisms

•  Mendel’s principle of dominance

  • Some alleles are dominant and others recessive

•  Phenotype and genotype (define and be able to do ratios for Punnett squares)

  • Genotype: an organisms genetic makeup

  • Phenotype: physical expression of a gene (what the eyes see)

• Monohybrid crosses- 

  • Regular dominance

  • Codominant: Alles contribute to the phenotype equally (no blending of colors) so we will see both alles equally dominant.

  •  incomplete dominance: Some alles are neither dominant or recessive. The heterozygous phenotype is halfway between the two homozygous phenotypes

  • Sex-linked: A gene located on a sex chromosme

• The Y is small and offers little genes

• The X has genes including colorblindness and hemophilla

• multiple allele: Many genes have more than two alles and therefore have multiple alles. These are represented by a letter with a superscript

•  Dihybrid cross

•   Polygenic trait definition and example

  • Traits that are controlled by two or more genes. In some cases, an epistatic gene can interfere with the expression of genes (SEE CHART FOR EXAMPLE)

• Punnett Square Review Sheet

• What is a karyotype and how to read one

  • Shows a complete dipoloid set of chromosomes grouped together in pairs, arranged in order of decreasing size

• Down Syndrome, Turners Syndrome and Klinefelter’s- what are the chromosomes/characteristics

  • Downs

    • When chromosomes fail to separate during meiosis, resulting in a third chromosome on the 21 pairings.  (3 copies of the 21st chromosome). 

    • Distinct facial features, intellectual disability, and developmental delays

  • Turners (X0)

    • A female with only one x chromsome. 

    • Still has female characteristics, but do not have working female reproductive organs 

  • Klinefelter’s (XXY)

    • A male with an extra chromosome

    • Still has male characteristics but are infertile 

• What is a pedigree, how to read one and make one 

  • A chart that shows the presence or absence of a trait according to the relationship within the family

    • Roman nurmals: represents the generations

    • Regular numbers: represent family members from same generation

    • Circles: female

    • Sqaures: male

    • Haf shaded shape: represents family members from same generation

    • Fully shaded shape: represents that the person expresses the trait

    • No shaded shape: represents that the person does not carry or express that trait.