BIOSCI 107 Definitions Flashcards
Integumentary
Bodily system consisting of the skin and associated structures such as the glands, hair, nails, scales etc.
Tendon
Tough band of fibrous connective tissue that usually connects muscle to bone.
Aponeurosis
A flat sheet or ribbon of tendon-like material that anchors a muscle.
Cartilage
Strong, flexible type of connective tissue.
Thymus
Main organ of the lymphatic system.
Kidneys
Main organs of the urinary system.
Lymphatic System
A system that is comprised of lymph nodes, lymph vessels, lymphoid tissues, and lymph.
Epithelial
A membranous animal tissue made up of one or more layers of cells closely packed together.
Connective
It connects, supports, or surrounds other tissues and organs.
Muscle
Organ made up of muscle tissues, or the tissue itself, enabling contraction or tension in an animal body to effect movement or locomotion.
Nervous
A system of the body that receives, interprets, and responds to stimuli from inside and outside the body.
Apical Membrane
The surface of a plasma membrane that faces inward to the lumen.
Lateral
Side of the body or a body part.
Basal
Relating to, situated at, or forming the base.
Basement Membrane
Extracellular matrix characteristically found under epithelial cells.
Exocrine Glands
Secrete onto external surfaces and into ducts.
Endocrine Glands
Hormones or precursors into intestinal fluid.
Simple
Single layer.
Squamous
Flat/thin.
Keratin
Fibrous structural protein of the epithelial cells in the outermost layers of the skin.
Desmosome
Intercellular junctions that provide strong adhesion between cells.
Actin
Actin and the protein myosin together make up the contractile units (called sarcomeres) of skeletal muscle fibers.
Connexon
An assembly of six proteins called connexins.
Hemidesmosome
A type of anchoring junction between neighbouring cells.
Transitional
Subject to great mechanical change due to contraction and distention.
Extra Cellular Matrix
A collection of extracellular molecules secreted by cells that provides structural and biochemical support to the surrounding cells.
Proteoglycans
The “filler” substance existing between cells in an organism (Protein + GAG).
Glycosaminoglycans
Long unbranched polysaccharides consisting of a repeating disaccharide unit.
Collagen Fibres
Protein fibre that provides strength and cushioning to many different areas of the body, including the skin.
Reticular Fibres
A type of fibre in connective tissue which serves as a supporting mesh in soft tissues such as liver and bone marrow.
Elastic Fibres
A type of fibre that is thick and yellowish, and composed primarily of elastin.
Marfan Syndrome
A genetic disorder that affects the body’s connective tissue - long fingers, legs etc.
Fibroblasts
A type of cell that synthesizes the extracellular matrix and collagen, the structural framework (stroma) for animal tissues, and plays a critical role in wound healing.
Adipocytes
The primary cell type of adipose tissue and play a key role in maintaining energy homeostasis.
Mesenchymal Cells
Multipotent stromal cells that can differentiate into a variety of cell types - osteoblasts, chondrocytes, myocytes, adipocytes.
Areolar Tissue
A connective tissue in which fibres are loosely arranged in a net or meshwork.
Adipose
The tissue stores energy in the form of fat within the adipocytes.
Osteogenic Cells
Mesenchymal stem cells, become osteoblasts.
Osteoblasts
Bone forming cells.
Osteocytes
Mature bone cells derived from osteoblasts - maintain bone tissue.
Osteoclasts
Formed from blood monocyte fusion, break down bone.
Lamellae
Concentric rings of mineral salts for hardness.
Lacunae
Small spaces between lamellae that contain mature bone cells (osteocytes).
Canaliculi
Minute canals.
Central Canal
Contains blood cells and nerves.
Myofibrils
Contractile unit of a striated muscle.
Myofilaments
Threadlike structures that comprise the myofibril inside the muscle cell .
Sacromere
Basic functional unit of a myofibril, separated by Z discs.
Epimysium
Anatomical muscle.
Perimysium
Fascicles.
Endomysium
Muscle fibres ‘cell’.
A Band
Thick filaments.
I Band
Thin filaments.
H Zone
Thick filaments.
M Line
Holds thick filaments together.
Z Disc
Between sacromeres.
Intercalated Discs
Join fibres end to end.
Contraction
Tension transmitted to intermediate filaments twisting cells about stable ‘rods’.
Neurons
Specialized cell that forms the basis of the nervous system - transmits signals throughout the body.
Unipolar Neuron
A neuron that has one main process, the axon, extending from its cell body.
Anaxonic Neuron
A neuron where the axon cannot be differentiated from the dendrites.
Neuroglia
Non-neuronal cells of the nervous system.
Astrocytes
The largest and most numerous neuroglial cells in the brain and spinal cord.
Oligodendrocytes
Insulating multilayered myelin sheath (protein lipid layer) around CNS axons.
Microplia
Phagocytic protection.
Ependymal Cells
Produce cerebrosomal fluid line CSF-filled ventricles (brain) and central canal of the spinal cord.
Myelinating Schwann
Cells that wrap around axons of motor and sensory neurons to form the myelin sheath.
Cytosol
The fluid in which organelles of the cell reside.
Rough ER
Sorting and Packaging of proteins.
Smooth ER
Production of lipids/carbs, housing unit for tissue specific proteins.
Peptide
Less than 50 amino acids.
Protein
More than 50 amino acids.
Chaperone
Fold protein as it emerges from ribosome.
DNA
Heritable material used to store and transmit information from generation to generation.
RNA
Acts as a messenger to allow the information stored in the DNA to be used to make proteins.
Transcription
Synthesis of RNA from a DNA template.
Exons
Coding regions that form part of final mRNA product.
Introns
Intervening non coding sequences (not in final mRNA).
A Site
Acceptor site for an aminoacyl tRNA, binds to mRNA codon.
P Site
Peptide bond forms that adds an amino acid to the growing polypeptide chain.
E Site
Where tRNAs no longer bound to an amino exit the ribosomes.
Wobble Hypothesis
Tells you about amounts of amino acids in cells.
Quaternary
Homodimer or heterodimer.
Acetyl CoA
Delivers the acetyl group to the citric acid cycle (Krebs cycle) to be oxidized for energy production.
Interphase
Prophase, Prometaphase, Metaphase, Anaphase, Telophase, Cytokinesis.
Prophase
Chromatids of matching chromosomes made.
Prometaphase
Spindle interacts with chromosomes in cells (looks for kinetochore).
Metaphase
Chromosomes are aligned in correct orientation thanks to kinetochore.
Anaphase
Chromosomes are pushed to ends of cell.
Telophase
Formation of two nuclei.
Cytokinesis
Barrier forms, making two cells.
Methylation
Addition of a methyl group.
Acetylation
Addition of an acetyl group.
Biotinylation
Addition of biotin.
Carboxylation
Addition of a carboxylic acid group.
Carbohydrate
Addition for membrane bound proteins.
Cleavage
Splitting or dividing of a cell.
Glycolysis
One glucose molecule is broken down to form two molecules of pyruvic acid.
Kreb’s Cycle
A cycle of enzyme-catalyzed reactions in living cells that is the final series of reactions of aerobic metabolism - ATP is formed.
Fertilisation
A complex process that involves the fusion of gametes/their nuclei and the activation of embryo development.
Cleavage
The series of mitotic divisions of the zygote.
Blastomeres
Cells formed through cleavage.
Compaction
Where blastomeres become tightly packed.
Cavitation
Where the morula is transformed from a solid ball of cells to a hollow ball of cells.
Zona Pellucida
Thick transparent membrane surrounding a mammalian ovum before implantation.
Hypoblast
Primitive endoderm.
Epiblast
Outermost layer of an embryo before it differentiates into ectoderm and mesoderm.
Yolk Sac
A sac lacking yolk in the early embryo.
Gastrulation
The process by which the bilaminar embryo is transformed into one that has 3 germ layers.
Primitive Streak
Faint streak which is the earliest trace of the embryo in the fertilised ovum.
Rostrally
Towards the head.
Ectoderm
Top layer.
Mesoderm
Middle layer.
Endoderm
Underlying layer.
Oropharyngeal Membrane
Depression of the head end of the trilaminar disc.
Cloacal Membrane
Depression formed at the caudal end of the trilaminar disc.
Organiser
Regions that secrete molecules that act at a distance, influencing the differentiation of different body parts.
Notochord
A cartilaginous skeletal rod supporting the body.
Somites
Any of the paired block-like segments of mesoderm, occurring dorsally, alongside the neural tube.
Sclerotome
Part of the somite closest to the neural tube and notochord.
Syndetome
Gives rise to tendons.
Myotome
Give rise to all skeletal muscles (not head).
Dermatome
Region underlying the ectoderm.
Non-Neural Ectoderm
Gives rise to the rest of the ectodermal structures of the embryo - epidermis of skin.
Neural Crest
Small group of cells differentiated at the outside edge of the neural plate.
Telencephalic Vesicle
Gives rise to forebrain.
Mesencephalic Vesicle
Gives rise to midbrain.
Rhombencrphalic Vesicle
Gives rise to hindbrain.
Branchial Arches
Give rise to the structures of the head and neck.
Facial Prominences
5 initial swellings on embryos face.
Morphogenetic
Shape developing.
Allantois
Extra-embryonic membrane.
Ectopic Pregnancies
When the embryo impacts in inappropriate positions.
Tubal Pregnancies
When the blastocyst hatches from the zona pelucida while still in the uterine tube.
Syncytial Trophoblast
Epithelial covering of the highly vascular embryonic placental villi.
Lacunae
Small space filled with mother’s blood.
Amnion
A thin, membranous sac filled with a watery fluid.
Extra-Embryonic Coelom
Single large cavity formed from a series of smaller cavities in the extra-embryonic mesoderm.
Mesodermal Stalk
Stalk of extra-embryonic mesoderm that attaches the ball on the inside with the ball on the outside (becomes umbilical cord).
Syncytium
Continuous cytoplasmic mass.
Decidua
Inner layer of the wall of the uterus.
Chorion
Part of the placenta, includes syncytial trophoblast, cellular trophoblast, extra-embryonic mesoderm.
Placenta
Includes chorion + decidua.
