Cell Biology and Mendelian Genetics Lecture Notes

Vocabulary practice flashcards covering cell structure, membrane transport, cell organelles, mitosis, meiosis, and Mendelian inheritance principles.

Cell Membrane

The outermost component of a cell that encloses the cytoplasm, forms the boundary between material inside and outside the cell, supports cell contents, and acts as a selective barrier.

Fluid Mosaic Model

The structural model of the cell membrane composed of phospholipids forming a double layer, with hydrophilic regions contacting aqueous fluids inside and outside and hydrophobic regions in the interior.

Organelles

Specialized structures or membrane-bound compartments within the cell that perform specific functions.

Passive Membrane Transport

Transport mechanisms that do not require the cell to expend energy (does not use ATP), including diffusion, osmosis, and facilitated diffusion.

Diffusion

The movement of particles from an area of high concentration to an area of low concentration without the expenditure of ATP.

Osmosis

The diffusion of water across a membrane that does not require the expenditure of ATP.

Aquaporin

A hydrophobic intrinsic membrane protein that forms channel pores in cell membranes to facilitate the transport of water.

Hypotonic Solution

A solution that has less tone or osmotic pressure than the cell.

Isotonic Solution

A solution in which the cell neither shrinks nor swells.

Hypertonic Solution

A solution that has a higher concentration of solutes and a lesser concentration of water compared to the cell.

Facilitated Diffusion

A carrier-mediated transport process that moves substances across the cell membrane from an area of higher concentration to lower concentration without requiring ATP.

Active Transport

A carrier-mediated process that moves substances across the cell membrane from regions of lower concentration to higher concentration against a concentration gradient, requiring energy usually in the form of ATP.

Endocytosis

The movement of materials into the cell by the formation of a vesicle, which requires ATP.

Phagocytosis

A type of endocytosis referred to as 'cell-eating' in which solid particles are ingested.

Pinocytosis

A type of endocytosis referred to as 'cell-drinking' that involves the intake of liquid or particles.

Receptor-Mediated Endocytosis

The transport of a substance into the cell via vesicle formation after binding with a receptor molecule.

Exocytosis

The movement of substances out of cells by vesicles, requiring ATP.

Endoplasmic Reticulum

A series of membranes forming sacs and tubules that extend from the outer nuclear membrane into the cytoplasm.

Rough Endoplasmic Reticulum

Endoplasmic reticulum studded with ribosomes that serves as a transport channel for synthesized proteins and is a major site of protein synthesis.

Smooth Endoplasmic Reticulum

Endoplasmic reticulum without ribosomes that serves as the major site of lipid synthesis and detoxification of chemicals within cells.

Ribosomes

Organelles where proteins are produced; known as the protein builders or protein synthesizers of the cell.

Golgi Apparatus

A series of closely packed membrane sacs that collect, modify, package, and distribute proteins and lipids produced by the endoplasmic reticulum.

Secretory Vesicles

Membrane-bound sacs that carry substances from the Golgi apparatus to the cell membrane, where their contents are released.

Lysosomes

Membrane-bound vesicles containing enzymes that break down phagocytized material or destroy foreign materials.

Peroxisomes

Membrane-bound vesicles containing enzymes that break down fatty acids, amino acids, and hydrogen peroxide.

Nucleus

An organelle located near the center of the cell, bounded by a nuclear envelope consisting of an outer and an inner membrane.

Cytoskeleton

A framework made of proteins that supports the cell, holds organelles in place, and enables the cell to change shape.

Microtubules

Cytoskeletal components with the largest diameter that support cell cytoplasm, assist in cell division, and form essential components of cilia and flagella.

Microfilaments

Cytoskeletal components with the smallest diameter that are involved in cell movement.

Intermediate Filaments

Cytoskeletal structures smaller in diameter than microtubules but larger than microfilaments that provide mechanical support to the cell.

Centrosome

A small region of cytoplasm adjacent to the nucleus that contains the centrioles.

Centrioles

Structures located within the centrosome that are made of microtubules.

Cilia

Projections from the cell surface that vary in number and are capable of moving.

Flagella

Structures longer than cilia that usually occur only one per cell and are found on the sperm cell surface.

Cell Division

The formation of two daughter cells from a single parent cell.

Mitosis

A form of cell division where new cells necessary for growth and tissue repair are formed.

Meiosis

A form of cell division where sex cells necessary for reproduction are formed.

Prophase

The stage of cell division during which chromatin condenses, nucleoli disappear, and the nuclear membrane breaks down.

Metaphase

The stage of cell division where chromosomes are moved to the equator (metaphase plate) and are attached to spindle fibers.

Anaphase

The stage of cell division where sister chromatids separate and are moved toward opposite poles of the spindle by spindle fibers.

Telophase

The stage of cell division during which chromosomes disperse, the nuclear membrane and nucleoli reform, and the spindle disappears.

Apoptosis

Programmed cell death; a normal process by which cell numbers within various tissues are regulated and controlled.

Interphase

The phase during which DNA is replicated by separating its two strands so each serves as a template to produce a new strand of DNA.

Pisum sativum

The garden pea species studied by Gregor Mendel to investigate the natural laws governing plant hybrids.

True-Breeding Strain

A strain that continues to produce the same trait after several generations of self-fertilization.

Hybridization

A breeding cross between distinct plants, such as a cross between a purple-flowered plant and a white-flowered plant.

Cross-Hybridization

Mating between two distinct individuals with different characteristics.

Self-Fertilization

Fertilization where male and female gametes are derived from the same parent.

Character

A general physical characteristic of an organism, such as eye color.

Trait (Variant)

The specific properties used to describe a character, such as blue eyes.

Allele

An alternate form of a gene or gene variant found at a corresponding position on homologous chromosomes.

Genotype

The alleles present in an organism for a particular trait, represented by a pair of letters where one code comes from the mother and the other from the father.

Phenotype

How a trait physically shows up or is expressed in an organism.

Homozygous

Having two identical alleles in the genotype (e.g., true-breeding).

Heterozygous

Having two different alleles in the genotype (non-true breeding or hybrid).

Law of Dominance

Mendelian principle stating that in a cross of parents pure for contrasting traits, only one form of the trait will appear in the next generation.

Dominant Allele

An allele whose phenotypic expression overpowers the effect of a second form of the same gene.

Recessive Allele

An allele whose effects are concealed in the offspring by the presence of a dominant allele.

$F_1$ Generation

The first generation of offspring produced from a cross of the parental generation.

Punnett Square

A diagram used to show how two alleles of a gene combine during a cross between two individuals.

Law of Segregation

Mendel's law stating that two copies of a gene separate from each other during transmission from parent to offspring, resulting in only one copy of each gene being present in a gamete.

Law of Independent Assortment

Mendelian principle stating that alleles for genes on different chromosomes assort independently, such that the chance of inheriting one does not affect the chance of inheriting the other.