Exam 3-6 review guide Flashcards
proteins that catalyze specific biochemical reactions
Enzymes
the buildup of larger molecules from smaller ones and requires energy
Anabolism
the breakdown of larger molecules into smaller ones and releases energy
Catabolism
anabolic process that joins small molecules by releasing the equivalent of a water molecule; synthesis
Dehydration Synthesis
an example of catabolism; it decomposes carbohydrates, lipids, and proteins, and splits a water molecule in the process
Hydrolysis
The target of enzyme action
Substrate
The part of an enzyme molecule that binds a substrate
Active site
A small molecules or ion that must combine with an enzyme for activity
Cofactor
A nonprotein organic molecule required for the activity of a particular enzyme
Coenzyme
An ability to move something and thus do work
Energy
Process by which oxygen combines with another chemical; the removal of hydrogen it the loss of electrons; opposite of reduction
Oxidation
The energy releasing breakdown of glucose to produce 2 pyruvic acid molecules
Glycolysis
Series of chemical reactions that oxidizes certain molecules, releasing energy
Citric acid cycle/ Krebs cycle
Series of metabolic reactions that capture the energy in the bonds of nutrient molecules as ATP
Electron transport chain
Organic molecule that stores and released energy, which may be produced in cellular processes
ATP
The complete, emergy-releasing, breakdown off glucose to carbon dioxide and water, in the presence of oxygen
Aerobic respiration
A sequence of enzyme-controlled reactions
Metabolic pathway
Molecules that hold information in the form of genetic code
DNA
The portions of DNA molecules that contain the genetic information for making particular proteins
Genes
The complete set of genetic instructions in a cell
Genome
Production of an exact copy of a DNA molecule
Replication
Correspondence between DNA base triplets and particular amino acids
Genetic code
Copying DNA to RNA
Transcription
The type of RNA that carries a gene’s message out of the nucleus
Messenger RNA (mRNA)
A single stranded molecule whose nucleotides each include the sugar ribose, a phosphate group, and a nitrogenous base (adenine, uracil, guanine, or cytosine)
RNA
Three-base sequences
Codon
RNA to amino acid
Translation
An RNA molecule that correctly aligns amino acids
Transfer RNA (tRNA)
The three nucleotides in the tRNA
Anticodon
The slowest step in a metabolic pathway or series of chemical reactions, which determines the overall rate of the other reactions in the pathway. The first enzyme in a series; requires the most activation energy
Rate-limiting enzyme
The set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.
Cellular respiration
Glycolysis that does not require oxygen
Anaerobic respiration
An ATP molecule that has lost its terminal phosphate
ADP
Joins together nucleotides in a DNA sequence; they alternate to form the outside of the DNA structure
Sugar-phosphate backbone
Projects from the backbone and binds weakly to the bases of the second strand to form the rungs of the DNA structure
Nitrogen bases
describes the manner in which the nitrogenous bases of the DNA molecules align with eachother; responsible for the double-helix structure of DNA
Complimentary base pairing
an enzyme that unwinds and separates the two strands of the DNA double helix
Helicase
An enzyme that brings in new DNA nucleotides, forming complementary pairs with the exposed bases
DNA polymerase
A boundary that regulates movement of substances in and out of the cell, and is the site of much biological activity
Cell membrane
Houses the genetic material and controls cellular activities
Nucleus
Fills out the cell; contains organelles
Cytoplasm
Specialized structures within the cytoplasm
Organelles
Only certain substances can enter or leave the cell
Selectively permeable
Abundance of protein rods and tubules that form a framework in the cytoplasm
Cytoskeleton
Contains enzymes important in lipid synthesis, absorption of fats from the digestive tract, and the metabolism of drugs
Smooth endoplasmic reticulum
An organelle covered with ribosomes: A site of protein synthesis
Rough endoplasmic reticulum
A site of protein synthesis
Ribosomes
A stack of about six flattened, membranous sacs that refines, packages, and transports proteins synthesized on ribosomes associated with the ER
Golgi apparatus
The powerhouse of the cell
Mitochondria
Contains powerful enzymes that break down nutrient molecules or foreign particles
Lysosomes
These house enzymes that catalyze (speed) a variety of biochemical reactions, including synthesis of bile acids (used to digest fats)
Peroxisomes
Tiny rods of actin protein that form meshworks or bundles that provide cell movement and forms the cytoskeleton
Microfilaments
Long, slender tubes with diameter two or three times those of microfilaments; both of these form the cytoskeleton
Microtubules
During mitosis, the centrioles in this distribute chromosomes to newly forming cells
Centrosome
Motile structure attached beneath the cell membrane that propels fluid over cellular surfaces
Cilia
Motile structure attached beneath the cell membrane that enables a speed cell to move
Flagella
Membranous sacs that contain and transport various substances
Vesicles
Double membrane that separates the nuclear contents from the cytoplasm
Nuclear envelope
Dense, nonmembranous body composed of protein and RNA
Nucleolus
Fibers composed of protein and RNA and it is the site of ribosome synthesis
Chromatin
Rodlike structures that condense from chromatin in a cell’s nucleus during mitosis
Chromosomes
The movement of substances into and out of cells that do not require cellular energy
Passive transport
The process by which molecules or ions scatter or spread spontaneously from regions of high concentration to low concentrations
Diffusion
Uniformly distributed in the water
Equilibrium
A process that allows substances to pass through the lipid bilayer through the help of membrane proteins
Facilitated diffusion
A special case of diffusion that occurs whenever water molecules diffuse from a region of high to low concentration across a selectively permeable membrane
Osmosis
A solution with the same osmotic pressure as the solution (usually body fluids) with which it is compared
Isotonic
A solution with a greater osmotic pressure than the solution (usually body fluids) with which it is compared
Hypertonic
A solution with a lower osmotic pressure than the solution (usually body fluids) with which it is compared
Hypotonic
Molecules are forced from regions of higher pressure to regions of lower pressure
Filtration
Process that requires energy to move a substance across a cell membrane, usually against the concentration gradient
Active Transport
Transport of substances out of a cell in membrane bounded vesicles
Exocytosis
Process by which a cell membrane envelops a substance and draws it into the cell in a vesicle
Endocytosis
Membrane engulfs droplets of liquid from surroundings
Pinocytosis
Membrane engulfs particles from surroundings
Phagocytosis
Receptors bind specific ligands, and they are drawn into the cell
Receptor-mediated endocytosis
Period between cell divisions when a cell metabolizes and prepared to divide.
Interphase (G1, S, G2)
A form of cell division that produces two somatic cells with identical chromosome numbers as the original somatic cell
Mitosis
Stage of mitosis when chromosomes become visible
Prophase
Stage in mitosis when chromosomes align in the middle of the cell
Metaphase
Stage in mitosis when duplicate chromosomes move to opposite poles of cell
Anaphase
Stage in mitosis when newly formed cells separate
Telophase
Division of the cytoplasm
Cytokinesis
Cell specialization
Differentiation
An undifferentiated cell that can divide to yield two daughter stem cells, or a stem cell and a progenitor cell
Stem cells
Programmed cell death
Apoptosis
a thin extracellular supporting layer that separates a layer of epithelial cells from the underlying lamina propria and is composed of the basal lamina and reticular lamina
Basement membrane
Single layer of thin, flattened cells with broad and thin nuclei. It lines the air sacs of the lungs and the walls of capillaries
Simple Squamous Epithelium
single layer of cube-shaped cells with a centrally located, spherical nuclei. It covers the ovaries, the ducts of certain glands, and kidney tubules
Simple Cuboidal Epithelium
Elongated, single layer of cells. Lines the uterus and most organs of the digestive tract
Simple Columnar Epithelium
single layer of cells that appear stratified or layered, but are not. Lines the oral cavity, esophagus, vagina, and anal canal.
Pseudostratified Columnar Epithelium
many cell layers make this tissue relatively thick. Forms the outer layer of the skin (epidermis)
Stratified Squamous Epithelium
2 or 3 layers of cuoidal cells that form the lining of a lumen. Lines the larger ducts of the mammary glands, sweat glands, salivary glands, and pancreas
Stratified Cuboidal Epithelium
Several layers of cells. The superficial cells are columnar, where the basal layers consist of cuboidal cells. Found in the male urethra, the ductus deferens, and parts of the pharynx
Stratified Columnar Epithelium
composed of protein fibers, and a ground substance consisting of nonfibrous protein and other molecules, and fluid
Extracellular matrix connective tissue
large, star-shaped cells that produce fibers by secreting proteins into the extracellular matrix of connective tissues
Fibroblasts
These can move about and function as scavenger and defensive cells that clear foreign particles from tissues
Macrophages
large and widely distributed in connective tissues; prevents blood clotting
Mast cells
thick threads that are grouped in long, parallel bundles,and are flexible but only slightly elastic; holds structures together
Collagenous fibers
thin fibers that branch and form complex networks; common in the vocal cords
elastic fibers
very thin collagenous fibers; located in the spleen
reticular fibers
cells are mainly fibroblasts, and are located some distance apart. Function is to bind the skin to the underlying organs and fill spaces between muscles
loose connective tissue (areolar)
stores fat droplets in cytoplasm; functions as an insulator and cushion, and also stores energy
Adipose
forms the inner lining of the urinary bladder and lines the ureters; several layers of cuboidal cells, however it changes appearance when the tissue stretches
Transitional Epithelium
composed of cells that are specialized to produce and secrete substances into ducts or body fluids
Glandular Epithelium
glands that secrete their products into ducts that open onto surfaces, such as the skin or the lining of the digestive tract
Exocrine glands
glands that secrete their products into tissue fluid or blood
Endocrine glands
glands that release fluid by exocytosis
merocrine glands
glands that lose small portions of their glandular cell bodies during secretion
apocrine glands
glands that release entire cells that disintegrate to release cell secretions
holocrine glands
composed of thin, collagenous fibers in a three-dimensional network; helps to provide the framework for organs such as the liver and spleen
reticular connective tissue
consists of many closely packed, thick, collagenous fibers and a fine network of elastic fibers; parts of tendons and ligaments
Dense connective tissue
cartilage cells that occupy small chambers called lacunae and lie completely within the extracellular matrix
Chondrocytes
the most common type;fine collagenous fibers; found on the end of bones in many joints, in the soft part of the nose, and in the supporting rings of the respiratory passages
Hyaline Cartilage
a dense network of elastic fibers; provides the framework for the external ears and for parts of the larynx
Elastic Cartilage
a very tough tissue, a shock absorber for structures like between the individual bones of the spinal column, or in the knees
Fibrocartilage
most rigid connective tissue; internally supports body structures
Bone
transports a variety of materials between interior body cells and those that exchange substances with the external environment; maintains homeostasis
Blood
lines the body cavities that lack openings to the outside
Serous membranes
lines cavities and tubes that open to the outside of the body
Mucous membranes
lines joints; composed entirely of connective tissues
Synovial membranes
the skin
Cutaneous membranes
Voluntarily controlled, striated, several nuclei per cell, found attached to bones, and contains long, nonbranching cylindrical cells
Skeletal muscle tissue
Involuntarily controlled, single nucleus per cell, found in the walls of the stomach, uterus, and arteries, contains spindle-shaped cells, and changes the internal volume of an organ as it contracts
Smooth muscle tissue
involuntarily controlled, striated, single nucleus, contains branching cylindrical cells, intercalated discs, and only in the heart
Cardiac muscle tissue
nerve cells; they sense certain types of changes in their surroundings
neurons
support and bind the components of the nervous tissue, carry on phagocytosis, and help supply nutrients to neurons by connecting them to blood vessels
neuroglial cells
found in the brain, spinal cord, and peripheral nervessup
Nervous tissue
the skin and the various accessory structures associated with it (hair,finger nails, sensory receptors, and glands)
Integumentary system
the outer layer of the skin, composed of the stratified squamous epithelium
Epidermis
the inner layer of the skin, thicker than the epidermis; a basement membrane anchors the epidermis to the dermis and separates these two skin layers
Dermis
predominantly adipose tissue; the layer beneath the skin that binds the skin to the underlying organs
Subcutaneous layer (hypodermis)
the older cells harden in this process
keratinization
the bottoms layer in the epidermis that is responsible for constantly renewing epidermal cells
stratum basale
specialized cells in the epidermis that produce melanin
melanocytes
a dark pigment that provides skin color
melanin
the boundary between the epidermis and dermis is uneven because epidermal ridges project inward and conical projections of dermis and these extend into the spaces between the ridges
dermal papillae
where the sweat pores open
epidermal ridges
protective coverings on the ends of the fingers and toes
nails
the whitish, thickened, half-moon-shaped region at the base of a nail plate covering the most actively growing region
lunula
the area of modified epithelium beneath the nail, over which the nail plate slides forward as it grows
nail bed
a tubelike depression in the epidermis where hair develops
hair follicle
the nongrowing portion of a hair that protrudes from the skin, that is, from the follicle
hair shaft
the part of a hair that is embedded in a hair follicle
hair root
a bundle of smooth muscle cells that attach to each hair follicle
Arrector pilli
dark hair pigment
Eumelanin
reddish-yellow pigment
Pheomelanin
specialized epithelial cells associated with hair follicles that create sebum through small ducts into the hair follicles
Sebaceous glands
an oily mixture of fatty material and cellular debris; helps keep the hair and skin soft, pliable, and waterproof
Sebum
exocrine glands that are widespread throughout the skin and consists of a tiny tube that originates as a ball-shaped coil in the deeper dermis or subcutaneous layer
Sweat glands
the most abundant sweat glands that respond throughout life to body temperature elevated by environmental heat or physical exercise
Eccrine glands
sweat gland that becomes active at puberty
apocrine glands
secretes ear wax in the external ear canal
ceruminous glands
female gland that secretes milk
mammary glands
a normal response of a wound and the area surrounding it to become red and painfully swollen from injury or stress
inflammation
covers and protects underlying tissues by blood clotting and tissue fluids drying
scab
newly formed connective tissue if the wound is extensive
scar
the formation of small, rounded masses in large, open wounds during healing
granulations
