Introduction to Zoology, Cell Biology, Histology, Integumentary, and Skeletal Systems

Vocabulary practice flashcards covering cell theories, organelles, cell division, animal tissues, the integumentary system, and the skeletal system based on the lecture transcript.

Divine Creation Theory

The belief that life was created by the Almighty God, based on the book of Genesis of the Holy Bible.

Cosmozoic or Interplanetary Theory

The theory that life originated from protoplasm in the form of a resistant spore coming from outer planets propelled by radiation pressure.

Abiogenesis or Spontaneous Generation Theory

The belief that life originated spontaneously from non-living materials.

Chemical Evolution of Life Theory

The hypothesis (Oparin-Haldane Hypothesis and Miller-Urey Experiment) that life appeared in the warm, primitive ocean and was heterotrophic rather than autotrophic.

Cell Theory

States that the cell is the unit of structure and function of all living things and all living cells come from pre-existing cells.

Mycoplasma

The smallest cell, a type of bacterium ranging from about $1\text{--}100\text{ }\frac{1}{1000}\text{ mm}$ or 1\text{--}100\text{ }\text{̦} (1\text{--}100\text{ }\text{̦}\text{m}) in diameter.

Prokaryotic Cells

Cells without a true nucleus that have their nuclear materials (nucleoid) mixed with the protoplasm containing only single chromosomes (DNA only).

Eukaryotic Cells

Compartmentalized cells containing organelles and inclusions with specific functions, and a distinct nucleus enclosed by a nuclear membrane.

Plasma Membrane

The outer boundary of the cell composed of a molecular bilayer of phospholipids that helps maintain homeostasis, gives strength, shape, and protection.

Cytosol

The thick semi-fluid portion of the cytoplasm, also called intracellular fluid (ICF), containing soluble proteins, nutrients, ions, and suspended organelles.

Inclusions

Temporary cell structures that contain secretions and storage products.

Nucleolus

A dense organelle found within the nucleus where ribosomes are formed.

Ribosome

The organelle where amino acids are bound together; commonly called the site of protein synthesis.

Golgi Apparatus

A series of flattened sacs curled at the edges where proteins and lipids are processed and packaged.

Lysosome

A drop-like sac full of enzymes that moves about in the cytoplasm and is used by the cell for digestion.

Centrioles

Cylinder-like organelles composed of microtubules that are only found in animal cells.

Mitochondrion

The 'powerhouse of the cell,' where energy is stored and released, serving as the site for cellular respiration.

Krebs Cycle

Also called tricarboxylic acid (TCA) cycle or citric acid cycle; a series of biochemical reactions in the mitochondrial matrix releasing energy from acetyl CoA.

p53

A critical component of the DNA damage response, especially during the $G_1$ phase checkpoint.

Leptonema

Substage of Prophase I appearing as thin threads where homology search happens.

Zygonema

Substage of Prophase I where homologous chromosomes begin to pair up and undergo synapsis.

Pachynema

Substage of Prophase I where homologous chromosomes fully synapse into tetrads and undergo genetic recombination.

Diplonema

Substage of Prophase I where paired homologous chromosomes begin to separate and repel, remaining connected only at chiasmata.

Diakinesis

Substage of Prophase I marked by maximum condensation of chromosomes and terminalization of chiasmata.

Gametogenesis

The biological process by which diploid ($2n$) precursor cells undergo division and differentiation to form mature haploid ($n$) gametes.

Simple Epithelia

Tissues made up of a single layer of cells found in areas where transport processes such as osmosis, diffusion, filtration, secretion, and absorption occur.

Stratified Epithelia

Tissues made up of two or more layers of cells found in areas subjected to considerable wear and tear.

Pseudostratified Epithelium

Tissue made up of a single layer of cells with nuclei at different levels, creating a stratified appearance.

Areolar Connective Tissue

The most widely distributed connective tissue; soft and pliable, cushioning and protecting body organs.

Hyaline Cartilage

The most abundant and widespread cartilage, featuring fine collagen fibers embedded in a blue-white glassy matrix covered by perichondrium.

Osteon

Also called Haversian system; consists of a series of concentric circles of matrices around a central Haversian canal in compact bone.

Osteoclasts

Differentiated macrophages responsible for bone resorption and remodeling.

Endochondral Ossification

Bone development process where bone forms from a pre-existing cartilage model.

Intramembranous Ossification

Bone development process where bone forms directly from sheets of embryonic cells.

Stratum Corneum

Epidermal sublayer consisting of flat, keratinized, dead cells serving as a water-repellent barrier; present in all vertebrates except fishes.

Stratum Lucidum

Epidermal sublayer consisting of several rows of clear, flat, dead cells containing eleidin; found only in thick skin of mammalian palms and soles.

Langerhans Cells

Bone marrow-derived macrophages in the epidermis that ingest foreign substances and present them to white blood cells.

Merkel Cells

Epidermal cells associated with sensory neurons to form Merkel disks, which function as sensory receptors for object contact.

Hydrostatic Skeleton

The simplest skeleton type, consisting of a volume of incompressible fluid enclosed in a body cavity surrounded by muscles.

Synarthroses

Immovable joints, comprising sutures, gomphoses, and synchondroses.

Amphiarthroses

Slightly movable joints, comprising syndesmoses and sympheses.

Diarthroses

Freely movable or synovial joints characterized by two bones separated by a joint cavity.