Task 1 - Data Analysis Task Flashcards
Cell Replication definition
most cells grow, perform the activities needed to survive, and divide to create new cells. These basic processes, known collectively as the cell cycle, are repeated throughout the life cycle of a cell.
Mitosis
Leads to the formation of two identical daughter cells that contribute to the growth and repair of the organism.
mitosis phases
interphase prophase metaphase anaphase telophase cytokinesis
Mitosis interphase
DNA replication complete. Chromosomes replicate to become double-stranded.
Mitosis prophase
Chromosomes condense, become visible and spindle apparatus forms.
Mitosis metaphase
Double-stranded chromosomes align along the equator of the cell.
Mitosis anaphase
Sister chromatids (single chromosomes) separate to opposite poles of cell.
Mitosis telophase
Nuclear membranes assemble around the two nuclei. Each nuclei with the same number of chromosomes as the parent cell. Diploid.
Mitosis cytokinesis
Division of cytoplasm into two cells.
Chromosome
A thread-like structure of nucleic acids (DNA or RNA) and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
Gametes
Sex cells
Centromere
The point where the two chromosomes join
Homologous chromosomes
Are the same length, have the centromere in the same position and carry genes for particular characteristics at the same location along their length.
Diploid number
Cell condition in which two of each type of chromosome are present. Number: 46
Haploid number
cell condition in which only one of each type of chromosome is present. Number: 23
Meiosis
Gives rise to gametes that transmit genetic material from one generation to the next during sexual reproduction.
Meiosis phases
Prophase I Metaphase I Anaphase I Telophase I and Cytokinesis Prophase II Metaphase II Anaphase II Telophase II and Cytokinesis
Meiosis early prophase
Chromosomes separate into homologous pairs.
Meiosis late prophase
- Nuclear membrane breaks down.
- Chromosomes split into chromatids.
- Crossing over occurs: genetic variation occurs.
Meiosis metaphase 1
- Chromosomes align in pairs in the middle of the cell.
- Random segregation
Meiosis anaphase I
-Chromosome pairs separate and each chromosome moves to the opposite end of the cell.
Meiosis telophase
- Two daughter cells form.
- Chromosome number is halved.
- Chromosome combinations in cells differ.
Meiosis cytokinesis 1
-Daughter cells are not identical to each other and have half the original number of chromosomes.
Meiosis metaphase II
-Chromosomes align at the equator.
Meiosis anaphase II
-Daughter chromosomes move apart, to opposite poles.
Meiosis cytokinesis II
-Four resulting daughter cells are not genetically identical to each other and have half the original chromosome number.
Nucleotide
Consists of three parts - a phosphate, a sugar and a nitrogenous base.
What are the four nitrogenous bases?
Adenine, Thymine, Guanine, Cytosine.
RNA?
Single-stranded molecule made of nucleotides, with a ribose sugar attached to each phosphate to form the backbone; on the other end it attaches to a base, either A, uracil (U), C or G.
Amino acid
Often referred to as the building blocks of proteins, are compounds that play many critical roles in your body. Is a chemical building block of polypeptides.
Polypeptides
Are chains of amino acids. Proteins are made up of one or more polypeptide molecules. Peptide bonds hold the amino acids together.
Protein
A large molecule made up of polypeptides chains, formed by sequences of amino acids linked together by peptide bonds and which contain other chemical elements
DNA
Consists of long chains of nucleotides wound into a double helix. The sequence of nucleotide bases determines the meaning of the message.
Messenger RNA (mRNA)
Messenger RNA (mRNA)? Is a copy of one side of an unzipped DNA double helix except the nucleotide Thymine is replaced with Uracil. Plays an important role in the production of proteins.
Transfer RNA (tRNA)
An RNA molecule that functions as an interpreter picking up specific amino acids and recognising the appropriate codons to attach to on the mRNA.
Gene
A segment of DNA on a chromosome that codes for a specific trait.
Locus (Pl. Loci)
A segment of DNA; the position of a gene on a chromosome.
Genome
The complete set of genetic material within a cell or that an organism has in each of its cells.
Alleles
Are different forms of the same gene.
Trait
A particular physical feature or characteristic of an organism.
Phenotype
The physical expression of that trait (physically observed characteristic). It is influenced by the environment: genes + environment = phenotype and is determined by the genotype.
Epigenetic
Chemical modifications of DNA that do not involve a change in the sequence of nucleotides. Usually environmental.
three types of RNA
Messenger RNA (mRNA), transfer RNA (tRNA), tibosomal RNA (rRNA)
Transcription
Transcription is the process of RNA synthesis, controlled by the interaction of promoters and enhancers. Several different types of RNA are produced, including messenger RNA (mRNA), which specifies the sequence of amino acids in the protein product, plus transfer RNA (tRNA) and ribosomal RNA (rRNA), which play a role in the translation process.
Transcription initiation
the DNA molecule unwinds and separates to form a small open complex. RNA polymerase binds to the promoter of the template strand.
Transcription - elongation
One strand of DNA, the template strand, acts as a template for RNA polymerase. As it “reads” this template one base at a time, the polymerase builds an RNA molecule out of complementary nucleotides, making a chain that grows from 5’ to 3’. The RNA transcript carries the same information as the non-template (coding) strand of DNA, but it contains the base uracil (U) instead of thymine (T).
Transcription - termination
The mRNA then moves out of the nucleus and into the cytoplasm ready for translation.
Translation
Translation is the process of translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis.
Translation -initiation
Initiation (“beginning”): in this stage, the ribosome gets together with the mRNA and the first tRNA so translation can begin.
Translation - elongation
Elongation (“middle”): in this stage, amino acids are brought to the ribosome by tRNAs and linked together to form a chain.
Translation - termination
Termination (“end”): in the last stage, the finished polypeptide is released to go and do its job in the cell.
Genotype
The set in the DNA responsible for a particular phenotypic trait.
Homozygous
2 alleles are the same for a particular characteristic (purebred) which is seen as: TT or tt.
Heterozygous
2 alleles are different for a particular characteristic (hybrid) which is seen as: Tt.
Dominant alleles
Overpower/mask recessive alleles. It is displayed with a capital letter as it is dominant (D).
Recessive alleles
Are hidden/asked by dominant alleles. It is displayed with a lowercase letter as it get dominated over (r).
Law of segregation
During gamete formation, the pair of alleles for a tree segregate and each gamete receives only one allele for the trait/gene - first law (segregation).
Law of independent assortment
When the inheritance of more than one trait/gene is studied, the pair of alleles for each trait separate independently of the other pairs of alleles - second law (independent assortment).
Autosomal recessive inheritance
A version of each characteristic/trait in each individual is inherited from both parents and therefore controlled b a pair of factors (called alleles).
The alleles pass from one generation to the next according to a set ratio
The alleles in an individual may be the same (pure-breed/homozygous individuals) or may differ (hybrid/heterozygous individuals). In hybrids, a trait that is expressed is known as the dominant allele and the hidden or masked is the recessive allele. For a recessive trait to be expressed, both alleles must be received.
Punnett squares
A representation of the possible genotypes of an offspring.
Incomplete dominance
A pattern of inheritance in which two alleles, inherited from the parents, are neither dominant nor recessive. The resulting offspring have a phenotype that is a blending of the parental traits.
Example; a snapdragon flower that is pink as a result of cross-pollination between a red flower and a white flower.
Codominance
When both alleles of a gene are dominant and the heterozygous phenotype has both traits equally expressed.
Example; a red bull and a white cow produce a roan calf.
Multiple alleles
The presence of more than two alleles for a genetic trait.
Blood types are an example of multiple alleles: A, B, O. the A and B alleles are codominant to each other and are both dominate over the O allele, making the O allele recessive
Pedigree (family trees)
Squares are used to represent males, circles are used to represent females.
A line between (horizontal) a male and female indicates mating (marriage), a vertical line from the parents indicates offsprings and shading are used to indicate the individuals showing the trait.
Autosomal dominant
An affected individual ALWAYS has one affected parent and two affected parents can have an unaffected child.
Autosomal recessive
An affected individual may have unaffected parents and two affected parents only can have affected children.
Sex-linked inhertiance
The two possible sex chromosomes: X and Y. Females have a homologous pair of X chromosomes and males have one X chromosome and one Y chromosome, therefore, the father determines the gender of the embryo
The sex chromosome is found on the 23rd chromosome.
Hence sex-linked conditions commonly occur on the X chromosome.- males inheritance can skip a generation (grandfather to grandson for example). All sons of an affected female are also affected.
A carrier has the allele that causes a condition but does not express it.
WHY IS POLYPEPTIDE SYNTHESIS IMPORTANT?
In order to make proteins which are super important for cell and organism structure and function
Polypeptide synthesis steps
DNA replication –> RNA (transcription) —> proteins (translation).
What is the difference between co-dominance and incomplete dominance?
Co-dominance is when both alleles in a gene pair are fully expressed (e.g. a spotted brown and white cow) while incomplete dominance is when a third phenotype is created which is a blended version of both alleles (e.g. a pink rose from breeding a red and white one together)
What are pedigree charts?
Charts showing family relationships and phenotypes. It helps to trace phenotypes through generations.
What are punnet squares?
charts used to theorise the possible gene combinations in a cross between 2 organisms
polygenic inheritance
occurs when multiple genes determine the phenotype of a trait
complete dominance
a relationship in which one allele is completely dominant over another
Fertilisation
Fusion of haploid male and female gametes.
