Lots of bio

DNA

Deoxyribonucleic acid that stores genetic information and codes for proteins.

Genome

All of the DNA in an organism, consisting of approximately 3 billion base pairs.

Nucleotide

The monomer of DNA, consisting of a 5-carbon sugar (deoxyribose), phosphate, and nitrogen base.

Complementary Strands

In DNA, adenine pairs with thymine and cytosine pairs with guanine.

Hydrogen Bonds

Weak bonds that hold together the nitrogen bases in DNA strands.

Covalent Bonds

Strong bonds holding the sides of the DNA ladder (sugar and phosphate) together.

Chromatin

Loose and unwound DNA, easily read and used for transcription.

Chromosomes

Tightly wound and compacted DNA, easily transported during cell division.

Semiconservative Replication

DNA replication process where each new DNA molecule consists of one original and one new strand.

Initiation (of DNA Replication)

The first step where helicase unwinds and unzips the DNA.

Elongation (of DNA Replication)

The step where DNA polymerase adds complementary nucleotides to the exposed strands.

Termination (of DNA Replication)

The final step where DNA is checked for errors and Okazaki fragments are joined.

Central Dogma

The flow of genetic information from DNA to RNA to Protein.

Transcription

The process of synthesizing RNA from a DNA template.

Translation

The process of synthesizing proteins using mRNA as a template.

Mutation

A change in the DNA sequence that can be positive, negative, or neutral.

Frameshift Mutation

Mutation caused by insertion or deletion of a nucleotide, shifting the reading frame.

PCR (Polymerase Chain Reaction)

A laboratory technique used to make multiple copies of a specific DNA segment.

Gel Electrophoresis

A method for separating DNA fragments based on size and charge.

Enzymes

Proteins that act as catalysts to speed up biochemical reactions.

Active Site

The region on an enzyme where substrates bind and undergo a chemical reaction.

Photosynthesis

The process by which plants convert light energy into chemical energy (glucose).

Chlorophyll

The primary pigment in plants that absorbs light for photosynthesis.

Cellular Respiration

The process of breaking down glucose in the presence of oxygen to release energy.

Fermentation

An anaerobic process that allows cells to produce ATP without oxygen.

Lactic Acid Fermentation

A type of fermentation occurring in animals, producing lactic acid.

Alcoholic Fermentation

A fermentation process in which glucose is converted to ethanol and carbon dioxide, used by yeasts.

What problems do cells encounter as they grow in size?

As cells grow, they encounter problems related to surface area to volume ratio, diffusion rates, and DNA overload.

What is binary fission? What type of reproduction is it?

Binary fission is a type of asexual reproduction in which a cell divides into two identical daughter cells. It is a form of asexual reproduction because it involves only one parent and produces offspring that are genetically identical to the parent.

Compare asexual and sexual reproduction

Asexual reproduction involves one parent, resulting in genetically identical offspring, and is faster. Sexual reproduction involves two parents, resulting in genetically diverse offspring, and is slower.

Do cells seek a large or small SA:V? Why?

Cells seek a large surface area to volume ratio (SA:V) to optimize the exchange of nutrients and waste with their environment. A higher SA:V allows for more efficient diffusion.

What are the FOUR stages of a cell’s life cycle? Provide them in the order that they occur.

The four stages of a cell’s life cycle are Interphase, Mitosis, Cytokinesis, and G0 (if applicable).

What key processes happen in each of the phases of a cell’s life cycle?

Interphase involves cell growth and DNA replication. Mitosis involves the separation of chromosomes. Cytokinesis involves the division of the cytoplasm. G0 phase is a resting or non-dividing state.

What does cytokinesis mean? When does it occur in the cell life cycle?

Cytokinesis means cell division, specifically the division of the cytoplasm. It occurs at the end of mitosis.

What is G0 phase of a cell life cycle?

G0 phase is a state where cells exit the cell cycle and do not actively divide. It is a period of cell cycle arrest.

What is apoptosis?

Apoptosis is programmed cell death, a process where cells self-destruct.

Describe what G0 phase of the cell cycle is and how it could be healthy/helpful for cells.

G0 phase allows cells to perform their functions without dividing, which is crucial for specialized cells like neurons. It can be healthy by preventing unnecessary cell division.

Describe how apoptosis can be beneficial (for good).

Apoptosis is beneficial because it removes damaged or unnecessary cells, preventing tumors and maintaining tissue homeostasis.

Cancer is defined as uncontrolled cell cycling. How do we currently treat cancer and what are some of the unintended consequences of that treatment?

Current cancer treatments like chemotherapy and radiation target rapidly dividing cells, but they also harm healthy cells, leading to side effects like nausea and hair loss.

Interphase includes what phases of the cell cycle? What are the main roles of each of those phases?

Interphase includes G1, S, and G2 phases. G1 involves cell growth, S involves DNA replication, and G2 prepares the cell for division.

Checkpoints are ways that a cell cycle is controlled. How many checkpoints are there, where do they occur, and what things are “checked” at each cell cycle checkpoint?

There are three main checkpoints: G1, G2, and M checkpoints. They check for DNA damage, proper chromosome replication, and correct spindle attachment.

What is apoptosis? How can cell death be a good thing?

Apoptosis is programmed cell death. It is beneficial because it removes damaged or unnecessary cells, preventing tumors and maintaining tissue homeostasis.

What is cancer? Tumor? What’s the difference between a benign and a malignant tumor

Cancer is uncontrolled cell cycling. A tumor is a mass of abnormal cells. A benign tumor is non-invasive, while a malignant tumor is invasive and can metastasize.

Mitosis occurs in four (PMAT) steps followed by cytokinesis. What are the four stages of PMAT?

The four stages of PMAT are Prophase, Metaphase, Anaphase, and Telophase.

Prophase is the first step of mitosis. What are some things that are occurring in the cell that begin the cell division process?

In prophase, the nuclear envelope breaks down, chromatin condenses into chromosomes, and the spindle begins to form.

What is the key event happening in metaphase of mitosis?

The key event in metaphase is the alignment of chromosomes along the metaphase plate.

What is happening in anaphase of mitosis? Be sure to be able to reference and what is meant by SISTER CHROMATIDS.

In anaphase, sister chromatids are separated and pulled to opposite poles of the cell. Sister chromatids are identical copies of a chromosome.

What is happening in telophase of mitosis? It’s basically the opposite of what phase?

In telophase, the nuclear envelope reforms, chromosomes decondense back into chromatin, and the spindle disappears. It is basically the opposite of prophase.

What is happening in cytokinesis of the cell cycle? Can you recognize and talk about the CLEAVAGE FURROW that is a term that goes with this step?

In cytokinesis, the cytoplasm divides, resulting in two separate daughter cells. The cleavage furrow is the indentation that forms as the cell is pinching in two.

What is a ligand? How does it relate to a receptor?

Ligand: A molecule that binds to a receptor.

What are the FOUR types of signaling? The prefixes of their names matter. Tell what they mean and provide an example for each type of cell signaling/communication.

The four types of signaling are: Direct Contact (e.g., gap junctions), Paracrine (local) signaling (e.g., growth factors), Endocrine (hormonal) signaling (e.g., insulin), and Synaptic signaling (e.g., neurotransmitters).

How could you speed up cell communication? Slow it down?

Cell communication can be sped up by increasing the concentration of ligands or receptors, or slowed down by using inhibitors or reducing the number of receptors.

Cell communication occurs in three steps referred to as a signal transduction pathway. What are those steps in the order that they occur?

The three steps of a signal transduction pathway are Reception, Transduction, and Response.

How might a ligand be received differently if it is hydrophobic or hydrophilic?

A hydrophobic ligand can pass through the cell membrane and bind to intracellular receptors, while a hydrophilic ligand binds to receptors on the cell surface.

What happens to a receptor after a ligand has been received?

After a ligand is received, the receptor undergoes a conformational change, initiating a signaling cascade.

What is transduction? What does it do in a communication pathway?

Transduction is the process of converting a signal into a form that can bring about a cellular response. It often involves a cascade of molecular interactions.

What are some cellular responses that could happen in cell communication? Can you provide some specific examples of cells communicating?

Cellular responses can include changes in gene expression, enzyme activation, or cell movement. Examples include insulin signaling leading to glucose uptake or growth factors stimulating cell division.

Compare and contrast Mitosis and Meiosis

Mitosis produces two identical diploid cells, while meiosis produces four genetically diverse haploid cells. Mitosis is for growth and repair, while meiosis is for sexual reproduction.

What is crossing over and when does it occur in Meiosis?

Crossing over is the exchange of genetic material between homologous chromosomes and occurs during prophase I of meiosis.

Random assortment provides variety, when does this show up in the Meiosis process?

Random assortment occurs during metaphase I of meiosis when homologous chromosomes line up randomly.

What is pulled apart in Anaphase I of Meiosis and what is pulled apart in Anaphase II of Meiosis?

In anaphase I of meiosis, homologous chromosomes are pulled apart. In anaphase II of meiosis, sister chromatids are pulled apart.

How many cells are produced as a result of Meiosis? Are those cells identical? Are they haploid or diploid?

Meiosis produces four cells. These cells are not identical and are haploid.

If you take into account crossing over, random assortment, and random fertilization approximately how many unique combinations could you produce in terms of variety of sex cells (sperm or egg)?

Taking into account crossing over, random assortment, and random fertilization, approximately 8.4 million unique combinations can be produced in terms of variety of sex cells.

What is nondisjunction?

Nondisjunction is the failure of chromosomes to separate properly during meiosis.

What is a karyotype?

A karyotype is a visual representation of an organism's chromosomes.

What is a monosomy? Trisomy?

Monosomy is the condition of having one chromosome missing from a pair. Trisomy is the condition of having an extra chromosome.

What are some example disorders that are due to nondisjunction?

Examples of disorders due to nondisjunction include Down syndrome (trisomy 21), Turner syndrome (monosomy X), and Klinefelter syndrome (XXY).

What is the difference between a character and a trait?

A character is a heritable feature, while a trait is a variant of a character.

What does it mean to be true-breeding?

True-breeding means that the organism consistently produces offspring with the same traits.

What does it mean to be dominant? Recessive? How are they represented with letters?

Dominant means the trait that is expressed when present. Recessive means the trait that is only expressed when the dominant allele is absent. Dominant alleles are represented with uppercase letters, and recessive alleles with lowercase letters.

What five principles did we gain from Mendel’s work in inheritance?

The five principles gained from Mendel’s work are: 1. Law of Segregation, 2. Law of Independent Assortment, 3. Concept of Dominance, 4. Concept of Recessive, 5. Unit Factors in Pairs.

What is the difference between a genotype and phenotype? Be able to use the terms homozygous dominant, homozygous recessive and heterozygous.

Genotype is the genetic makeup of an organism, while phenotype is the physical expression of the genotype. Homozygous dominant has two dominant alleles, homozygous recessive has two recessive alleles, and heterozygous has one dominant and one recessive allele.