Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Primary Physiology > Cellular Physiology > Flashcards

Cellular Physiology Flashcards

1
Q

Common types of interactions between cells

A

Mechanical
Electrical
Chemical - neurotransmitters, neurohormones, endocrine, paracrine, autocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How might control be exerted on an intracellular function? 5

A

Activation or inhibition of enzymes
Regulation of gene expression
Changes in membrane permeability
Regulation of membrane receptor activity
Changes in membrane potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is cytoplasm

A

Everything outside the nucleus within the cell

Cytosol (water, proteins, electrolytes) and organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Components of cytoskeleton - diameters

A

Microtubules - 25nm
Muscle thick filaments - myosin - 15nm
Intermediate filaments - 10nm
Muscle thin filaments - actin - 5nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the function of the cytoskeleton?

A

Cell structure
Cell movement
Cell shape changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Contents of mitochondria with function

A

To produce ATP
folded inner membrane - cristae - oxidative phosphorylation enzymes
Matrix - citric acid cycle
Maternal DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Function of endoplasmic reticulum

A

Rough - protein synthesis
Smooth - steroid synthesis and detoxification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Ribosome size and makeup, location
Function

A

32nm
65% RNA, 35% protein
On rough er or loose in cytoplasm
Protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Function of centrosome

A

Formation of mitotic spindle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Function of golgi
Name of sides

A

Prepare proteins for secretion by exocytosis
Cis (receives proteins from ER) and trans (produces vesicles to travel to cell membrane)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Classifications of cell junction and function, example

A

Anchoring junction - form cell cell adhesions and allow anchoring of cytoskeleton e.g. desmosome
Occluding junction - seals the extracellular space preventing passage of molecules - eg tight junction
Channel forming junction - allow for passage of small molecules between cells - e.g gap junction
Signal relay junctions - allow communication between cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Function of lysosomes and peroxisomes

A

Lysosomes breakdown and eliminate intracellular debris or exogenous substances
Persoxisomes catalyse anabolic and catabolic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Function of cilia
Composition
Function

A

Move substances across surface of cell
9 pairs of microtubules around a central pair (10 in total)
Molecular motor mechanism causing micro tubules to slide relative to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Functions of cell membrane

A

Regulation of passage of substances maintaining homeostasis
Establishment of concentration gradients
Generation of action potentials
Contain cell contents
Anchor cytoskeleton
Site of intercellular connect
Communication - chemical and electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Term for the polar nature of phospholipids with regards to water sensitivity

A

Amphipathic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the term for the glycoprotein coat attached to membrane proteins across the cell

A

Glycocalyx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Categories of protein in a cell membrane by position

A

Integral vs peripheral
Transmembrane vs monotopic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the cell adhesion molecules

A

Membrane proteins with wide range of functions including adherence to other cells or surfaces and signal transduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What proteins are responsible for adhesion to other cells? Which to the extracellular matrix?

A

Cells - Cadherins
Matrix - integrins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Physiological and pathological processes involving cadherins

A

Morphogenesis
Metastasis
Embryogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Physiological processes associated with integrins

A

Platelet adhesion
Leukocyte mobility
Cell matrix adhesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Subunits of a G protein

A

Alpha beta and gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Activation and deactivation sequence of a G protein

A

Ligand binds to GPCR,
release of GDP from alpha subunit, GTP binds in place,
dissociation of G protein,
Alpha subunit interacts with effector
GTP broken down by intrinsic GTPase,
deactivation of G protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Number of G protein coupled receptor transmembrane domains

A

7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Common GPCRs

A

Adrenoreceptors
Muscarinic ACH receptor
Opioid receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Types of G protein and downstream effect

A

Gs - stimulates adenylyl cyclase increasing cAMP - stimulates PKA (a protein kinase) causing target phosphorylation
Gi - inhibits adenylyl cyclase decreasing cAMP
Gq - stimulates phospholipase C cleaving PIP2 into IP3 (opens Ca channels) and DAG (stimulates protein kinase C causing target phosphorylation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What substances can cross phospholipid bilayer

A

Water, lipid soluble substances, small molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Define diffusion

A

Movement of solute molecules due to random thermal motion with a net movement down concentration gradient (high to low)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Factors that influence diffusion across cell membrane

A

Concentration gradient
Surface area
Membrane thickness
Temperature
Lipid solubility
Molecular weight
Electrical charge of particle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Define osmosis

A

Net movement of water molecules due to diffusion between areas of different concentration
Can consider addition of a solute as diluting the water and reducing its concentration thus water diffuses from a high concentration (low concentration of solute) to low concentration (high concentration of solute)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is osmolarity

A

Concentration of solution. 1 mole/litre = 1 osm/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Define osmotic pressure

A

The pressure required to oppose the net movement of water across a semipermeable membrane between two solutions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the osmolarity of ECF normally?

A

300mOsm/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is tonicity?
What does it depend on?

A

The ability of a solution to cause shrinkage or swelling of a cell placed in it.
ECF and ICF osmolarity
Cell membrane permeability to the solute particles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Types of gated ion channels

A

Stretch (mechanically gated)
Chemical (ligand gated)
Electrical (voltage gated)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What sort of carriers are there for active transport (by substance exchange method)

A

Uniport - carries one specific substance
Symport - transports combination of substances
Antiport - exchanges one substance for another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What occurs with membrane proteins when they facilitate active transport? What is the impact of this on transport speed, what else contributes?

A

They undergo a conformational change - speed is in part determined by how fast they can change. Also how dense the carriers are and how saturated they are.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Features of NaKATPase

A

Primary active transporter
Uses ATP to phosphorylate
Antiporter exchanging 3 Na for 2 K both against concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Define primary and secondary active transport

A

Primary - use of energy directly at carrier proteins
Secondary - uses an ion gradient set up by primary active transport in order to facilitate the transport of another molecule - substance binds at first carrier site, ion binds at a secondary site on the protein, allosteric modulation causes transport of substance whilst ion travels down diffusion gradient.

40
Q

What are the two sorts of secondary active transport

A

Co transport - ion and substance carried in same direction
Counter transport - ion and substance carried in opposite directions

41
Q

What is facilitated diffusion? Difference and implication to normal diffusion?

A

Transport of a substance down concentration gradient via a carrier.
Not a diffusion mechanism - no energy is required but transport kinetics are characteristic of carrier mediated transport
Thus carrier saturation occurs limiting rate.

42
Q

What are exo and Endocytosis

A

Transport of substances by fusion of membrane covered vesicles with cell membrane

43
Q

What surrounds the nucleus
Features

A

Nuclear envelope
Double membrane with nuclear pores that allow passage of specific proteins

44
Q

What is the function of the nucleolus

A

Synthesis of ribosome subunits.

45
Q

Components of a nucleotide

A

Base (Purine/pyramidine)
Sugar (ribose or deoxyribose)
Phosphate group

46
Q

Bases in DNA

A

Adenine
Guanine
Cytosine
Thymine

47
Q

Three types of rna

A

Messenger
Transport
Ribosomal

48
Q

What is the main sort of rna in a cell?

A

Ribosomal - constitutes 2/3rds of ribosome

49
Q

Number of chromosomes in human

A

23 pairs

50
Q

What is chromatin

A

The clumped dna protein complex seen in the nucleus

51
Q

Phases of mitosis

A

Prophase - separation of centrioles and formation of chromosomes from chromatin
Prometaphase - nuclear membrane and nucleolus disitigrates
Metaphase - chromosomes line up on cell equator
Anaphase - chromatids split
Telophase - chromosomes, nuclear membrane and nucleoli reform, cytokinesis begins

52
Q

Which enzyme is instrumental to transcription

A

RNA polymerase

53
Q

Which enzyme is instrumental for Translation

A

Aminoacyl-tRNA synthetase

54
Q

How many tRNAs are bound to mRNA at any one time during translation? What are they doing?

A

2, once carrying the amino acid chain, an adjacent one carrying the next amino acid.

55
Q

What are the regions of DNA? Which are used for protein synthesis?

A

Introns - cut out in post transcription processing of pre-mRNA into mRNA
Exons - used

56
Q

What are transcription factors

A

Controlling factors that influence RNA polymerase binding to certain (one or multiple) genes. Can originate in the cell or external to it.

57
Q

Other than transcription factors how else can protein synthesis rate be controlled

A

At the translation stage
Controlling mRNA breakdown

58
Q

Classifications of first chemical messengers between cells

A

Neurotransmitters
Neuromuscular transmitters
Endocrine agents
Paracrine agents
Autocrine agents

59
Q

Definition of ligand affinity

A

Strength of binding with receptor

60
Q

Definition of ligand competition

A

Ability of different ligands to bind with same receptor

61
Q

Definition of ligand agonist

A

Ability of ligand to trigger cell response

62
Q

Definition of ligand antagonist

A

Ability of ligand to bind to receptor without triggering a response

63
Q

Definition of ligand half life

A

Time take for ligand to be metabolised to half its concentration

64
Q

Consequence of ligand lipid solubility

A

Lipid insoluble ligands active cell surface receptors
Lipid soluble ligands active intracellular or intranuclear receptors

65
Q

Definition of receptor specificity

A

Selectivity of a receptor to a single ligand

66
Q

Definition of receptor saturation

A

Percentage of receptors already occupied by ligand

67
Q

Definition of receptor down regulation and up regulation

A

Decrease / increase in number of receptors available for given ligand

68
Q

Definition of receptor sensitivity
What controls it

A

Responsiveness of a get full to given ligand - dependant on concentration of receptors

69
Q

Definition of receptor supersenstitivity

A

Increased sensitivity of cell due to receptor upregulation

70
Q

What are the two processes that allow ligand binding to receptor with conformational change? Brief desription

A

Allosteric modulation - separate modulator binds away from binding site resulting in conformational change allowing ligand binding
Covalent modulation - phosphorylation of receptor with conformational change allowing ligand binding.

71
Q

Group of proteins responsible for phosphorylation

A

Kinases

72
Q

What ways might a receptor result in signal transduction into the cell?

A

Opening or closing of integral ion channel
Activation of intracellular protein kinase
Activation of G proteins mediating further action

73
Q

How can lipid soluble ligands exert their intracellular effect

A

Complex formation with cytosol receptor which moves to nucleolus and promotes gene expression
Ligand moves directly into nucleus and forms complex with nuclear receptor and promotes gene expression,

74
Q

What is the effect of the second messenger system within a cell on signals strength

A

Acts as a cascade amplyfing the signal

75
Q

What is the effect of caffeine and theophylline on the second messenger system?

A

Inhibit phosphodiesterases reducing breakdown of cAMP and cGMP augmenting the second messenger cascade.

76
Q

What is the approx gradient of extracellular to intracellular calcium concentration? Implication?

A

10^4
Rapidly enters cell when given chance

77
Q

Where is calcium stored intracellular

A

ER

78
Q

How are calcium levels reduced in the cell

A

C H ATPase
NaCa Antiporter
Reuptake into ER

79
Q

Examples of intracellular proteins that calcium can bind to
Other functions when released

A

Calmodulin
Troponin
Calbindin

Synaptic function
Protein synthesis

80
Q

What occurs downstream after binding of calcium to calmodulin

A

Acts as a protein kinase

81
Q

Effect of IP3 production from G proteins

A

Release of calcium from ER

82
Q

Mediator that is activated by Gq receptors causing cleavage of PIP2 to IP3 and DAG

A

Phosphlipase C

83
Q

Effect of DAG

A

Activation of protein kinase C

84
Q

Definition of aging

A

Physiological process involving general changes in body systems (usually decline) distinct from the pathological changes of disease

85
Q

Three theories of aging

A

Wear and tear - natural deterioration as a result of continuous functioning
Adaptive evolution - genetically programmed termination of life in interests of evolutionary selection
Non-adaptive evolution - evolved as optimum balance between limited energy sources available and demands of normal function and repair

86
Q

Cellular mechanisms associated with ageing

A

Accumulation of cells with random mutations
Crosslinking of collagens and proteins by glycosylation
Accumulation of oxidant radicles and lipofuscin granules
Genetic clock determining number of cell reduplications
Pleiotropic genes with good effects in early life and bad in later life

87
Q

Cardiac output and renal blood flow of a 70 year old vs young adult

A

64 and 60%

88
Q

Muscle mass of a 70 year old vs young adult

A

74%

89
Q

Cardiovascular changes in aging

A

Lower cardiac output and reserve
Decreased heart rate
Decreased stroke volume
Decreased LV compliance

90
Q

Respiratory effects of aging

A

Decreased pao2, lung elasticity, compliance, vital capacity
Increased residual volume

91
Q

Gi changes with age

A

Decreased smell and taste
Decreased coordination and swallowing
Decreased gastric and pancreatic secretions
Decreased large bowel motility

92
Q

Endocrine effects with aging

A

Increased norad and vasopressin
Decreased RAAS, carbohydrate tolerance, oestrogen and testosterone

93
Q

Renal changes with ageing

A

Decreased kidney mass, ability to concentrate urine, renal response to vasopressin
Increased prostate mass

94
Q

CNS changes with ageing

A

Decreased brain mass, ACh activity, cerebral blood flow, short term memory
Increased reaction time

95
Q

Immunological change with ageing

A

Decreased cellular and humoral immunity

96
Q

Musculoskeletal changes with ageing

A

Decreased bone and muscle mass

Primary Physiology (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions