Unit 3 exam

biology

know the endomembrane system function and be able to tie it to the central dogma of molecular Biology

The endomembrane system is responsible for the synthesis, modification, packaging, and transport of proteins and lipids within a cell, facilitating processes like secretion and membrane formation. This system is integral to the central dogma of molecular biology, as it translates genetic information from DNA to functional proteins.

know the life cycle of cells: the periods(prokaryotic) and phases (eukaryotic) of the cells cycle.

The life cycle of cells refers to the series of stages that cells go through from one division to the next. In prokaryotic cells, the cycle typically includes growth and binary fission, while eukaryotic cells undergo interphase (including G1, S, and G2 phases) followed by mitosis and cytokinesis.

Prokaryotic Cell cycle:

The series of stages including growth and binary fission that a prokaryotic cell undergoes from one division to the next.

B period:

This period is characterized by growth and the preparation of the cell for DNA replication. During this period, the cell increases in size and synthesizes proteins and organelles necessary for DNA synthesis.

C period;

The period in the prokaryotic cell cycle characterized by DNA replication, where the cell's genetic material is duplicated in preparation for division.

D period:

The final stage of the prokaryotic cell cycle that involves cytokinesis, where the cell divides into two daughter cells, completing the cell division process.

Eukaryotic Cell cycle(Phases): Interphase:

The phase of the eukaryotic cell cycle that includes G1 (cell growth), S (DNA synthesis), and G2 (final preparations for mitosis), allowing the cell to grow and replicate its DNA before mitosis.

G1:

The first phase of interphase in the eukaryotic cell cycle, during which the cell grows, produces RNA, and synthesizes proteins necessary for DNA replication.

S phase:

The phase of interphase in the eukaryotic cell cycle where DNA synthesis occurs, resulting in the replication of the cell's genetic material.

G2:

The second phase of interphase in the eukaryotic cell cycle, during which the cell continues to grow and prepares for mitosis by producing necessary proteins and organelles.

M phase:

The phase of the eukaryotic cell cycle where cell division occurs, encompassing both mitosis and cytokinesis, resulting in the formation of two daughter cells.

Mitosis:

The process of cell division that occurs in the M phase of the cell cycle, where a single cell divides to produce two identical daughter cells, maintaining the same chromosome number.

Cytokinesis:

The final stage of cell division, following mitosis, where the cytoplasm divides and separates the two daughter cells.

Know the phases within the M phase:

Prophase, Metaphase, Anaphase, Telophase

Prophase:

The first stage of mitosis, during which chromatin condenses into visible chromosomes, the nuclear envelope breaks down, and spindle fibers begin to form.

prometaphase:

The stage of mitosis that follows prophase, where the nuclear envelope is completely dissolved, chromosomes become more condensed, and spindle fibers attach to kinetochores.

Metaphase:

Anaphase:

The stage of mitosis where chromosomes align at the cell's equatorial plane, and the spindle fibers attach to the centromeres of the chromosomes, preparing them for separation.

Telophase:

The final stage of mitosis, during which the chromosomes begin to decondense, the nuclear envelope re-forms around each set of chromosomes, and the cell prepares to divide into two daughter cells.

Cytokinesis:

The process that occurs after telophase in mitosis, where the cytoplasm of a parental cell divides into two daughter cells, each with its own nucleus and organelles.

Know the steps in Meiosis and what is different between mitosis and meiosis

Meiosis comprises two rounds of division (meiosis I and II), resulting in four non-identical daughter cells, each with half the number of chromosomes of the original cell. Unlike mitosis, meiosis includes crossing over and homologous chromosome separation, increasing genetic diversity.

Be familiar with prokaryotic organisms ability to increase genetic diversity even though binary fission is asexual.

Prokaryotic organisms can increase genetic diversity through mechanisms such as horizontal gene transfer, transformation, transduction, and conjugation, allowing them to share genetic material despite reproducing asexually.

Know the difference between transformation, transduction and conjugation.

Transformation involves the uptake of naked DNA from the environment, transduction is the transfer of DNA via bacteriophages, and conjugation requires direct cell-to-cell contact for the transfer of plasmid DNA.

Know the structure of DNA and RNA (as well as the differences between the two biomolecules.)

DNA is a double-stranded helix composed of nucleotides featuring deoxyribose sugar, while RNA is typically single-stranded and contains ribose sugar. The base composition also differs; DNA uses thymine, whereas RNA contains uracil instead.

Be familiar with the process of DNA replication and the terminology related. to this process.

DNA replication is the process by which a DNA molecule makes a copy of itself, involving key steps such as initiation, elongation, and termination. Important terms include leading strand, lagging strand, helicase, and DNA polymerase.

Know classification of nucleotides ( the single ring pyridine vs the double ring purines) and which nucleotides are used in which nucleic acid.

Nucleotides are classified into pyrimidines, which have a single ring structure (cytosine, thymine, uracil), and purines, which have a double ring structure (adenine, guanine). In DNA, the nucleotides include adenine, thymine, cytosine, and guanine, while RNA contains adenine, uracil, cytosine, and guanine.

Know what the term “genome” means

The genome is the complete set of genetic material contained within an organism's cells, including all of its genes and non-coding sequences.

Know the terminology associated with chromosomes: Unreplicated vs replicated, homologous chromosomes, non-homologous chromosomes, sister chromatids, chromatin, nucleosome, centromere, mitotic spindle, kinetochore.

The terminology associated with chromosomes refers to the structures and concepts that define their organization and function during cell division. This includes terms like unreplicated (single chromatid) and replicated (two sister chromatids), homologous chromosomes (pairs from each parent), non-homologous chromosomes (not matching pairs), chromatin (packaged DNA), nucleosome (DNA wrapped around histones), centromere (constriction point), mitotic spindle (microtubule structure for separation), and kinetochore (protein complex for chromosome movement).

Know the three tenets of gene theory and the central dogma of biology.

The three tenets of gene theory state that genes are the units of heredity, they are located on chromosomes, and that they dictate the traits of an organism. The central dogma of biology describes the flow of genetic information from DNA to RNA through transcription, and from RNA to protein through translation.

what are the steps that are involved with gene expression

The steps involved in gene expression include transcription, where DNA is converted into RNA, and translation, where RNA is used to synthesize proteins. These processes work together to express the genetic information carried by genes.

be familiar with the sequence of protein structure- from primary protein through quaternary protein.

The sequence of protein structure includes four levels: primary (amino acid sequence), secondary (alpha helices and beta sheets), tertiary (three-dimensional folding), and quaternary (assembly of multiple polypeptide chains). This hierarchy is crucial for the protein's function and stability.

be familiar with some of the mechanisms of controlling gene expression.

Mechanisms of controlling gene expression include transcription factors that bind to DNA, epigenetic modifications such as DNA methylation and histone modification, and regulatory RNAs like microRNAs that inhibit translation. These mechanisms help fine-tune gene activity in response to environmental signals.

know what a mutation is and the different forms (base substitutions, insertions/deletions, chromosomal aberrations) of mutations and possible effects.

A mutation is a change in the DNA sequence that can occur in various forms, including base substitutions, insertions or deletions, and chromosomal aberrations. These mutations can lead to alterations in protein function, potentially resulting in genetic disorders or varying phenotypic effects.