Chapter 3 Flashcards
cytology
study of structure and function of cells. Somatic and sex cells
cell membrane
physical membrane that controls what goes in and out of the cell, sensitive and provides structural support
plasma membrane structure
phospholipid bi-layer where you have polar hydrophilic heads and non polor hydrophobic tails on the inside very selective keeping inside and outside different.
membrane proteins
peripheral and integral
peripheral proteins
attached to inner or outer surface of the membrane
integral proteins
function as anchors, regocginition, enzymes, receptors, carrier proteins, channels, electron transfer proteins
membrane carbohydrates
lubricate, protect, anchor recpetors, recognize
membrane transport
acitive- energy and passive no energy
diffusion
passive involves distance, size, temperature, and movement direction depend on concentration
simple diffusion
non polar lipids solutes hydrophobic diffuse directly through the membrane
facilitated diffusion
passive large or charged molecules that are unable to pass through the plasma membrane unaided, involves movement through channels or movement facilitated by a membrane carrier
osmosis
diffusion of water. always go to where you have a higher solute concentration
isotonic
same concentration in and out of the cell
hypotonic
lower solute concentration, dilute solution, water flows into the cell,cell starts to swell
hypertonic
higher solute concentration, cell shrinks, water flows out of the cell
filitration
passive depends on size of pores and pressure
facilitated carrier mediated transport
carrier proteins transporting solutes
active transport carrier mediated transport
uses energy and carry proteins, very important in transport ions
vesicular transport
substances move in and out of the cell in vessicles
endocytosis
important in to the cell Example- Iron Viruses, Insulin
receptor-mediated
forme at the membrane
pinocytosis
vessels are filled with extracellular fluid
phagocystosis
vessels containing solids
exocytosis
going out of the cell. vessels inside the that move fluids and solids outside of the cells
cytoplasm
anything outside the nuclear envelope inside membrane outside nucleus
cytosol
intracelluar, inside the cell potassium low sodium has water high number of proteins lipids low carbs
nonmembranous organelles
cytoskeleton, microfilaments, intermediate, intermediate filaments, thick filaments, microtubules
cytoskelton
internal protein frame work strength and flexibility
microfilaments
proteins strands mostly actin involved in motility. movements found in muscle phagel site (white blood cell eating bacteria)
intermediate filiaments
provide support to maintain the shape of the cell
thick fillaments
mostly bundled myosin protein subunits found in muscle cell and helpt to produce contractions
microtubles
found in all cells has a protein called tubulin which forms primary components of the cytoskelton gives strength and helps anchor organelles. Forms the spindle during mitosis
microvilli
increase the cells surface area
centrioles
microtubles found in groups of 3 forming the spindle apparatus
cetromsomes
cells center near the nucleus surronding the centrioles organizes the spindle
cilia
9 pairs of micro tubulars short helps move material over surface
flagella
large than cilia example tail of sperm movement
ribosomes
assemble amino acids into proteins two subunits. light and heavy. Free (throughout cytoplasma) and Fixed (attached to the ER)
mitochondria
power house kidney shaped double membrane organelle produces ATP from carbs especially glucose
endoplasmic reticulum
intracellular membrane connected to the nucleus smooth and rough
smooth ER
synthesis of lipids, steroid, hormones glycerides and glycogen. detoxification of drugs and toxins, storage of calcium and large molecules
rough ER
makes proteins outer surface has ribosomes where proteins are synthesised and moves to the golgi apparatus and vesicles
golgi apparatus
flattened disc called sacuals close to ER and nucleus. synthesis and package secretion for exocytosis and cyotsoles
lysosomes
vesicles from golgi apparatus that contain enzymes and break down food debris bacteria and bone for release a calcium
peroxisomes
smaller than lysosomes carry different enzymes most abundant in the liver to detoxify toxin and oxygize of free radicals
3 cells types of cells junctions
tight gap desmosomes
tight junctions
adjacent integral proteins fuzzed prevents fluids and most molecules from moving between the cells including water
gap junctions
channel proteins forming pores (connexoxex) small molecule through
desesomes
rivets that anchor the cells together where the cell is thicker on the plasma membrane acts cellular cement prevents cells from pulling apart when stressed Example cardiac muscles
nucleus
control center largest organelle has a nuclear envelope phoso lipid double membrane barrier separated by a peri nuclear space
nuclear envelope
nucleoplasm (fluid content of your nucleus) and has a nuclear matrix
chromosome structure
DNA, nucleoli and genetic code
DNA
contains hereditary information DNA is in the chromosome. wrapped around proteins called histones forming a complex known as a nucleosome and when not dividing DNA is in thread like strands called chromatin they condense into bar like bodies call chromosomes when the start to divide
nucleoli
has one or two dark stain nuclear organelles contains DNA coding for synthesizing ribosomal RNA
genetic code
triplet which is three bases each gene contains all the triplets to produce a certain protein
Protein synthesis 2 steps
transcription and translation
transcription 3 phases
initiation, elongation and termination
transcription initiation
DNA strands unwind and content is exposed
transciption elongation
RNA polymerase travels along the strand moving triplet to triplet making a messenger RNA strand. each triplet on the DNA corresponds to a codon on the messenger RNA 45 different types
transcription termination
at a stop sign transcription ends messenger RNA is edited to get rid of Introns and enters the cytoplasm
translation
happens in the cytoplasm requires atp proteins and enzymes
messenger RNA
bonds to light ribosomal subunits and scan for the start codon
polyribosomes
a series of ribosomes attached to the same strand of messenger RNA producing many polypeptide molecules in a short time
