Chapter 1: Body Systems Levels of Organization Atoms - smallest particle
Molecules - composed of two or more atoms
Macromolecules - large molecule made up of molecules
Organelles - part of cell that performs specific function
Cells - structural and functional unit of life
Tissue - group of cells performing same function
Organ - group of tissues performing same function
Organ systems - group of organs performing similar functions
Organism - group of body systems working to perform homeostasis

Body Systems (1st Semester) Integumentary - (skin, nails hair) regulates body temperature and sensory reception
Skeletal - (bones, ligaments, cartilage) provides support, muscle attachment, produces blood cells
Muscular - (muscle tissue) provides force to move body parts, source of heat
Nervous - (brain, spinal cord, nerves) detect changes in environment, cell communication

Homeostasis Definition: organism's maintenance of a relatively constant internal state within set of ranges
Temperature - 98.6˚F, Blood Pressure - 120/80, Blood pH - 7.4, Hydration - 60% water
Components:
Sensors and receptors: provide info about environment
Set point: what the value should be
Effectors: bodily responses to alter its conditions depending on environment
Negative feedback: correction of deviation, moves in opposite direction
ex: thermostat set to 68, reaches 68, then shuts off
Positive feedback: amplifies change occurring
ex: childbirth, blood clotting, a sneeze

Chapter 2: Biochemistry Element and Atom Structure Element: chemical substance with only one type of atom
Atom: smallest particle of an element made up of protons, neutrons and electrons

Macromolecules Carbohydrates

Such as sugar, starch, cellulose
Made up of C, H, and O
Provide energy for cell
Supply materials to build cell structures
Stored as energy reserves
MONOMER: monosaccharide - glucose, frutose
DIMER: disaccharides - sucrose, lactose
POLYMERS: polysaccharides - starch, glycogen

Lipids

Made of C, H, and O and sometimes P
Do not dissolve in water
Insulation and primary energy storage
Cell membrane and synthesizing fats and makes gametes
Made up of a glycerol molecule and fatty acid chains
TRIGLYCERIDE: 1 glycerol, 3 fatty acid chains
PHOSPHOLIPID: 1 glycerol, 2 fatty acid chains
STEROID: 4 carbon ring structure - cholesterol, testosterone, estrogen

Protein

Made of C, H, O, N, and S
Structural materials, hormones, energy source
Detect foreign substances, speed up chemical reactions
MONOMER: amino acid
POLYMER: polypeptide chain

Nucleic Acid

Made of C, H, O, N, and P
Genetic source
MONOMER: nucleotide
DNA: deoxyribose with nitrogen bases A, T, G, C
RNA: ribose with nitrogen bases A, U, G, C
ATP: ribose with nitrogen base A and 3 phosphate groups

Chapter 3: Cells Organelles Endoplasmic reticulum:

Smooth: no ribosomes, contains enzymes for lipid synthesis, absorption of fat, metabolism of drugs
Rough: ribosomes, site of protein synthesis, sends items to smooth ER and Golgi for processing

Ribosomes:

Site of protein synthesis
2 types: attached to rough ER or floating/free
Made up of a protein and RNA molecule (the rRNA)

Golgi apparatus:

Stacks of membrane-bound sacs
Takes in proteins, packages and delivers them, repackaged inside of vesicles and shipped

Mitochondria:

Major site of cellular respiration
Contains its own DNA and can reproduce
Made up of inner membrane (cristae) and outer membrane with an inner space (the matrix)
Lots of mitochondria found in muscle cells which use a lot of energy

Lysosomes:

Tiny sacs containing enzymes that break down nutrients, foreign particles and broken organelles

Peroxisomes:

Tiny sacs containing enzymes that catalyze bile acids, detox hydrogen peroxide, breakdown lipids, detox alcohol
Abundant in kidney and liver

Cilia:

Tiny hairs that assist in movement of fluids (like mucus) over tissues

Flagella:

Tail-like extensions that assist in movement (ex: sperm)

Vacuoles:

Membrane-bound sacs formed by cell membrane that fold inward
Stores macromolecules, water, toxins, and pigments

Microtubules and filaments:

Thin strands within cytoplasm which are important part of cytoskeleton
Filaments: made of actin proteins that help provide movement like contraction
Tubules: made of tubulin proteins and are thicker

Nucleus:

Houses genetic material and directs all cell activities
Enclosed by a nuclear membrane made of lipids
Has a nucleolus: small organelle made of RNA to form protein
Has chromatin: loosely coiled fiber of DNA or chromosomes

Cytoplasm:

Contains the organelles and cytoskeleton
Slightly neutral pH and serves to communicate signals

The Cell Membrane Regulates the movement of substances in and out of cell and helps cells stick to other cells to form tissue
It is thin and flexible with pockets and foldings and only allows some molecules in and out (selectively permeable)
STRUCTURE:
Lipid bilayer - two layers of phospholipids with water-hating tails facing inward and water-loving heads outward
Cholesterol - keeps fluid in cold weather
Proteins and carbohydrates - cell communication

Passive Transport (no energy use) DIFUSSION:
- molecules or ions spread to regions from more concentrated to less
- occurs if the membrane allows it or a concentration gradient exists
- example: oxygen and carbon dioxide moving in and out of blood

FACILITATED DIFFUSION:
- molecules or ions spread to regions from more concentrated to less
- occurs if membrane allows it, concentration gradient exists and membrane proteins assist
- example: movement of glucose and amino acids

OSMOSIS:
- WATER molecules spread from more concentrated to less
- occurs if membrane allows water to pass through it and if concentration gradient exists

FILTRATION:
- molecules FORCED from more concentrated to less
- separates solids from water
- relies upon hydrostatic pressure created by weight of water by gravity

Active Transport (use of ATP molecules) Generally:
- uses proteins to assist movement
- moves against concentration gradient
- example: proton pumps, Na/K pumps

ENDOCYTOSIS:
- for molecules TOO LARGE to go through passively
- packaged inside of vesicles to move inward
- phagocytosis: cell eating like bacteria or debris
- pinocytosis: cell drinking like water with dissolves in it
- receptor mediated: moves specific particles in to bind to ligands

EXOCYTOSIS:
- secreted out through use of vesicles

Chapter 4: Cellular Metabolism Reactions ANABOLIC

Build up of larger molecules from smaller ones
Requires energy and usually used for cell growth and repair
example: dehydration synthesis

CATABOLIC

Buildup of larger molecules from smaller ones
Releases energy
example: hydrolysis or digestion

Enzymes Definition: complex molecules (almost always proteins) that speed up chemical reactions
They lower activation energy and are not consumed but only needed in small amounts
Very specific to each chemical reaction

SUBSTRATE:
- chemical on which the enzyme acts
- target of an enzyme reaction

ACTIVE SITE:
- part of the enzyme in which substrate binds
- places strain on chemical bonds to intensify chemical reaction

ENVIRONMENTAL FACTORS:
- temperature: most enzymes become inactive at 113˚F or 45˚C
- radiation: or UV rays can denature them
- chemicals/pH: cause loss of control of balance, messes up specific environment

	Criado por Courtney Merkel mais de 8 anos atrás

Cells, body systems, homeostasis