the cell chapter 3 Flashcards
cell theory
cells are building blocks of plants and animals; all cells come from division of pre-existing cells; smallest unit that perform all physiological functions; each cell maintains homeostasis
extracellular fluid
a watery medium surrounding the cell (plasma membrane) separates cytoplasm from ECF
cytoplasm
2 parts: cytosol and organelles
functions of plasma (cell) membrane
physical isolation; regulates change in environment; monitors environment; structural support
double layer of phospholipids
hydrophilic and hydrophobic
cholesterol
helps maintain integrity of membrane
cell membrane is permeable or semi?
is semi-permeable
membrane proteins
anchoring, recognition, enzymes, carrier, and channels
recognition protein (identifiers)
labels surrounding cells as normal or abnormal (responds to ligands)
anchoring proteins (stabilizers):
attaches to inside or outside structures and anchors proteins to membrane
integral proteins
proteins that allow things to go IN the cell. transporters for polar substances
peripheral proteins
dont go all the way through, stays on outer or inner layer of bilayer. can be receptors and enzymes
carrier protein
transports specific solutes through membrane
channels
regulate water flow and solute through membrane
what are the 3 membrane carbohydrates and what do they do?
glycoproteins- immunity
glycolipids- maintains stability and facilitate cell to cell interaction
glycocalyx- sugary sticky coat used for protection, lubrication, binding specificity and recognition
tight junctions
prevents leakage between to adjacent cell membranes. common in stomach and intestines epithelial cells
desmosomes
increase surface area by tie two adjacent cells together, resists change=skin
gap junctions
channels where sugar, ions and AAs can pass between cells. in the heart
what is cytosol?
high K, low Na+, high protein inside cell
non-membranous organelles (no membrane contact, contact with cytosol)
cytoskeleton, microvilli, centrioles, cilia, free ribosomes, proteasomes
membranous organelles (covered with cell membrane, isolated from cytosol)
rough ER, smooth ER, golgi, lysosomes, peroxisomes, mitochondria, nucleus, cisternae
cytoskeleton
skeleton of the cell, structural proteins, microtubules, microfillament, and intermediate filament
microtubules
large, tubulin protein, strength and anchor organelle, change cell shape. form mitotic spindles
microfillaments
form microvilli, actin protein, pairs with myosin for muscle movement
intermediate filaments
durable and stabilize cell position
cilia
small hairs that help move fluid across cell surface
microvilli
increase surface area for absorption, attaches to cytoskeleton
ribosomes functions and type
make enzymes, builds polypeptides
free rib- cytoplasm, manufacture proteins FOR CELL
fixed rib- attached to rough ER, manufacture proteins FOR SECRETION
proteasomes
enzymes, proteolysis
cisternae
storage chambers within membranes important for protein and lipid processing, sorting and packaging, detoxification, transport vesicle formation, protein synthesis and folding
smooth ER
no ribs, syntehsizes lips and carbs, lots of calcium
rough ER
covered in ribs, protein and glycoprotein synthesis, protein structures, encloses products in transport vesicles
golgi aparatus
packaging center; vesicles form face and exit face, modifies and packages products for exocytosis, modifies membrane by adds or removes components
lysosomes
carry enzymes to cystosol, cleans up inside cells, breaks large molecules, attacks bacteria, maintains immunity, ejects waste through exocytosis
if something in the cell is too toxic or damaged beyond repair what happens?
lysosomes turn on apoptosis, or lysosomes will break itself down to release digestive enzymes and explode
primary lysosomes are made…
in golgi
secondary lysosomes are…
are fused with damaged particles and activate digestive enzymes
peroxisomes
contains vesicles produced by free ribs, breaks down fatty acids to use for ATP, breaks down hydrogen peroxide by Catalase (liver process)
“somes” and “ase” indicates…
an enzyme
mitochondria
double phospholipid membrane, has its own DNA (the same in everyone!); cristae, matrix and aeorobic metabolism (using O2 to break down food for ATP)
C6H12O6 +O2=> CO2 +H2O +ATP
nucleus
largest organelle
nuclear envelope
double layer membrane around nucelus
perinuclear space
between nucleaur envelope
nucelar pores
tiny communication passages, too small for DNA so RNA uses it to seep out of
what is in the nucleus?
DNA, nuceloplasm, nuclear matrix, nuceloli, synthesizes rRNA and ribsomal subunits
chromatin vs chromostomes vs nucleosome
chromatin- loosely coined DNA, cells DONT divide
chromosome- tightly coiled DNA, cells do divide
nucleosome- DNA coiled around histones
what is genetic code?
chemical language of DNA. 3 DNA bases= 1 amino acid
EVERY PROTEIN HAS GENETIC CODE
steps of protein synthesis from DNA
transcription- DNA to mRNA
translation (tRNA)- ribosomes read mRNA to make AAs
processing ( ribosomal RNA)- rough ER and golgi produce protein
transport types
active- needs energy/ATP
passive- no energy
what can pass in simple diffusion?
lipid solubles, dissolved gases
what passes in faciliatated diffusion?
smaller particles, +charge polar
osmosis
water always follows sugar or salt, uses aquoporins from high conc. to low conc.
tonicity types and %NaCl
RBC has 0.9% NaCl
isotonic
hypotonic
hypertonic
isotonic
same % inside and outside of cell
hypotonic
more solute inside cell, water comes in and cell fills with water til it explodes (hemolysis)
hypertonic
more solute outside of cell, water leaves, cell shrivles (crenation)
carrier mediated transport
sodium potassium pump
3Na+ out of cell, 2K+ into cell
What causes protein to change shape and be able to be used in facilitated transport?
phosphorylation
phagocytosis
phagosomes engulf large objects, cell ingestion of other materials, helps in cleaning
steps of mitosis
interphase (G1, synthesis, G2)
prophase
metaphase
anaphase
telophase
what is the longest stage of interphase?
G1
what cells do not experience mitosis?
neurons and muscle cells
Tumor (neoplasm). brain example
abnormal cell growth and division, mutations. ex: neuroglia that mutated
benign
contained, non life threatening
malignant (metastisis)
not contained, travels from one area through the blood to another area and continues mitosis across different areas
cancer is…
uncontrolled mitosis
how does chemotherapy work?
blocks mitosis of all cells
mitosis vs meiosis
mitosis- diploid (2 haploids)
meiosis- haploid, sperm and egg
homologous chromosomes have how many…
23 pairs, 46 chromosomes
zygote
