A&P I : Chapter #3 Exam Terms

integral proteins

a general group of proteins which span the entire width of the plasma membrane; the most common type

peripheral proteins

a general group of proteins which are attached to either the inner or outer surface of the plasma membrane

anchoring proteins

a protein that attached to either inside or outside structures to stabilize the cell

recognition proteins

a protein which identifies a cell as normal or abnormal; often glycoprotein

enzyme proteins

a protein that catalyzes reactions either inside or outside of the cell; example is found in the GI tract

receptor proteins

a type of protein that binds and responds to ligands

carrier protein

a protein that transports a solute across or through the cell membrane

glycocalyx

composed of proteoglycans, glycoproteins, and glycolipids; functioning as receptors and cell recognition; maintain lubrication, important for anchoring and locomotion

cytoskeleton

a system of structural proteins that give shape and strength to the cell; consist of 3 main groups of structures (actin filament, microtubules, intermediate filament)

microfilaments

smallest of the cytoskeleton proteins; thin filaments composed of actin

intermediate filaments

mid-sized structural proteins; example of collagen, adds strength

microtubules

large hollow tubes made of tubulin; largest of cytoskeleton, acts like a track for vesicle movement form spindle apparatus

microvilli

folds of plasma membrane, increase surface area for absorption

centrioles

organelles which control the formation of spindle apparatus during mitosis, found in centrosome

cilia

small hair-like projections from plasma membrane, move fluids across cell-surface

ribosomes

organelles which are essential to protein synthesis, can be free or attached to ER

proteasome

organelle which contains enzymes that break down proteins for recycling

smooth ER

network of membranes in cell; functions to synthesize lipids and carbohydrates

rough ER

network of membranes in cell, covered with ribosomes; essential for protein synthesis, contionous with outer nuclear envelope

golgi appartus

system of membranes in a stack, responsible for formation of vesicles works to modify and package secretions and repair/modify plasma membrane

lysosome

vesicles that contain powerful enzymes, function to break down damaged organelles or invading microorganisms

perioxisomes

vesicle that contains enzymes that break down organisms. compounds of releasing hydrogen peroxide in the process

mitochondria

organelle which contains outer membrane, cristae, and a matrix responsible for production of ATP

glycolysis

phase involves the chemical reaction which glucose is converted to 2 pyruvic acid molecules, along with production of 2 ATP, and 2 NADH

citric acid cycle

this reaction involves a cyclic reation in which pyruvic acid is converted into CO2, ATP, NADH, and FADH2 are produced

electron transport transport

series of reactions ocurs in the mitochondrial cristae membranes, requires oxygen, many ATP are produced along with H2O

lactic acid

pyruvic acid is converted to this molecule when oxygen is not present in the cell

nucleolus

organelle contained within nucleus, function is to synthesize rRNA and ribosomal subunits

chromatin

loosely coiled DNA, found in nucleus in nondividing cells

chromosomes

tightly coiled DNA, found in nucleus of dividing cells

histones

proteins that attach to DNA

nucleosomes

histones along with DNA coiled around them form these structures

nuclear envelope

double membrane around nucleus

nuclear pores

openings in nuclear envelope which small ions can pass through

nucleoplasm

fluid within nucleus containing ions, nucleotides, some RNA, and enzymes

DNA

nucleic acid which contains genetic code/instructions

gene

instructions in DNA synthesis for one protein

genetic code

chemical langauge of DNA (A,T, C, G)

triplet code

3 nitrogenous bases which code for 1 amino acid

codon

3 nitrogeneous bases on mRNA which bind to DNA triplet coe on template strand

gene activation

uncoiling of DNA in order to start protein synthesis

transcription

synethsis of mRNA from DNA

RNA polymerase

enzyme needed to make mRNA

translation

process in which the mRNA attaches to the ribosome, tRNA bring amino acids to ribosome and polypeptide

protein processing

rough ER folds proteins into 2D or 3D

vesicular transport

movement of materials into or out of cell; bulk transport

endocytosis

a type of active transport that moves substances, including fluids and particles, into a cell

receptor mediated endocytosis

type of endocytosis involving receptors that bind ligand

ligand

special molecule that binds receptor

pinocytosis

small amount of liquid is taken into cell

Phagocytosis

large substances are engulfed

exocytosis

involves ATP

vesicles

small membrane that contains molecules, formed from golgi aparatus

mitosis

a general term for the division of genetic material (DNA in form of chromosomes) equally between two newly formed cells

interphase

the non dividing phase of the cells life cycle

G1 phase

part of interphase, cell grows, organelles duplicate, and protein synthesis begins

S phase

the phase of interphase in which DNA replication and histone synthesis occurs

G2 phase

the phase of interphase in which protein synthesis is completed and centrioles replicate

chromatids

duplicated chromosomes are composed of two of these, bound together by a centromere

prophase, metaphase, anaphase, telophase

4 phases of mitosis

cytokinesis

division of cytoplasm toward end of mitosis

prophase

first phase of mitosis in which the nuclear membrane disappears, centriole pairs move to opposite ends of the cell, spindle fibers form and attach to the kinetochores of the chromosomes

anaphase

phase of mitosis in which chromosomes seperate at the centromere because the microtubulues/spindle fiber pull them apart, moving them to opposite ends of the cell

telophase

the phase of mitosis in which the cleavage furrow deepends, the two newly formed cells are nearly seperated, and the nuclear membrane of each new cell reforms with the result being 2 identical cells

metaphase

the phase of mitosis in which the chromosomes line up in a single line across the equatorial plate of cell