WEEK 1 Flashcards
What bonds are stronger - ionic or covalent?
Covalent
What is the main role of sugars?
They are a source of energy for cells
What are carbohydrates?
Sugars which can be joined together
What is an important component of cel membranes?
Fatty acids
What are steroids?
4 fused carbon rings with functional groups attached
What are the uses of amino acids?
- Sources of energy
- Neurotransmitters e.g. glutamine
- Precursors for other molecules e.g. glycine precursor for porphyrin ring
What does the 3D structure of biomolecules determine?
The immune response
What is the function of biomolecules determined by?
Composition
Bonds
Structure
What is the (i) pathology (ii) aetiology (iii) pathogenesis?
(i) The classification of disease
(ii) The cause
(iii) The process
How is a death certificate written?
1A - cause of death (Ventricular fibrillation)
1B - secondary cause (MI)
1C - (Hypertension)
2 - other contributing factors (Diabetes mellitus)
What is the role of histopathology?
Diagnosis - what is it
Prognosis - what will happen
Prediction - how it will respond to treatment
What are the different approaches to studying anatomy? (HINT: there’s 6)
- Systematic - integrates anatomy, physiology, pharmacology etc
- Regional - essential for understanding the effects of widespread disease
- Surface(/living) - fundamental to clinical examination
- Radiological
- Cross sectional - understanding imaging
- Microscopic - histology/pathology
What is the (i) Sagittal plane (ii) Coronal plane (iii) Transverse plane?
(i) Parallel to the median plane, divides the body into L & R parts
(ii) At a right angle to the median plane, cuts the body into ant & post
(iii) Cross section of the body
How does embryonic segmentation and folding relate to adult anatomy?
- SEGMENTATION: from somites & mesoderm
- segmentation retained in relation to the spinal cord, their emerging spinal nerves, dermatomes & myotomes - FOLDING OF TRILAMINAR DISC:
ectoderm = skin & neural tube (that becomes the SC)
mesoderm = CVS, also splits to form cavities
endoderm = GI & reproductive systems
What is meant by visceral & parietal layers of the serous pericardium, plura and peritoneum?
PARIETAL layer = outer layer (against cavity wall)
VISCERAL layer = inner layer (on the organ)
- In between the visceral and parietal layer is fluid which allows the viscus/viscera to move without friction
What are the anatomical features that allow movement and distension of structures in the body? (HINT: there’s 3)
- STRUCTURES invaginate into “balloons” of serous slippery membranes creating a visceral layer on the organ and a parietal layer against the wall of the cavity. The intervening potential space is lubricated by a few mls of serous fluid.
- TENDONS “bury” themselves into synovial tendon sheaths, allowing blood supply & movement in potential space between visceral & parietal
- Layers of FASCIA separates muscles into compartments => potential spaces allowing movement between muscles & passage of nerves & blood vessels
What are bursae?
Sacs of synovium forming potential lubricating spaces between ligaments/tendons & adjacent bone
What is compartment syndrome?
Injury to the muscle within a compartment which can cause swelling & increased pressure that COMPRESSES neurovascular bundles
What makes up the (i) Axial skeleton (ii) Appendicular skeleton?
(i) Skull, vertebrae (sacrum, ribs, sternum included)
ii) Bones of the UL & LL (scapula, clavicle, hip bone included
What are the 4 properties of cells?
- They are microscopic packages that act as independent units
- Originate from preexisting cells - grow & divide
- They have a finite lifetime - they die
- Various internal processes allow them to change/adapt/respond
What do proteins define?
A cells function
What are the 2 different types of cells? Describe their differences.
(1) PROKARYOTES
- no internal membrane
- simplest & smallest = bacteria
- nucleus absent
- only a few microns in size
(2) EUKARYOTES
- have internal membranes
- are more complex, found in plant/human/animals
- 10 microns or more in size
What 3 main systems do eukaryotes belong to?
- Protein expression
- Secretion pathway
- Uptake & degradation
What is protein expression? Describe it in both prokaryotes & eukaryotes.
Starts in cytosol, enables growth & differentiation
- in PROKARYOTES, DNA is packaged but not enclosed by membrane
- in EUKARYOTES, DNA is packaged & enclosed by a nuclear envelope
mRNA passes from the nucleoplasm to the cytoplasm via nuclear pores, these are selective aqueous channels for transport between nucleus & cytosol
mRNA is then decoded & proteins are made on ribosomes
NOTE: many ribosomes remain free during protein translation
Ribosomes are assembled in the nucleolus at amplified ribosome genes
DNA is packaged with proteins called histones, forming what?
CHROMATIN
Euchromatin = where most of the active genes are found & is less dense
Heterochromatin = more dense
What is the function of the secretion pathway?
Vesicles carry “cargo” from the RER to the golgi (where cargo is processed & sorted)
Vesicles bud from the golgi with membrane from the plasma membrane
Different vesicles can bud from golgi containing packaged secretion
What are the functions of the Rough Endoplasmic Reticulum? (HINT: there’s 4)
- Site of membrane synthesis
- Modifies proteins ( adds sugars, trims them)
- Quality control ( monitors correct folding)
- Signals stress (e.g. when secretion is blocked)
What are the functions of the Golgi? (HINT: there’s 3)
- Receives output of RER
- Modifies lipids/proteins
- Sorts & packages cargo into distinct vesicles for export to other organelles
What is the function of the process of uptake & degradation?
UPTAKE: is by endocytosis from cell membrane to lysosomes (= low pH degradative bodies & contain hydrolytic enzymes)
- membrane/cargo is internalised & delivered to endosomes to then be passed to lysosomes for degradation. Some membrane is recycled back to the cell surface
- portions of the cell itself can be walled off & digested in lysosomes (known as autophagy)
What is the uptake by endocytosis of (i) large particles (ii) small particles called?
(i) phagocytosis
(ii) pinocytosis
What are the 2 great steps in Eukaryotic Cell Evolution? Describe them both.
(1) COMPARTMENTALISATION
- internal membrane compartments with a range of specialised functions
- specialised reactions can then be separated, concentrated & optimised
- vesicles transport membranes & cargo between different organelles
(2) MITOCHONDRIA
- produce MOST of the ATP supply & enables cells to grow BIGGER
- they contain their own DNA & reproduce by dividing in 2
- they come from your mothers egg
What is the cytoskeleton the framework for? (HINT: there’s 3)
Positioning
Movement
Strength
Describe (i) microtubules (ii) microfilaments (iii) intermediate filaments. Mentioning the proteins involved.
(i) important for moving & tethering chromosomes in cell division
Proteins = tubulins
(ii) thinner than microtubules, generate a contactile force enabling cells to move & contract
Proteins = actin
(iii) Provide strength & support
Proteins = keratin, lamins
What is the function of the (i) Smooth endoplasmic reticulum (ii) Peroxisomes
(i) involved in lipid, steroid production & detoxification
(ii) break down some fatty acids & synthesise some special lipids
What are the 4 ways in which cells can communicate?
- Hormones - endocrine
- Mediators - paracrine
- Neurotransmitters - neuronal
- Membrane bound signal molecules - contact dependent
What is the function of bone? (HINT: there’s 5)
Protection Support Movement Storage of minerals Blood cell formation
What is the periosteum? What cells are included within this?
Fibrous layer that covers external surfaces
Cells include:
- fibroblasts (synthesise collagen)
- mesenchymal cells (which differentiate into osteoblasts & chondroblasts)
- osteoclasts
Describe (i) Osteoclasts (ii) Osteoblasts (iii) Osteocytes
(i) Form a “sealing zone” on bone. They release H+ & hydrolytic enzymes to dissolve the mineral & breakdown the extracellular matrix. Is regulated by osteoblasts & hormones
(ii) Derievd from osteoprogenitor cells that line the surface of bone. Deposit the organic matrix which causes mineralisation. Some become entombed, maturing into osteocytes
(iii) Most abundant cell in bone. Embedded w/in lacunae & communicate via projections in canaliculi. W/out them = van buchem disease.
Where are trabeculae laid down?
Along lines of stress
What does (i) Calcitonin (ii) Parathyroid hormone do to osteoclast activity? With reference to calcium.
(i) Decreases the activity of osteoclasts, => decreasing bloods calcium levels
(ii) Increases osteoclast activity, releasing calcium into blood
Bone is dynamic & can be remodelled throughout life. What causes its mass & density to (i) INCREASE (ii) DECREASE?
(i) Excessive mechanical stimulus
(ii) non-weight bearing
What is wolff’s law?
That bone adapts to the load under which it is placed
Bone is dynamic & can be remodelled throughout life. What causes its mass & density to (i) INCREASE (ii) DECREASE?
(i) Excessive mechanical stimulus
(ii) non-weight bearing, sex-hormone deficiency, endocrine/nutritional disorder
What is wolff’s law?
That bone adapts to the load under which it is placed
What is the process for healing fractures? How long does it take?
Takes 2-4 weeks for healing
- dependent on severity & position of fractures & age of pt
Callus formation
- OB quickly form woven bone, to bridge the gap
- Woven bone is weak as the collagen fibres are irregular
Lamellar Bone is Laid Down
- collagen organised in regular sheets to give strength & resilience
Remodelling by OC to restore the original bone shape
