Looks like no one added any tags here yet for you.
Chemical reactions
new bonds form and old ones break
Forms of energy
potential (stored e.g. calories), kinetic (motion), chemical (bonds)
Metabolism
all the body’s chemical reactions
Law of conservation of energy
energy can be converted but no created/destroyed; energy at start (reactants) = energy at end (products)
Catalyst
lower activation energy to speed up reactions e.g. enzymes
Activation energy
initial energy needed to start reaction and break bonds
Exergonic/exothermic reactions
energy released > energy absorbed
Endergonic/endothermic reactions
energy released < energy absorbed
Coupled reaction
energy released by exergonic reaction fuels endergonic reaction
Anabolism
all the body’s synthesis reactions where ions, atoms, and molecules combine to form large molecules
Catabolism
all the body’s decomposition reactions where large molecules split into ions, atoms, molecules
Inorganic compounds
simple molecules that lack carbon e.g. water (most abundant [55-60%] and important), acids, bases, salts
Organic compounds
contain carbon, hydrogen, and covalent bounds (38-43%)
Carbohydrates
main source of chemical energy, 2-3%, CHO e.g. glycogen, starch, sugars, cellulose
Monosaccharides
simple sugars, 3-7 carbon atoms e.g. glucose (blood sugar), fructose (fruits), galactose (milk sugar), deoxyribose, ribose
Disaccharides
combination of 2 monosaccharides by dehydration synthesis e.g. sucrose = glucose + fructose, lactose = glucose + galactose, maltose = glucose + glucose
Polysaccharides
tens to hundreds of monosaccharides e.g. glycogen (stored carbs in animals), starch (stored carbs in plants and food), cellulose (indigestible fibre, plant cell walls, helps eliminate feces)
Lipids
18-25%, CHO
Fatty acids
make up triglycerides and phospholipids; break down to generate ATP; saturated or unsaturated
Triglycerides
major lipid form in body/food; glycerol backbone and three fatty acids; fats and oils; protect, insulate, and store energy (unlimited)
Phospholipids
major component of cell membranes; 2 fatty acids and glycerol backbone connected to N-containing charged group by phosphate group
Health benefits of omega 3 fatty acids
decrease inflammation, increase muscle protein synthesis, oxygen to heart during exercise, and nerve conduction velocity e.g. polyunsaturated (flax, canola oil, olive oil, seafood), EPA, DHA, ALA
Steroid: Cholesterol
minor component of all animal cell membranes; make up bile salts, vitamin D, and steroid hormones
Steroid: Bile salts
needed to digest and absorb dietary lipids
Steroid: Vitamin D
help regulate calcium level; bone growth and repair
Steroid: Adrenocortical hormones
help regulate metabolism, resistance to stress, and salt and water balance
Steroid: Sex hormones (testosterone, estrogen)
stimulate reproductive functions and sex characteristics
Eicosanoids (prostaglandins, leukotrienes)
modify responses to hormones, blood clotting, inflammation, immunity, stomach acid secretion, airway diameter, lipid breakdown, and smooth muscle contraction
Carotenes
synthesize vitamin A (used to make visual pigments in eye); antioxidants
Vitamin E
promotes wound healing, prevents tissue scarring, contributes to normal structure and function of nervous system; antioxidants
Vitamin K
required for synthesis of blood-clotting proteins
Lipoproteins
transport lipids in blood, carry triglycerides and cholesterol to tissues, remove excess cholesterol from blood
Amino acids
central carbon atom bound to a hydrogen atom, an amino group, an acid group, and a unique side chain (HASA)
Amino acid pool
all available amino acids in the body and tissues
Protein turnover
continuous synthesis and breakdown of protein
Protein
structural, regulate processes, immunity, assist in muscle contraction, transport substances, and serve as enzymes; 1+ polypeptide chains folded into a 3D shape (determines its function).
Polypeptides
10+ amino acids combined
DNA
nucleic acid that represents the inherited genetic code for making proteins in nuclei, regulates most cell activity, self-replicating
RNA
nucleic acid that carries genetic code and assists in making proteins
Nucleotide
pentose sugar, nitrogenous base, phosphate group
Adenosine triphosphate
main energy-storing molecule in the body; energy currency
Cellular respiration
catabolism of carbs, lipids, and proteins; releases energy to attach phosphate to ADP to produce ATP
Anaerobic cellular respiration
in the absence of oxygen, glucose partially breaks down into pyruvic acid; yields 2 ATP
Aerobic cellular respiration
in the presence of oxygen, glucose, lipids and protein completely breaks down into CO2 and H2O; yields 32 ATP
Plasma membrane
flexible, sturdy barrier surrounding the cytoplasm; fluid mosaic model: sea of lipids and different proteins; selectively permeable
Nucleus
consists of the cell’s DNA in chromosome (DNA-protein complex) and genes (hereditary units); double membrane bilayer
Nucleolus
cluster of DNA, RNA, and proteins that produce ribosomes
Chromosomes
condensed DNA and histone protein complex that provides structural support for DNA; where genes are arranged
Gene expression
a gene’s DNA is used as a template through transcription, translation, and protein synthesis
Membrane proteins (RIC ELM)
either integral/transmembrane or peripheral; ion channel, carrier, receptor, linker, enzyme, identity marker
Membrane lipids
phospholipids, glycolipids, cholesterol
Cholesterol
stabilizes membrane and reduces fluidity
Concentration gradient
difference in chemical concentration on either side of the membrane
Electrical gradient
difference in ionic concentration on either side of the membrane
Electrochemical gradient
gradients combine to help move substances across the plasma membrane
Passive process: Simple diffusion
movement of compounds from an area of high to low concentration; does not require energy e.g. Vit E, fatty acids; “downhill”
Passive process: Facilitated diffusion
transmembrane proteins help large polar or charged solutes move through the lipid bilayer
Channel-mediated facilitated diffusion
movement of a solute down its concentration gradient across the lipid bilayer through a membrane channel protein; most are for ions (2K+out, 3Na+ in)
Carrier-mediated facilitated diffusion
movement of a solute down its concentration gradient across the lipid bilayer with the help of a carrier transport protein
Passive process: Osmosis
net movement of water through a selectively permeable membrane by simple diffusion or aquaporin channels from an area of high to low solvent concentration (low to high solute concentration); does not require energy
Tonicity
how a solution influences the shape of body cells
Active process: Active transport
movement of substances from a low to high concentration; requires energy (ATP) e.g. glucose, amino acids; carrier proteins change shape to pump a substance across a plasma membrane against its concentration gradient; “uphill”
Cytoplasm
cytosol (intracellular fluid 75-90% water, 55% cell volume) and organelles (specialized structures with shapes and functions excl. nucleus)
Cytoskeleton
helps determine the cell shape; aids in movement, absorption, support, attaching cells; microfilament, intermediate filaments, microtubules
Cilia
hairlike projections that extend from the cell’s surface; oar moving through water; moves fluid along surface; sweep away foreign particles that could interfere with proper cell function
Flagella
motile projection of the cell; longer than cilia; move an entire cell e.g. forward motion of sperm
Ribosomes
granules of protein and RNA found in nucleoli, free in the cytosol, and on rough ER; directed to assemble amino acids into proteins by mRNA which specifies the genetic code copied from DNA
Transciption
in the nucleus, genetic info encoded in a strand of DNA is copied onto mRNA to direct protein synthesis
Promoter and terminator
part of DNA where transcription begins and ends
mRNA
directs protein synthesis through codons (segments of 3 nucleotides specific for certain amino acids)
rRNA
joins with ribosomal proteins to make ribosomes
tRNA
binds to amino acid and holds it in place on a ribosome until it’s incorporated into a protein during translation
Translation
in the cytosol, the ribosome reads the mRNA nucleotide sequence to determine the amino acid sequence of the forming protein while tRNA attaches the amino acids
Rough ER
parallel, flattened membranous sacs covered with ribosomes (protein synthesis); continuous with nuclear membrane; creates membrane, cytosolic, organellar, and secretory proteins
Smooth ER
extends from the rough ER; lack ribosomes; involved in synthesis of fatty acids and steroid hormones (testosterone, estrogen), glucose metabolism, and muscle contraction (sarcoplasmic reticulum form)
Golgi complex
forms lysosomes which function via 60 digestive and hydrolytic enzymes and perform autophagy (digest worn-out cells) and autolysis (destroy entire cell)
Peroxisomes
contain enzymes that use oxygen to oxidize/break down organic and toxic substances e.g. alcohol (similar to lysosome)
Proteasomes
barrel-shaped structures that destroy unneeded, damaged, or faulty proteins by cutting long proteins into smaller peptides that proteases can break down into individual amino acids; they are recycled into functional, healthy proteins
Mitochondria
site of ATP synthesis by enzymes on cristae from energy extracted from carbs, lipids, proteins, alcohol; contain ribosomes and a small circular DNA molecule (mtDNA)
Telomeres
repetitive DNA sequences at the ends of human chromosomes; regulate how many times a cell divides; shorten each time DNA replicates
Cancer
abnormal and uncontrolled multiplication of cells; may spread to other parts of the body via the bloodstream or lymphatic system
Tumour
mass of tissue that serves no physiological purpose; benign (enclosed in a membrane that prevents penetration of other tissues) or malignant (invades surrounding tissues)
Metastasis
spread of cancer; primary tumour attaches to a blood vessel or lymph node; once cancer cells are attached, they pass through the lining of the vessel move into the circulation system, spread to other parts of the body, colonize other organs
Carcinomas
starts in epithelium (cover body surface or line internal organs); most common: skin (melanoma), breast, uterus, prostate, lungs, GI, etc.
Sarcoma
starts in supporting or connective tissues e.g. bones, muscle, blood vessels
Leukemia
starts in blood-forming tissues/cells e.g. bone marrow, lymph nodes, spleen
Lymphoma
starts in cells of the lymph nodes; victims are susceptible to infection (antigens, foreign particles)
Tissue
group of cells with a common embryonic origin and function that carry out specialized activities together
Cell junctions
points of contact between the plasma membrane of cells where cells are held to form tissues
Tight junctions
transmembrane proteins that seal off passageways between adjacent cells (bladder, stomach)
Adhering junctions
contain plaque that attaches to microfilaments and membrane proteins; join cells by cadherins (glycoproteins); help resist cell separation during muscle activity (food passing GI tract)
Plaque
dense protein layer in plasma membrane
Desmosomes
contain plaque that attaches to membrane proteins containing keratin; involved in skin structure and cardia muscle; prevent cells from spreading (epidermis of skin)
Hemidesmosomes
anchor cells to basement membrane (link epithelium to connective tissue; assists in healing and regenerating tissue; involved in satellite cell activity in sections of muscle)
Gap junctions
tiny fluid-filled openings that connect nearby cells; allows molecules to pass from one cell to the other; communication mechanism between cells
Epithelial tissue
densely packed cells arranged in sheets; no spaces between plasma membranes; avascular; nerve supply; protects, secretes, absorbs and excretes; many cell junctions; attach to basement membrane
Surface epithelial tissue
forms skin and some organs, inner lining of blood vessels, ducts, body cavities
Glandular epithelial tissue
makes up portions of gland
Simple epithelium
one layer; involved in osmosis and diffusion
Pseudostratified epithelium
appear to have multiple layers; involved in absorption