Cells, tissues, membranes Flashcards
(34 cards)
prokaryotic cells
simplest cellular organism
single celled
lack nucleus + membrane bound organelles
e.g. bacteria
eukaryotic cells
more complex
contain nucleus + membrane bound organelles
make up most multi-cellular organisms
function of smooth endoplasmic reticulum
synthesizes hormones and lipids
function of golgi apparatus
proteins move to GA where they are bound to organelles and are stored until needed
function of lysosomes
vesicles from GA, enzymes within used to breakdown organelle fragments/larger molecules
function of centrosomes
direct microtubule organization within cell
function of nucleolus
essential for formation of ribosomes, composed of mostly RNA
function of nucleus
hold DNA/genetic info of body
function of mitochondria
provides chemical energy for cell through aerobic cellular respiration
function of ribosomes
hold RNA, synthesize proteins from amino acids
function of rough endoplasmic reticulm
protein synthesis occurs here as RER is studded with ribosomes
function of plasma membrane
regulate input/output of cell, acting as a boundary
function of cytoplasam
help maintain the shape of the cell through chemical reactions
specialized cells - red blood cells
function - to carry oxygen
structure - large SA for O2 to pass through (increasing diffusion)
contains haemoglobin which joins with O2
no nucleus
specialized cells - nerve cells
function - to carry nerve impulses to different parts of the body
structure - long, connections at each end, can carry electrical signals
specialized cells - female reproductive cell (egg cell)
function - to join with male cell and then provide food for the new cell formed
structure - large, contains lots of cytoplasam
specialized cells - male reproductive cell (sperm cell)
function - to reach female cell and join with it
structure - long tail for swimming, head for getting into female cell
types of cell damage
physical - trauma, temp extremes, radiation
biological - bacteria, virus, parasite
chemical- toxins, poisons, foreign substances
metabolic - ischemia, toxic build up, nutritional imbalance, fluid imbalance
cell death - apoptosis
the natural death of cells/programmed cell death
cell death - necrosis
a form of cell injury which results in the premature death of cells in living tissue, often resulting from a lack of blood flow
transport in cells - gaseous exchange
diffusion
passage of molecules from a higher concentration to a lower concentration, down a concentration gradient
transport in cells - osmosis
only water
diffusion of water down its concentration gradient
passive, does not require energy
transport in cells - active transport
requires energy
transport is working up/against a concentration gradient
cellular adaptions - diffusion
rate of diffusion increases with larger SA
structure -> organ -> substance:
nephron -> kidney -> water/ions/glucose
alveolus -> lungs -> oxygen, carbon dioxide
villi -> small intestine -> fatty acids + glycerol into bloodstream