1.
Active transport: The process of substances passing through the cell membrane which REQUIRE energy (ATP) expenditure
2.
amoeboid motion: Cell movement achieved by a cell being able to change shape
3.
anaphase: The third phase of mitosis when chromatids separate and migrate to poles.
4.
anuclear: A cell having no nucleus, eg, mature red blood cells
5.
Basal bodies: Centrioles forming the bases of cilia and flagella
6.
bulk transport: The process by which large particles and macromolecules are transported through plasma membranes. Inc. exocytosis and endocytosis
7.
centrioles: Small cylindrical bodies formed by an array of nine triplet microtubules, which are involved in cell division
8.
centrosome: The centrioles and surrounding protein material involved in forming a mitotic spindle during cell division
9.
chromatid: One of two identical copies of DNA making up a replicated chromosome
10.
chromatin: Unravelled strands of double helical DNA and histone proteins
11.
cilia: Tiny, hairlike projections on cell surfaces that move in a wavelike manner
12.
clathrin coated pit: An invaginated section of plasma membrane coated in protein which binds to and engulfs specific large substances by the process of receptor-mediated endocytosis
13.
codon: Three nucleotides of mRNA which code for one amino acid
14.
Connexons: Transmembrane proteins forming the channels of gap junctions
15.
Crenation: When cells shrivel up due to dehydration
16.
cristae: Invaginations of the inner membrane of mitochondria
17.
cytokinesis: The forming of two daughter cells after mitotic phase of cell cycle when the cytoplasm divides
18.
cytoplasm: The cellular material enclosed by the plasma membrane and surrounding the nucleus
19.
cytoskeleton: Proteinacous cellular scaffolding of microfilaments which provide the cell with structure and shape
20.
cytosol: The fluid portion of the cytoplasm
21.
Desmosomes: Areas on adjacent cell membranes held together by intercellular filaments
22.
Diffusion: The tendency of a molecule or ion to scatter itself evenly throughout its environment
23.
DNA deoxyribonucleic acid: A nucleic acid found in all living cells which carry the organisms hereditary information
24.
electrochemical gradient: A variation based on both a difference in charge and in chemical concentration
25.
endocytosis: Means by which large or large amounts of substances ENTER cells eg. phagocytosis, pinocytosis, receptor-mediated endocytosis
26.
endoplasmic reticulum: Membranous network of tubular channels in the cytoplasm of a cell where proteins and other cell molecules are produced - has rough and smooth varieties
27.
exocytosis: Mechanism by which substances are moved from the cell interior to the extracellular space
28.
Extracellular fluid: Body fluid which is not inside body cells
29.
Facilitated diffusion: The movement of molecules across a membrane ASSISTED by carrier proteins down their concentration gradients without energy expenditure
30.
filtrate: Fluid and solutes that have been passed through a filtration mechanism
31.
Filtration: Fluid and solutes being forced from one compartment to another through a membrane via hydrostatic pressure
32.
fission: The splitting of a cell into two daughter cells
33.
flagella: Long, whip-like extensions of the plasma membrane which propel the sperm cell
34.
Gap Junctions: Protein (connexons) which span the plasma membranes of two adjacent cells forming a channel through which molecules can pass
35.
gene: The part of the DNA which encodes for one polypeptide
36.
Generalised/composite cell: A representation of a cell that includes all of the common features found in many human cells
37.
Glycocalyx: Sugar molecules coating the external cell membrane
38.
Glycolipids: Lipids with sugar groups attached
39.
Golgi apparatus: Flat membranous sacs where cell products are packaged for transport.
40.
histones: Proteins on which strands of DNA wind around
41.
Hydrophilic: Water loving
42.
Hydrophobic: Water fearing
43.
Hydrostatic pressure: The force exerted by a fluid in a system
44.
Hypertonic solution: A solution with concentrations of solutes HIGHER than than found in cells
45.
Hypotonic solution: A solution with concentrations of solutes LOWER than that found in cells
46.
inclusions: Non-functioning units present in the cytoplasm eg. chemical substances and vesicles
47.
Integral proteins: Proteins which are firmly inserted in the lipid bilayer
48.
intermediate filaments: Structural protein filaments larger than microfilaments and smaller than microtubules eg. keratin and desmosome filaments
49.
interphase: The phase in the cell cycle in which the cell is not actively dividing, but is carrying on routine metabolic activities
50.
Interstitial fluid: The fluid which surrounds cells in the tissues
51.
Isotonic solution: A solution with concentrations of solutes EQUAL to that found in cells
52.
Lysis: Death of a cell by breaking the cell membrane
53.
lysosomes: Vesicles that originate from the Golgi apparatus that contain digestive enzymes
54.
macrophages: Large tissue cells which ingest foreign particles for destruction
55.
matrix: The inner part of mitochondria where oxidative respiration takes place
56.
membrane potential: A difference in charge across a cell membrane
57.
messenger RNA: Long strands of RNA which are antisense to a gene of DNA and which direct protein synthesis
58.
metaphase: the second phase of mitosis when chromosomes line up along equator of cell
59.
microfilaments: Thin, high tensile protein filaments eg. actin
60.
microtubules: Long hollow tubes formed by proteins called tubulins which form centrioles and the inner structure of cilia and flagella
61.
Microvilli: Tiny projections on the free surfaces of some epithelial cells; increase surface area for absorption.
62.
mitochondria: Cytoplasmic organelles responsible for ATP generation for cellular activities
63.
mitosis: The process by which body cells divide
64.
mitotic phase: The phase in the cell cycle in which the cell is actively dividing
65.
mitotic spindle: Assembly of microtubules formed by the centrosomes during mitosis
66.
multinuclear: A cell having more than one nucleus, eg. muscle cells
67.
nuclear membrane: Double lipid bilayer membranes surrounding the nucleus of cells
68.
nucleoli: Areas of nucleus made up of ribosomal RNA and proteins where ribosomes are produced
69.
nucleoplasm: Colloidal fluid of the nucleus containing salts, nutrients and other chemicals
70.
nucleosome: A unit of 8 histone proteins with DNA wound around them
71.
nucleus: The control centre of the cell containing genetic material
72.
Organelles: Small cellular structures that perform specific metabolic functions
73.
Osmolarity: The total concentration of all solute particles in a solution
74.
Osmosis: Movement of a solvent (esp. water) through a membrane from a dilute solution into a more concentrated solution
75.
Osmotic pressure: The force exerted on water by the attracting ability of molecules eg. proteins
76.
Passive transport: The process of substances passing through the cell membrane WITHOUT any energy expenditure eg. simple diffusion
77.
perinuclear cisterna: Fluid filled space between the external and internal layers of the nuclear membrane
78.
Peripheral proteins: Proteins not embedded in the cell membrane but attached to either side of it
79.
peroxisomes: Vesicles that originate from the endoplasmic reticulum that contain oxidative enzymes
80.
phagocytosis: Engulfing of solids by cells - cell eating
81.
pinocytosis: Engulfing of extracellular fluid by cells - cell drinking
82.
Plasma membrane: An outer membrane that encloses cell contents
83.
prophase: The first phase of mitosis when chromosomes form, centrioles migrate to poles and nuclear membrane breaks apart
84.
pseudopod: "false foot"
85.
receptor-mediated endocytosis: The process by which specific large substances can enter cells by a clathrin coated pit
86.
ribosomal RNA: RNA associated with proteins to form ribosome units which assist in protein synthesis
87.
ribosomes: Structures where protein synthesis takes place found in the cytoplasm and also on rough endoplasmic reticulum
88.
RNA ribonucleic acid: A nucleic acid that contains ribose and acts in protein synthesis
89.
rough endoplasmic reticulum: Membranous network of tubular channels studded with ribosomes where proteins are produced
90.
Selectively permeable barrier: A barrier which allows some substances to pass whilst excluding others
91.
Simple diffusion: Unassisted movement of molecules from an area of high concentration to an area of low concentration
92.
smooth endoplasmic reticulum: Smooth membranous network of tubular channels continuous with the rough endoplasmic reticulum where synthesis of lipids and steroids and other processes occur
93.
telophase: The fourth phase of mitosis when nuclear membrane forms around daughter nuclei and chromosomes begin to unravel
94.
Tight Junctions: Cell junctions which prevent molecules from passing through the intercellular space between adjacent cells
95.
Tonicity: The ability of a solution to change the tone or shape of cells by altering their internal water volume
96.
transcription: The process by which a copy of a gene is replicated from DNA to mRNA
97.
transfer RNA: Small molecules of RNA which bind to amino acids and bring them to the messenger RNA during protein synthesis
98.
translation: The process by which a polypeptide is made from mRNA
99.
triplet: The three nucleotides of DNA which code for one amino acid
100.
vacuoles: Vesicles which contain mainly water
