histology

Question 1

what does the plasmalemma do ?

Answer 1

separates the cytosol from the outer environments

Question 2

describe the plasmalemma

Answer 2

bimolecular layer of amphiphatic molecules with hydrophilic heads and hydrophobic fatty acid chains.

Question 3

for the plasmalemma what is on the outer and inner surfaces ?

Answer 3

hydrophilic head

Question 4

what does amphiphatic mean ?

Answer 4

contains both hydrophilic and hydrophobic parts

Question 5

what does the plasmalemma contain (6) ?

Answer 5

integral proteins
transporter proteins
channel proteins
receptors
enzymes
cell attachment proteins

Question 6

what permeability is the plasmalemma?

Answer 6

selectively permeable

Question 7

what does the plamalemma allow through (3) ?

Answer 7

water
oxygen
small hydrophobic molecules

Question 8

what are organelles ?

Answer 8

small intracellular ‘organs’ with specific function and structural organisation

Question 9

what are examples of organelles (6) ?

Answer 9

mitochondria
RER
SER
Golgi apparatus
lysosomes
nucleus

Question 10

what does the cytoskeleton provide ?

Answer 10

structural integrity to the cell

Question 11

what is the cytoskeleton composed of (3) ?

Answer 11

actin protein
intermediate filaments
microtubules

Question 12

how many main intermediate filaments are there ?

Answer 12

6 main proteins

Question 13

what are microtubules composed of ?

Answer 13

2 microtubule proteins

Question 14

why are microfilaments very dynamic ?

Answer 14

actin molecules can assemble into filaments and then disassociate

Question 15

why can intermediate filaments be used in pathology to identify tumour origins ?

Answer 15

as different cells express different intermediate proteins

Question 16

describe microtubules including the 2 things it is composed of

Answer 16

hallow tube
composed of two altering alpha and beta subunits of tubulin

Question 17

where do microtubules originate from ?

Answer 17

centromere

Question 18

what is MAP ?

Answer 18

microtubule associated protein
a stabilising protein

Question 19

what drags organelles and vesicles along microtubules and what way ?

Answer 19

kinesin - towards periphery
dynein - towards the centre (dot)

Question 20

what is continuous with the cistern of the ER ?

Answer 20

the perinucleur cistern

Question 21

what is meant by euchromatin ?

Answer 21

DNA that is more dispersed and is actively undergoing transcription

Question 22

what is meant by heterochromatin ?

Answer 22

DNA that is highly condensed and not undergoing transcription

Question 23

what plays a vital role in protein synthesis ?

Answer 23

RER

Question 24

will the RER have more ribosomes if a cell is more metabolically active ?

Answer 24

yes

Question 25

how does the RER appear different from the SER?

Answer 25

RER is studded with ribosomes

Question 26

what is the role of the SER ?

Answer 26

continues the process of proteins produced in RER vital role in synthesising proteins

Question 27

give an example of a cell that has lots of SER

Answer 27

steroid hormone synthasing cell

Question 28

how does the Golgi apparatus appear ?

Answer 28

series of flattened, membrane bound cisternae

Question 29

what is the role of the Golgi cisternae apparatus ?

Answer 29

function in the modification and packaging of macromolecules

Question 30

how does Golgi cisternae fulfil its role ?

Answer 30

adds sugars, cleaves proteins and sorts macromolecules into vesicles

Question 31

what increases surface area in the mitochondria and what is it formed by ?

Answer 31

cristae - formed be inner membrane

Question 32

where does mitochondrial DNA come from ?

Answer 32

yo mama

Question 33

what prevents diffusion ?

Answer 33

occluding junctions

Question 34

how do cells connect with each other ?

Answer 34

intercellular junctions

Question 35

what provides mechanical stability in skin ?

Answer 35

desmosomes

Question 36

what junction is important in cardiac muscle and why ?

Answer 36

communicating junction - important for spread of electrical excitation

Question 37

what allows selective diffusion of molecules between adjacent cell ?

Answer 37

communicating junction

Question 38

what are the types of epithelium (7) ?

Answer 38

simple squamous simple cuboidal simple columnar stratified squamous stratified cuboidal pseudostrtified columnar transitional

Question 39

what are the types of connective tissue (give examples ) ?

Answer 39

soft - tendons, ligaments, dermis of skin hard - cartilage and bone

Question 40

what is included in extracellular matrix ?

Answer 40

fibres tissue fluis adipose cell osteocytes chondrocytes

Question 41

what are fibroblasts ?

Answer 41

active cells that produce and maintain cellular matrix.

Question 42

what can soft tissue be divided into ?

Answer 42

loose dense regular dense irregular

Question 43

what are spindle shaped cells with cigar shaped nucleus ?

Answer 43

smooth muscle

Question 44

what muscle is voluntary and responsible for conscious control ?

Answer 44

smooth muscle

Question 45

what muscle has more striations ?

Answer 45

skeletal muscle

Question 46

what does nervous tissue consist of and what is the ratio between them ?

Answer 46

neurones and glia (their supporting cells) 1:10 glia outnumber neurons

Question 47

what do astrocytes do ?

Answer 47

support ion transport induce blood brain barrier

Question 48

what do oligodendrocytes do ?

Answer 48

produce myelin in the brain and spinal cord

Question 49

what do microglia do ?

Answer 49

provide immune survellence

Question 50

what do Schwann cells do ?

Answer 50

produce myelin and support axons in the PNS

Question 51

what are the three layer of blood vessels ?

Answer 51

tunia intima (inner layer) tunica media (middle layer) tunica adventitia (outer layer)

Question 52

what is the tunica intima consist ?

Answer 52

simple squamous epithelium supported by basal lamina and thin layer of connective tissue

Question 53

what is the tunica media made of ?

Answer 53

mostly smooth muscle