Chapter 6: Overview of Cell Biology

Vocabulary flashcards generated from the cell biology lecture notes covering organic and inorganic compounds, cell structures, DNA/RNA functions, and cell division processes.

Homeostasis

The ability of the body to operate in normal function despite any changes in its environment.

Radiosensitivity of Immature Cells

Cells that are immature, undifferentiated, and not specialized, making them more sensitive to radiation.

Radiosensitivity of Mature Cells

Cells that are mature, specialized, and differentiated, making them less sensitive to radiation.

Organic Compounds

Major classes of compounds that compose the cell and contain carbon; includes proteins, carbohydrates, lipids (fats), and nucleic acids.

Carbon

The basic constituent of all organic matter that makes life possible when combined with hydrogen, nitrogen, and oxygen.

Proteins

Elementary building blocks that constitute $15FS_PERCENT$ of cell content, essential for growth, structure, new tissue construction, cell repair, and enzyme activity.

Amino Acids

The $22$ different molecular building blocks whose arrangement sequence determines the precise function of each protein macromolecule.

Structural Proteins

Proteins found in tissues such as muscle that provide cellular structure and support, such as collagen.

Enzymatic Proteins

Proteins that act as enzymes to control and accelerate functions like digestion, food breakdown, and respiration.

Carbohydrates

Organic compounds composed of sugars containing carbon, hydrogen, and oxygen that serve as fuel for cellular energy.

Lipids

Organic molecules including triglycerides and steroids (such as cholesterol) that provide energy storage, insulation, protection, and cellular structure.

Nucleic Acids

Macromolecules composed of nucleotide units consisting of a sugar, a phosphate, and nitrogenous bases.

DNA (Deoxyribonucleic Acid)

The master chemical in the nucleus, formed by two long sugar-phosphate chains in a double-helix structure linked by nitrogenous base pairs, containing all genetic info for cell function and replication.

Messenger RNA (mRNA)

A single-stranded RNA molecule that copies genetic information from DNA inside the nucleus and travels to the cytoplasm to direct protein synthesis, replacing thymine with uracil.

Transfer RNA (tRNA)

A type of RNA, existing in at least $22$ types, that receives genetic code from mRNA and attaches individual amino acids to ribosomes in specific sequences.

Ribosomal RNA (rRNA)

A type of RNA that functions to assist in linking mRNA to the ribosome to facilitate protein synthesis.

Inorganic Compounds

Compounds that do not contain carbon, such as acids, bases, and salts (electrolytes), occurring in nature independent of living things.

Water

The most abundant inorganic substance in the human body, comprising approximately $80\%$ to $85\%$ of the body's total weight.

Mineral Salts

Inorganic substances within the cell that maintain osmotic pressure, proper water proportion, cell performance, energy creation, and impulse conduction along nerves.

Cell Membrane

The outer barricade protecting cellular contents, controlling the passage of water and materials into and out of the cell, eliminating waste, and refining materials for energy.

Endoplasmic Reticulum

The cellular highway that enables the cell to communicate with the extracellular environment and transfers food from one part of the cell to another.

Golgi Apparatus

The freight-hauling organelle that unites large carbohydrate molecules with proteins to form glycoproteins and transports enzymes and hormones outside the cell.

Mitochondria

The power-generating stations of the cell that produce energy for cellular activity by breaking down nutrients through oxidation.

Lysosomes

Organelles containing hydrolytic enzymes that digest and dispose of large particles such as bacteria and food, as well as smaller waste particles.

Ribosomes

The manufacturing facilities of the cell that synthesize the various proteins required by the cell.

Centrosomes

Organelles that play an important role in organizing the formation of the mitotic spindle during cell division.

Nucleus

The administrative center of the cell containing DNA and proteins, which controls cell division, multiplication, biochemical reactions, and protein synthesis.

Nucleolus

An area within the nucleus that holds a large amount of RNA and synthesizes ribosomes.

Mitosis

The process of somatic cell division in which the nucleus divides first, followed by the cytoplasm, resulting in two identical daughter cells.

Meiosis

The process of reduction cell division occurring in genetic cells that reduces the chromosome number in each daughter cell to half of the parent cell.

Cellular Life Cycle Phases

The four distinct, identifiable phases of a cell's life cycle: M, $G_1$, S, and $G_2$.

Subphases of Mitosis

The four sequential subphases of mitotic division: prophase, metaphase, anaphase, and telophase.

Monozygotic Twins

Identical twins resulting from a single fertilized egg.

Dizygotic Twins

Fraternal twins resulting from two separately fertilized eggs.