formative sfm Flashcards
Why do energetically unfavourable reactions proceed?
they are coupled to catabolic reactions
What is a nucleotide composed of?
Base + ribose sugar + phosphate
Which of the following is not found the lipid membrane surrounding eukaryotic cells? carbs cholesterol ion channels receptors ribosomes
Ribosomes
What is the dissociation constant for water?
1x10 -14 (mol/L)2.
The amino acid sequence forms which structure of a protein?
Primary
How does an enzyme increase the rate of spontaneous reaction?
It decreases activation energy
What type of bonds link monomers of carbohydrates together?
Glycosidic bonds
What is the net number of ATP molecules generated following catabolism of 1 mole of glucose to lactate?
2
Ingesting alcohol reduces which one of the following intermediates, particularly in the liver?
NAD+
Which molecule transports electrons between complex II and IV of the electron transport chain?
cytochrome c
What mechanism does ATPase utilise in order to generate ATP?
Binding- change mechanism
Which vitamin is a monosaccharide?
Vitamin C
Excess acetyl Co A from fatty acids gives rise to the formation of what?
ketones
Which amino acid is central to nitrogen entering the body?
Glutamate
Which cycle is important in nitrogen metabolism?
glucose- alanine cycle
The bony skeleton is composed of axial and appendicular elements. Which structure forms part of the appendicular skeleton? calcaneus ribs cervical vertebrae sacrum xiphisternum
Calcaneus (bone on foot)
appendicular- bones of the limbs + clavicle
If a person drinks one litre of water, how will it be distributed across the extracellular and intracellular fluid compartments?
Approximately 1/3 will enter the extracellular fluid and 2/3 will enter the intracellular fluid
If red blood cells were placed in a solution of 30mM urea and 170mM NCl what would happen?
it will shrink
ignore urea as it’s not effective osmole
340 is higher than 300 norm
they shrink lose water to external environment
What is directly responsible for the generation of the resting membrane potential?
The permeability of the resting membrane to K+ (leaky k+ channels)
Which type of membrane potential is self-propagated?
Action potential
What property characterises the end-plate potential?
It is always large enough to evoke an action potential in the muscle
The thick filaments of skeletal muscle are composed of which protein?
Myosin
What mediates the increase in intracellular Ca2+ concentration that triggers contraction of skeletal muscle?
Release of Ca2+ from the sarcoplasmic reticulum
An antagonist at a pharmacological receptor is likely to have what combination of affinity and efficacy?
High affinity and no efficacy
Which of the following is a characteristic of the sympathetic nervous system?
Spinal out flow is thoraco-lumbar
What effect does activation of the parasympathetic system cause?
An increase in gut motility
starts digesting- parasympathetic is rest and digest
energy stores
At the neuromuscular junction, what drug acts by inhibiting acetylcholinesterase?
Neostigmine
What is the physiological significance of co-activation of alpha and gamma motor neurons innervating skeletal muscle?
it ensures that the sensitivity of the muscle spindle is retained
- What are the Golgi tendon organs stimulated by and what reflex does this produce?
Increased tension which causes relaxation of the muscle
Viral infection would typically cause elevated levels of which blood cell type?
Lymphocytes
