Cells and Tissues Flashcards
Cytoplasm
- fills space between membrane and nucleus
- organelles make up much of it
- cytoskeleton–>cell skeleton, provides support and movement
Plasma Membrane
- encloses cytoplasm
- separates from interstitial (tissue) fluid
- formed by phospholipid bilayer
Nucleus
- headquarters, contains DNA, oval or spherical
1) Nuclear Envelope - double-membrane barrier
- selectively permeable
2) Nucleoli
- one or more small, dark-staining, essentially round
- sites where ribosomes assembled
3) Chromatin
- DNA combined with protein
- loose network of bumpy threads throughout nucleus
- coil and condense to form chromosomes
Ribosomes
- sites of protein synthesis
- tiny, ribbed, dark bodies made of proteins
Endoplasmic Reticulum
- circulatory system for cell, moving proteins
- system of fluid-filled tubules
1) Rough ER
- studded with ribosomes
- cell’s membrane factory
2) Smooth ER
- functions in lipid metabolism and detox of drugs and pesticides
- create new cell membrane
Golgi Apparatus
- modify and package proteins based on destination
- fill up, then pinch off to form secretary vesicles
- contents of sac ejected outside of cell or transported within cell
Mitochondria
- oxygen used to break down food
- release energy to form ATP molecules
- ex. muscles
- thread-like or sausage-shaped
Lysosomes
- membranous bags containing digestive enzymes
- function as cell’s demolition site for unusable cell structures
- packaged by Golgi apparatus
Centromere
- microtubule organizing center
- centrioles–>organelles within, form mitotic spindle
Cell Extensions
- microvilli–>finger-like projections
- cilia–>fine, hair-like
- Flagellum–>single projection, ex. tail of sperm
Passive Transport
- without use of energy
- down concentration gradient
- diffusion–>osmosis (of water), dialysis (of water and solutes)
- filtration–>water and solutes pushed by hydrostatic pressure
Active Transport
- uses ATP energy, up concentration gradient
- Ion pumps
- specific to one ion
- uses protein carriers
- ex. Na-K
- Vesicular Transport, don’t actually cross membrane
- Exocytosis (out)
- Endocytosis (in)
- enclose substance in sac
- phagocytosis (solids)
- pinocytosis (liquids and dissolved)
DNA
- double helix with 2 nucleotides
- alternating phosphate and sugar units (uprights)
- pairs of N bases (adenine/thymine, cytosine/guanine) (rungs)
RNA
- messengers and decoders of DNA
- single-stranded
- pairs A/uracil, C/G
Transcription
- info transcribed in nucleus from DNA base sequence into complementary mRNA sequence
- 3 base=codon
Translation
- base sequence translated into AA sequence
- mRNA attaches to ribosome
- tRNA recognizes codon of mRNA and brings correct AA
- continues until chain made, creating protein
Interphase
- growth and prep before cell division
- DNA replication occurs right before division
Prophase
- chromatin condense into chromosomes
- chromatid attach at centromere
- spindle fibers appear
- nucleolus and nuclear envelope disappear
Metaphase
- spindle fibers attach to each chromatid
- chromosomes line up along center
Anaphase
- centromeres move apart and away from center
- cleavage furrow appears
Telophase
- nuclear envelope and both nuclei appear
- process of cell division completed (cytokinesis)
Epithelial Tissue
- simple squamous
- stratified squamous
- simple columnar
- stratified transitional
- pseudo-stratified
- simple cuboidal
Simple Squamous
- single layer of flattened cells
- diffusion of respiratory gases
- ex. alveoli of lungs, lining of blood tissue
Stratified Squamous
- many layers, outermost flattened
- protective
- ex. surface of skin
Simple Columnar
- single layer, tall and narrow cells
- protection, secretion, transport
- lining of stomach, internal respiratory
Stratified Transitional
- many layers of varying shapes
- protection
- ex. urinary bladder
Pseudo-stratified
- single layer, tall cells give stratified appearance
- protection
- ex. lining of trachea
Simple Cuboidal
- single layer, cube cells
- secretion, absorption
- ex. glands, kidney tubules
Connective Tissue
- areolar
- adipose
- fibrous
- bone
- cartilage
- blood
Areolar Connective Tissue
- glue that keeps organs together
- webs of fibers, loose matrix of soft, sticky gel
- some collagen (strong) or elastin (stretchy)
Adipose (fat) Connective Tissue
- cells contain large fat vesicles
- area under skin, padding
- protection, insulation, support, nutrient reserve
Fibrous Connective Tissue
- dense arrangement of collagen fibers
- tendons, ligaments, fascia, scar tissue
- flexible, but strong connection
Bone Connective Tissue
- hard, calcified matrix
- skeleton
- support, protection
Cartilage Connective Tissue
- hard, but flexible gel matrix
- nasal septum, disks between vertebrae, external ear
- flexible support, withstand pressure
Blood Connective Tissue
- liquid matrix with flowing red and white cells
- blood vessels
- transportation
Muscle Tissue
1) Skeletal Muscle
- striated, voluntary
- when contracts, pulls bones and skin–>gross movement
2) Cardiac Muscle
- faintly striated, involuntary
- contracts to act as pump for blood
3) Smooth (visceral) Muscle
- no striations
- single nucleus, spindle-shaped
- walls of hollow organs (stomach, uterus, blood vessels)
- contracts to propel substances (peristalsis)
Nervous Tissue
- for control
- receive and conduct electrochemical impulses
- make up structures of nervous system (brain, spinal cord, nerves)
- supporting cells insulate, support and protect
Cell Body
Axon
-impulse away from cell body
Dendrite
-towards cell body
