In an observational test one has no control over the independent variable. In an experiment there is an independent and dependent variable, and one has control over the independent variable
Dependent variable: value depends on that of another, what is causing result, what you measured.
Independent variable: value does NOT depend on that of another
Ex: Effect flower color 0n attraction of bees. Ind: flower color, Dep: what result is
Properties of Life: order, evolutionary adaptation, response to the environment, growth and development, reproduction, energy processing, and regulation.
DNA allows for the properties of life to be maintained and passed from generation to generation
Eukaryotic chromosomes are made of chromatin. Chromatin is the complex of DNA and associated proteins that maintaining structure for gene activity and replication. Each single chromosome contains one very long DNA molecule that carries several hundred to a few thousand genes, the units that specify an organism’s inherited traits.
Cell Cycle: Interphase (G1, S, G2) and Mitotic (M) phase (mitosis and cytokinesis).
Cell spends most of their time in the G1 phase
DNA is replicated during the S phase
Cells divide in the Mitotic phase, as well as the seperation of sister chromosomes.
Mitosis: review diagrams in textbook, genetically identical daughter cells (development, growth, asexual reproduction)
G2: two chromosomes form from replication from a single centrosome (animal cells have two centrioles on each chromosome).
Prophase: chromatin coils; nucleoli disappear; chromosomes appear as sister chromatids joined at the centromere and along the arms by sister chromatid cohesion; mitotic spindle forms; centrosomes move away from each other.
Prometaphase: nuclear envelope fragments; chromosomes are more condensed; microtubules attach to kinetochore (specialized protein on centromere); non-kinetochore microtubules interact with those from opposite pole.
Metaphase: longest stage;