A & P - Cells, Tissues & Organs, Homeostasis & Water balance Flashcards
name some features of a prokaryote
non nucleus bacteria DNA in cytoplasm few organelles cell wall
name some features of a eukaryote
nucleus animal, plant or fungi DNA in nucleus many organelles no cell wall (animals)
what is the plasma membrane made of?
phospholipid bilayer - semi permeable
what is the purpose of the plasma membrane?
control flow of substances in/out of cell - maintaining cell homeostasis (gate keeper)
what does cytoplasm contain?
enzymes
products of digestion
waste
where can cytoplasm be found?
in space between organelles
name the types of endoplasmic reticulum
rough
smooth
which endoplasmic reticulum has ribosomes on the surface?
rough
what is the function of rough endoplasmic reticulum?
synthesise proteins (component production)
what is the function of smooth endoplasmic reticulum?
synthesise lipids and steroid hormones (component production)
what is the function of the Golgi apparatus?
protein packaging (assembly & packaging)
in the Golgi apparatus what happens to the proteins when they are packaged?
become vesicles then secretory granules which release hormones
what is the function of mitochondria?
synthesise ATP (energy production)
what type of respiration are mitochondria needed for?
aerobic cell respiration
what is the function of lysosomes?
breakdown foodstuff/waste
destroy proteins/chemicals (recycling centre)
where are lysosomes formed?
Golgi apparatus
how does the structure of the plasma membrane allow it to carry out its function?
protein channels - allow non-lipid soluble substances through
lipid soluble substances can pass unhindered
what is the structure of epithelial tissue?
cells closely packed
attached to basement membrane
what is the function of epithelial tissue?
protects/provide barrier
secretion
absorption
where is epithelial tissue located?
covers body
lining of cavities, hollow organs & tubes
name three types of epithelial tissue and an example of its location in the body
squamous - blood vessels
cuboidal - kidney tubules
columnar - stomach lining
what is a single layer of epithelial tissue called?
simple
what is two or more layers of epithelial tissue called?
stratified
what is the function of simple squamous epithelium and where is it located in the body?
gas/nutrient exchange
blood vessels and alveoli
what is the function of stratified squamous epithelium and where is it located in the body?
protection/barrier
oral cavity, anus, vagina
what is the function of simple columnar epithelium and where is it located in the body?
secretion/absorption
gall bladder and GI tract
what is the function of modified simple columnar epithelium and where is it located in the body?
secretion/absorption
adapted with microvilli
small intestine
what is the function of complex columnar epithelium and where is it located in the body?
muscillary escalator - have cilla and goblet cells
trachea and large airway
name 4 types of connective tissue
bone and cartilage
ligaments
adipocytes
blood
describe the function of connective tissue
support
inflammatory response
connects, anchors
transport, insulation
name some cells which support connective tissue
cologne
fibroblasts
structural/metabolic support provided
name two types of soft connective tissue and their locations in the body
areolar (loose) - membranes around blood vessel, organs, muscle, under skin
adipose - around organs and joints
name two types of hard connective tissue and their locations in the body
cartilage - at joints
bone - skeleton
name 4 types of connective tissue
soft
hard
fibrous
liquid
name a type of fibrous connective tissue and describe it
collagen - very dense. long fibres - gives strength and flexiblity
name two types of liquid connective tissue and their locations in the body
blood
lymph- both around body
name the components of the extracellular matrix of connective tissue
ground substance - fluid
fibre
cells
what is homeostasis?
tendency towards stability of internal environment of healthy organism
what is the function of sensor receptors?
continually feedback information
In homeostatic terms what is a variable?
factor/event being regulated
In homeostatic terms what is the set point?
range in which variable needs to be kept
what is positive feedback and give an example?
self amplifying cycle
blood clotting and childbirth
what does negative feedback do?
decreases effect of original stimulus
name 5 physiological variables which rely on homeostasis?
temp pH glucose blood pressure/volume oxygen
during thermoregulation where are impulses from the skin and brain receptors processed?
hypothalamus
which receptors detect changes in blood pressure?
baroreceptors
during homeostatic regulation of blood pressure where are impulses from the baroreceptors processed?
medulla oblongata
what is negative feedback?
the opposite effect on the variable
can the ‘set point’ of variables change throughout the day?
yes
name some causes of dehydration
diarrhoea faulty thirst mechanism low water intake excess sweating vomiting
what is the total amount of water in the body?
32-40litres
what % of the body is water?
60%
list some reasons why water is important in the body
universal solvent chemical reaction occur in water major component of cells & plasma lubricates joints & organs high ability to retain heat/absorb heat stabilises body temp.
how much intracellular fluid is in the body?
25litres (2/3 or 66%)
how much extracellular fluid is in the body?
interstitial - 12litres
plasma - 3litres
total amount 1/3 or 30%
what is osmosis?
water diffusion from high to low concentration
what are aquaporines?
pores which allow water to move from one compartment to another
what is diffusion?
movement of molecules from high to low concentration
how does temperature affect diffusion?
increased temperature makes particles move faster
how does an increased concentration gradient affect diffusion?
the steeper the gradient the faster diffusion occurs
what is an aqueous solution?
small molecules dissolve
what are electrolytes?
small molecules which carry a charge (+ or -)
(+) cation
(-) anion
what are colloids?
proteins or large molecules as solute
what are suspensions?
larger molecules than colloid - particles settle out
what is osmotic pressure?
pull of solute to move water from high to low concentration
what is a mole?
weight of solute per volume of solution (g/per 100mls)
% of solute per volume of solution
what is osmolatity? (mmol/kg)
osmolar concentration of plasma.
proportional to number of particles per kg of solvent
what is osmolarity? (mmol/l)
osmolar concentration of plasma.
proportional to number of particles per litre of solution
what is a solvent?
the liquid in which a solute dissolves
what is a solute?
the substance that dissolves in a liquid to form a solution
what is a solution?
the mixture formed when a solute has dissolved in a solvent
what does the term iso-osmotic mean?
something has equal osmotic pressure
what does the term tonicity mean?
measure of osmotic pressure against a semi-permeable membrane
what does the term isotonic mean?
equal osmotic pressure
what does the term hypotonic mean?
low osmotic pressure in cell but high outside cell (cause cell to swell)
what does the term hypertonic mean?
high osmotic pressure in the cell and low outside cell (causes shrinking of cell)
which receptors are involved in the thirst mechanism?
baroreceptors and osmoreceptors
what do baroreceptors detect?
changes in blood pressure
what do osmoreceptors detect?
changes in blood osmolarity
which part of the brain receives messages from the baroreceptors and osmoreceptors?
hypothalamus
what is the term used for over hydration?
hyponatraemia
what is gelofusine, what does it treat and how?
a plasma expander, treats dehydration by replacing lost blood volume temporarily
name two types of fluid therapy that are used to treat dehydration
0.9% saline (isotonic) - 0.9g of saline per 100ml water
5% glucose solution - 5g of glucose per 100ml water
which electrolyte is there more of inside a resting cell?
Potassium (K+)
which electrolytes is there more of outside a resting cell?
sodium (Na+)
Chloride (Cl-)
Calcium (Ca2+)
name the dominant extracelluar ion
sodium
which extracellular ion creates osmotic pressure?
sodium
what is sodium needed for?
nerve conduction
propagation of action potential
what hormones control sodium?
ANP and Aldosterone
what does the steroid hormone ANP (Atrial natriuretic peptide) do?
makes kidneys release salt
what does the steroid hormone Aldosterone do?
makes kidneys reabsorb salt