Exam 1

BIO114

3 Domains

Bacteria, Archaea, Eukarya

4 Kingdoms

Protists, Animalia, Fungi, Plantae

Species

smallest unit of classification system. can meet and mate

Isotopes

atoms that have the same atomic number but a different atomic mass (# of neutrons differs)

compound

a substance made from two or more atoms

ionic bonds

occurs between charges particles which donate or take on electrons

Covalent bonds

formed by neutral atoms that share electrons

Polar molecules

results from unequal sharing of electrons between two atoms. Water is polar.

Hydrogen bonds

Occurs between a hydrogen and negatively charged atom. Weakest bond. structure of water.

Acids

substances that release hydrogen atoms

Bases

substances that take up hydrogen atoms

pH

a measure of hydrogen ion concentration. 7 is neutral. <7 is acidic. >7 is basic

Buffers

keep pH within narrow limits in the body. carbonic acid.

Organic compounds

consist mainly of carbon atoms

Dehydration reaction

builds complex molecules (polymers) from smaller units (monomers) by removing water

Hydrolysis

breaks down complex polymers into monomers by adding water

carbohydrates

made of monosaccharides: 6 carbon monomers.

Polysaccharides (complex carbohydrate)

made of many carbon rings

Glycogen (complex carbohydrate)

the storage form in animals

Starch (complex carbohydrate)

storage form in plants

Lipids

found in cell membranes (phospholipids)

Fats

animal origin. solid at room temp.

oils

plant origin. liquid at room temp.

Phospholipid

polar head, nonpolar tails. key component of cell membrane

Steroids

derived from cholesterol. four fused carbon ring structure

ATP

universal energy currency

Light microscopy

low contrast, background is bright

Fluorescence Microscopy

High contrast, can see much smaller particles

Transmission electron microscopy

high-resolution imaging technique that passes a high-energy electron beam through an ultra-thin sample

Scanning electron microscopy

scans a focused beam of electrons across a sample's surface. typically need to metal coat specimens

Facilitated Diffusion

transport of molecules across plasma membrane from higher to lower concentration via a protein carrier

Active transport

movement of molecules from a lower to higher concentration using ATP as energy; requires a protein carrier

Endocytosis (active transport)

brings substances into the cell

Phagocytosis (endo)

Creates a large vacuole to ingest large, solid particles

Pinocytosis (endo)

creates small vesicles to absorb nutrient-rich fluid

Receptor-mediated endocytosis

Highly specific uptake of target molecules (ligands

Exocytosis (active transport)

releases substances from the cell

Osmosis

movement of water from lower to higher solute concentration

Hypotonic

lower solute concentration than in cell. cells tend to swell

Hypertonic

Higher solute concentration than in cell. Cells tend to shrink

Isotonic

Solute concentration the same as cell. cells neither shrink nor swell

Actin filaments

responsible for movement and shape changes due to polymerization/depolymerization. Thin and flexible and near the cell membrane

Microtubules

responsible for transport and organization. big and rigid, protein: tubulin, near nucleus. Involved in mitosis.

Intermediate filaments

strong and durable, spread throughout the cell. strictly structural role. “safety-rope”

Cilia

short and numerous. move fluid across cell surfaces

Flagella

long and usually one. Move the entire cell acting like a propellor (e.x sperm)

Transcription

DNA → RNA. occurs in nucleus

Translation

RNA → protein. Occurs in ribosome

Protein Synthesis

Starts in Rough Endoplasmic Reticulum. Proteins become glycoproteins after adding carbohydrate. They move through Golgi Apparatus and are packaged in secretory vesicles to be exocytosed.

Cellular Respiration

the conversion of glucose to CO2 + H2O + ATP

Aerobic Cellular Respiration

Glycolysis in cytoplasm. Krebs Cycle in mitochondrial matrix. Electron Transport Chain in cristae of mitochondria. Oxygen is final “electron acceptor”

Glycolysis

Cytoplasm. -2 ATP + 1 NADH

Krebs Cycle

mitochondrial matrix. 2 ATP + 1 NADH

Electron transport chain

mitochondrial matrix. 32 ATP’s

Anaerobic Cellular Metabolism

ATP generated through fermentation. NADH → NAD. Pyruvate → Lactate.

Endo-symbionic Theory

Eukaryotes evolved from endosymbionic bacteria. Evidence: mitochondria have their own DNA.

Tissues

groups of specialized cells that are similar in structure and perform a common function

Epithelial Tissue

sheets of cells that line body cavities, cover surfaces, protect underlying tissues

Glands

epithelial tissues specialized to synthesize and secrete a product

Exocrine glands

secrete products into hollow organs or ducts (saliva)

Endocrine glands

secrete products (hormones) into the blood for distribution

Squamous (epithelial tissue)

Flattened, squashed cells. Forms outer surface of the skin. Line blood vessels, lungs, mouth, throat, vagina.

Cuboidal (epithelial tissue)

Cube-shaped cells. Form lining of kidney tubules, glandular tissue

Columnar (epithelial tissue)

Column-shaped cells. Line digestive tract, certain reproductive organs, larynx.

Basement membrane

Noncellular layer directly beneath epithelial tissue. Composed of proteins secreted by epithelial cells and connective tissue. Provides structural support. Attaches epithelial layer to underlying connective tissue

Tight Junctions

Creates an impermeable junction that prevents the exchange of materials between cells. Found in digestive tract where they prevent digestive enzymes from entering the blood.

Adhesion junctions

Holds cells together despite stretching. Found in tissues that are often stretched.

Gap junctions

Allows cells to communicate and small molecules to pass through. Found in excitable tissue such as heart and smooth muscle

Desmosomes

Anchor cells together via intermediate filaments, giving tissues resistance to mechanical stress

Connective Tissue

Supports softer organs of body, connect parts of body, store fat, produce blood cells. Consists mostly of nonliving extracellular materials. Two types: Fibrous, Specialized.

Loose (fibrous connective tissue)

surrounds internal organs, muscles, and blood vessels. Collagen and elastic fibers

Dense (fibrous connective tissues)

Forms tendons, ligaments, cartilage, deeper layers of skin. Many collagen fibers in parallel arrangement.

Elastic (fibrous connective tissue)

Surrounds hollow organs (stomach and bladder). Many elastic fibers.

Reticular (fibrous connective tissue)

Makes up internal framework of soft organs (liver) and the lymphatic system

Collagen fibers

strong, slightly flexible

Elastic fibers

thinner, can stretch

Reticular fibers

thin, interconnected fibers of collagen which provide internal structural framework for soft organs

Cartilage (specialized connective tissue)

transitional tissue from which bone develops. Made of collagen fibers. Maintains shape of certain body parts, cushions vertebrae, lines joint cavities. No blood vessels within.

Adipose tissue

Fat cells. Functions in insulation, protection, and energy storage

Chondroblasts

cells that make collagen

Bones

Contains few living cells. Composed of calcium phosphate. Contains blood vessels.

Platelets

function in blood clotting

Muscle Tissue

Contract to produce movement

Dendrites

cytoplasmic extensions from cell body, receive signals from other neurons

Glial cells

surround and protect neurons. Provide nutrients to neurons

Organs

structures composed of two or more tissue types joined together; perform specific functions

Mucous Membranes

line the digestive, respiratory, urinary, and reproductive tracts

Serous Membranes

line body cavities closed off to the exterior of the body

Synovial Membranes

line joint cavities and produce fluid within the joint

Cutaneous Membranes

Otherwise known as skin

Integumentary system

skin, hair, nails, glands

Skin

an organ which protects from dehydration and makes a form of vitamin D

Epidermis

Outer layer of skin. Multiple layers of stratified squamous epithelial cells. No blood vessels

Keratinocytes

provide a tough waterproof protein

Melanocytes

contain dark pigment (melanin), which protects against UV radiation

Dermis

Inner part of skin. Primarily dense connective tissue (collagen, elastic, reticular fibers). Have blood vessels and sensory nerve endings.

Interstitial fluid

Clear fluid that fills the space between cells which is a source of nutrients and repository for waste

Negative Feedback Control System

deviations from normal are detected and counteracted

Homeostasis (hot temperature)

Sensors in skin and internal organs → Control center (hypothalamus) → Sweating + dilation of blood vessels

Positive Feedback

Process of childbirth