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GEM Year 1 Key Info > Case 1.1 > Flashcards

Case 1.1 Flashcards

1
Q

List the 4 tissue types.

A

Epithelium
Connective tissue
Muscle
Nerve

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2
Q

Describe the composition and functions of epithelium.

A 
Covering/lining membranes, separated by BM, specialised according to function, e.g. protective, holding tissues together, thermoregulation, hormone release, absorption.
Types:
Simple = 1 layer
Stratified = many layers
Squamous = flat
Cuboidal
Columnar
Transitional
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3
Q

Describe the composition and functions of connective tissue.

A

Support, from embyronic mesoderm, 5% cells 95% ECM [collagen, elastin and ground substance]

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4
Q

Describe how cells are adapted to their function by means of membrane specialisations.

A

Cells can be adapted in terms of their components or their membrane specialisations.
Cilia and flagella: beat rhythmically using microtubule core.
Microvilli (& stereocillia): to increase surface area (no active movement)

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5
Q

Explain the structure of the basement membrane and why it is important.

A

Sheets of matrix at interface of functional tissue (parenchyma) and support tissue (stroma).
Composed mainly of type IV collagen, glycoproteins (laminin secreted by epithelial cells, fibronectin from fibroblasts) and GAGs.
Functions:
adhesion,
barrier (permeability),
organisation of cells (controlling growth and differentiation)
Relevant to pathology, especially cancer.

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6
Q

Give examples of the main support cells and common extracellular matrix proteins in connective tissue

A

Contains cells (5%) and the main product of the cells: extracellular matrix (ECM, 95%)
ECM = collagen and elastin fibres + ground substance (polysaccharides - glycosaminoglycans [GAGs]).
Specialised support/transport. Also has an immune function (hosting cells) and includes adipose tissue (metabolic role).
Cells:
Fibroblast: secretes ECM for most tissues: collagen and elastin
Chondrocyte: secretes ECM for cartilage: collagen II
Osteoblast: secretes ECM of bone: collagen I
Myofibroblast:secrete ECM and have contractile function
Adipocyte: storage and metabolism of fat

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7
Q

Why don’t epithelia fall apart/leak?

A

Cell junctions bind the cells together.
Roles:
Structural- to attach cells to each other and to the cytoskeleton: zonula adherens and desmosomes
Anchoring- to attach epithelia to the basement membrane and hence to the tissues beneath: hemidesmosomes
Barrier– preventing the passage of substances between cells: tight junctions
Communication– allowing communication between cells (coordinates heart, muscle etc): gap junctions

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8
Q

Describe the general structure and arrangement of the layers in a tubular organ.

A 
MUCOSA:
Epithelium
Basement membrane
Lamina propria – connective tissue
SUBMUCOSA:
Muscle layers/connective tissue wrapper (adventitia/serosa)
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9
Q

Why don’t epithelia fall apart/leak?

A

Cell junctions bind the cells together.
Roles:
Structural- to attach cells to each other and to the cytoskeleton: zonula adherens and desmosomes
Anchoring- to attach epithelia to the basement membrane and hence to the tissues beneath: hemidesmosomes
Barrier– preventing the passage of substances between cells: tight junctions
Communication– allowing communication between cells (coordinates heart, muscle etc): gap junctions

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10
Q

What are glands?

A

Down-growths of epithelium.
Can be a single cell to an organ. Exocrine = secretion, e.g. breast, liver, pancreas. Organelles reflect type of secretion. Cancer = adenocarcinoma.
Endocrine = secrete directly into the blood e.g. pituitary, thyroid.

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11
Q

What are parenchyma and stroma?

A

Parenchyma: functional cells
Stroma: support cells including connective tissue, blood vessels, nerve

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12
Q

Describe simple squamous epithelial cells. Where are they found?

A

Flattened cells
Thin layer – small intracellular volume
Exchange functions (gases, chemicals)
Alveoli, kidney glomerulus, blood vessels lining & capillaries.

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13
Q

Describe simple cuboidal epithelial cells. Where are they found?

A

Absorption & secretion
Larger intracellular volume = greater contents
Secretory glands (sweat, sebaceous)
Renal tubules

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14
Q

Describe simple columnar epithelial cells. Where are they found?

A

Large intracellular volume
Potential for energy reserves & high organelle density
Motility, absorption & processing

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15
Q

Describe pseudo-stratified epithelial cells. Where are they found?

A

Appear stratified but all cells contact basement membrane
Nuclei at different levels
Found in respiratory tract

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16
Q

Describe stratified squamous epithelial cells. Where are they found?

A

Layers of flattened cells
Areas of wear and tear – abrasion resistance
Oesophagus, vagina, skin (almost)

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17
Q

Describe transitional epithelial cells. Where are they found?

A

Stretchy & waterproof
Bladder & urinary tract
Permits cell distension & return to original shape

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18
Q

On what tissue responses are all diseases based?

A

Cellular adaptation to environmental change (today)
Cell death (when adaptation does not work-later in the module)
Tissue responses to injury and how tissues heal (later this week)
Abnormal cell growth (e.g. cancer –module 2)
Response to environmental stimuli (mechanical, extremes of temperature, radiation, electrical, chemical, nutritional) (throughout)
Immune responses (inadequate, excessive, inappropriate) (Ian Todd)
Genetic factors

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19
Q

What are the different pathogenic classifications for congenital and acquired pathologies?

A

CONGENITAL:
Genetic (inherited/spontaneous)
Non-genetic (environmental/accidental)

ACQUIRED:
Inflammation (acute/chronic)
Growth disorders (neoplastic/non-neoplastic)
Injury and disordered repair (kinetic/chemical)
Haemodynamic (shock/occlusive lesions)
Disordered immunity (immunodeficiency/autoimmune)
Metabolic and degenerative

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20
Q

Outline the different cellular adaptive mechanisms.

A

Hypertrophy (increase in cell size)
Hyperplasia (increase in number of cells)
Atrophy (shrinkage in cell size)
Involution (reduction in number of cells, usually by apoptosis)
Metaplasia (change in cell type)
Neoplasia (permanent, non-adaptive alteration of growth, abnormal proliferation)

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21
Q

Outline the basic composition and functions of blood.

A

Cells suspended in a fluid medium called plasma (cells 35%; plasma 55%)
Vehicle to transport gases, nutrients, cells, hormones, antibodies and metabolites around the body (5-6L altogether)
Has a role in maintaining body temperature
Formed in bone marrow (haematopoiesis)

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22
Q

What is plasma?

A

Fluid containing proteins (8%), salts (1%) and lipid (0.5%)

without blood coagulation proteins = serum

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23
Q

Outline the cellular components of blood.

A
  1. Erythrocytes - RBCs (98%)
    Biconcave disc, anuclear, no organelles, O2 transport, CO2 and H removal.
2. Leukocytes - WBCs (2%)
MYELOID:
Mega-karyocyte = thrombocytes (3.)
RBCs (1.)
Mast cells
Myeloblast =
- Granulocyte: basophil, eosinophil, neutrophil
- Monocyte: Macrophage
LYMPHOID:
NK cell
Small lymphocytes:
- T cells
- B cells (-> plasma)
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24
Q

What is the function of platelets?

A

Adhere to defects in blood vessels and assist in clotting mechanism

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25
Q

What is the function of plasma?

A

Transport gases, nutrients, cells, hormones, antibodies, and metabolites around the body

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26
Q

What are the main functions of WBCs?

A

Generally: destroy infecting organisms and remove dead and damaged tissue.
Basophils = inflammation, histamine and heparin production, phagocytosis
Eosinophils = parasites, allergy
Neutrophils = remove damaged tissue and kill small organisms
Macrophages (monocytes) = destroy invading organisms - phagocytosis
NK cells = engulf foreign cells
T cells = specific immune response
B cells = antibody synthesis

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27
Q

Describe the main blood analyses

A

The fraction of the blood composed of red blood cells: Haematocrit (HCT)

Erythrocyte sedimentation rate (ESR): The rate at which the red blood cells settle to the bottom of the test tube.

Total amount of haemoglobin in the blood(Hb)

Mean cell haemoglobin (MCH-from Hb and RBC)

Mean cell volume (MCV-average volume of a red blood cell)

Mean cell haemoglobin concentration (MCHC-average concentration of Hb in a given volume of packed red blood cells)

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28
Q

What might be cause of high or low RBCs/haematocrit?

A

High = dehydration
Low = anaemia
(low Hb= anaemia/blood loss)

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29
Q

What might result in leukopaenia or leukocytosis?

A

Leukopaenia (low WBC) = bone marrow failure

Leukocytosis (high WBC) = infection and inflammation/leukaemia

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30
Q

How do we pass on genes? How does this link to variation?

A

DNA, histones, chromosomes, gametes, alleles (dominant and recessive), punnet squares (inheritance and variation).

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31
Q

Describe DNA structure

A

A very long polymer of nucleotides (deoxyribose, phosphate group and nitrogen base = AGCT) with phosphodiester bonds.
Basic shape = twisted ladder, double helix, where the rungs are nucleotide pair bonds (nitrogenous bases).
Pyrimidines = thymine and cytosine, one ring of carbon and nitrogen atoms.
Purines = adenine and guanine, two rings of carbon and nitrogen atoms.
AT, CG = Chargraff’s rule.
Attracted by hyrdogen bonds.
Genes are organised into chromosomes, which are stored on histones.

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32
Q

Describe RNA structure.

A 
Single strand, sugar-phosphate backbone = ribose.
Thymine -> Uracil substitution.
mRNA = messenger
tRNA = transfer (for protein synthesis)
rRNA = part of ribosome
miRNA = post-transcriptional regulation.
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33
Q

How are genes expressed (transcription)?

A

Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product (often proteins).
This involves transcription, where the DNA is copied to RNA.
In the nucleus, RNA polymerase (an enzyme) adds nucleotides one by one to form a strand which is complementary to the DNA template strand, creating a copy of the coding strand (except U not T).
This process is initiated by a special DNA sequence called the promoter and a set of DNA-binding proteins—transcription factors.
Addition of new nucleotides begins at the 3’ end of the template or ‘anti-sense’ strand.

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34
Q

Describe the process of mRNA translation.

A

Central Dogma: DNA → RNA → Protein

Every 3 nucleotide pairs are a codon, each codon is one amino acid.

mRNA is converted to tRNA, which has unique anticodons for each amino acid.

Protein +rRNA = ribosomes.

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35
Q

Describe RNA processing.

A

The parts of the mRNA which code for proteins are called exons (cut out = introns). Whether they are exons or introns is signalled by certain sequences.
At the end of processing, RNA is modified by capping (G-cap attached to 5’ end), splicing (removal of introns), and tailing (As added to 3’ end). This protects RNA from degradation and provides recognition sequences.

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36
Q

Why do cells communicate with each other?

A

To respond to immediate environment, central commands, local commands etc., coordinate cellular responses, integrate signals from multiple sources and sometimes to initiate cell death.

37
Q

What are the stages of cell signalling?

A
  1. Reception
    A chemical message binds to a protein on the cell surface
  2. Transduction
    The binding of the signal molecule alters the receptor
    This starts a cascade of reactions
  3. Response
    The transduction pathway triggers a response
    The responses can vary from turning on a gene, activating an enzyme, rearranging the cytoskeleton
38
Q

What are the main types of cell signalling?

A

Chemical (neurotransmitters/hormones)
Physical/mechanical
Junctions

39
Q

What does GPCR stand for?

A

G Protein Coupled Receptors

40
Q

What does GPCR stand for?

A

G Protein Coupled Receptors

G = guanine nucleotide-binding protein

41
Q

What is a GPCR?

A

A single long polypeptide chain folded into a globular shape with portions inside and outside the cell.
Interacts with G proteins in the plasma membrane (alpha, beta and gamma subunits).

42
Q

How do GPCRs work?

A

Binding of a signal on the outside changes the shape of the receptor and activates the G protein to activate local enzymes - adenylyl cyclase and phospholipase C.

43
Q

Outline the types of G proteins and what they activate.

A

Gs: activation of adenylate cyclase and production of cAMP
Gi: inhibition of adenylate cyclase and decreased production of cAMP
Gq: activation of PLC to produce IP3 and DAG (calcium signalling)
s/i/q is the name of the alpha subunit (something called Gαs, Gαi, Gαq

44
Q

Describe the action of an ion channel linked receptor and give examples.

A

The channel opens in response to a chemical, allowing ions to move through and change the electrical properties of the cell.
Important in nerve and muscle cells - ACh receptor, GABA receptor, 5HT3.

45
Q

Describe the action of enzyme linked receptors and give examples

A

Consists of an extracellular ligand binding domain, a single transmembrane helix, a cytoplasmic region containing the protein tyrosine kinase activity.
Activation causes them to come together and autophosphorylate, stimulating signal transduction pathways.
Examples include insulin and growth factor receptors.

46
Q

What is phosphorylation?

A

The addition of a phosphate group to a protein or other organic molecule = turns many protein enzymes on and off. Can be catalysed by kinases.

47
Q

Describe cytoplasmic and nuclear receptors

A

For signals that can cross the cell membrane, e.g. oestrogen, thyroid hormone. Alter gene transcription and therefore protein levels directly.

48
Q

What happens after receptor activation?

A
  1. Receptor activation leads to intracellular signalling cascades and second messenger systems
  2. These lead to changes in cell function
  3. Signals are turned off eg.
    Chemical signals are enzymatically degraded
    G proteins become inactivated by GTPases
  4. Cells return to previous state (unless more signal is around)
49
Q

What are the features and uses of gap junctions?

A

Allow small molecules and ions to pass
Narrow pore (2-4nm) spanned by pore forming proteins called connexins
Provide rapid metabolic and electrical coupling
E.g. cardiac tissue (coordinated action)

50
Q

Describe and give an example of gaseous communication.

A

Gasotransmitters include oxygen, carbon dioxide, NITRIC OXIDE [e.g. GTN in angina to dilate coronary arteries], carbon monoxide, etc.
Enzymatically generated
Cellular and molecular targets
Permeable to membranes (no receptor required)

51
Q

Define autocrine

A

A cell sending a signal to itself, e.g. IL-1 in response to monocytes.

52
Q

Define endocrine

A

Hormonal, long distance signals, e.g. insulin.

53
Q

Define neurocrine

A

Deriving from a nerve, e.g. noradrenaline.

54
Q

Define paracrine

A

Local cell signalling, e.g. thromboxane in clotting.

55
Q

Define juxtacrine

A

Cell signalling which requires contact through communicating cells, e.g. leukocytes and adhesion molecules on endothelial cells.

56
Q

Define metabolism

A

All of a living organism’s chemical reactions, which are integrated and form pathways (sequences of reactions leading to a particular end point).

57
Q

Define anabolic

A

Chemical reactions which lead to energy storage and biosynthesis.

58
Q

Define catabolic

A

Metabolic reactions that lead to the release of energy and degradation of compounds.

59
Q

Give examples of the main classes of nutrients, both energy producing and non-energy producing.

A

ESSENTIAL COMPOUNDS (specific range is key)
Vitamins
Minerals (electrolytes, macro etc.)
Essential amino acids
Essential fatty acids (Omega 3 and 6, needed to make eicosanoids [C20])

ENERGY-YIELDING COMPOUNDS
Carbohydrates
Fats
Proteins
- All converted to acetyl CoA, which is converted into ATP and CO2 by oxidative phosphorylation.
60
Q

Define enzyme

A

A protein catalyst which typically makes or breaks a covalent bond - can accelerate a reaction. Not typically consumed in the reaction. Can be a protein or RNA.
They stabilise the transition state of a chemical reaction, lowering the activation energy.
Can cause astonishing rate enhancements.

61
Q

Give examples of types of enzymes

A 
Oxidoreductases: catalyze oxidation-reduction reactions
	Cytochrome c (energy production)

Transferases: catalyze group transfer
Kinases (major drug target)

Hydrolayses: catalyze hydrolysis reactions
Proteases (normal digestion of proteins)

Lyases: catalyze addition of groups to double bonds or creation of double bond by group removal
	Adenylate cyclase (produces cAMP)
Isomerases: catalyze transfer of groups within a molecule
	DNA topoisomerase (common drug target for Antibiotics, Cancer)
Ligases: catalyze condensation reactions
	DNA ligase (DNA repair)
62
Q

Give examples of types of regulation of enzyme activity

A

Irreversible inhibition (e.g. nerve gas)
Reversible inhibition (competitive/non-competitive)
Negative feedback inhibition etc.
Also regulated by the environment - pathogens, temperature, pH etc.

63
Q

Give an example of the pathogenic mechanism of an inborn error of metabolism

A

Combined incidence of 1;5000, >200 errors known. Most autosomal recessive or X-l;inked inherited, usually a single gene defect in a key pathway.
Signs/symptoms due to toxic accumulation of substrate behind the block or deficiency of product after the block.

64
Q

Explain different approaches to development

A

Empirical
Milestones of development
e.g. Griffiths, Bayley scales of development

Psychoanalytic
e.g. Freud, Erikson

Cognitive
e.g. Piaget, Vygotsky (social)

Also behavioural and moral.

65
Q

Relate key stages of development to a conceptual framework

A

Erikson:
0-18 months = trust vs. mistrust = oral-sensory, development of attachment

18m-3y = autonomy vs. shame = motor development, will, illness as punishment

3-5y = initiative vs. guilt = play, social roles, magical ideas of illness

6-12y = industry vs. inferiority = social development, ‘germ’ concept of illness

12-18y = identity vs. role confusion, struggle for autonomy, peer approval, experimentation.

18-35y = intimacy and solidarity vs. isolation, permanent partnerships, adult roles.

35-55y = generativity vs. stagnation, cultural value transmission, diseases of affluence

55-death = integrity vs. despair, dealing with loss, impaired perception, mobility etc.

66
Q

Describe milestones of development

A

Sensory & motor (gross motor/fine motor and vision)
Communicative & linguistic (speech, language and hearing)
Social (emotional and behavioural)
Adaptive behaviour

Motor reflexes:

  • rooting disappears @ 3 weeks
  • stepping @ 2m
  • Moro @ 6m
  • Babinski @ 8-12m
  • eye blink, sucking and gag remain.
Head to toe acquisition:
Head control (some by 6 weeks) - by 4 months in sitting
Hand control - grasping from birth, holding toy by 3m, reaching @ 4m, passing @6m, casting @ 7-9m

Rolling 4-7m, sitting 6m, crawling 6m, pull to standing 9-12m, walking 12-18m.

Poor distance vision at birth, turning head to sound at birth.

67
Q

Outline the impact of untreated or poorly managed PKU

A

PKU = a genetic disorder where the body’s enzyme, phenylalanine hydroxylase (PAH), is missing or malfunctioning so that it cannot properly break down the amino acid, phenylalanine (phe).

Symptoms: cognitive disability, seizures, microcephaly, skin rashes, growth problems, hyperactivity, musty body odour, fair skin, hair and eyes. Social development: play and peer relationships impacted (autism/hyperactivity), family, cognitive development.

68
Q

What is attachment?

A

The formation of a strong, reciprocal emotional bond between an infant and a primary caregiver.
Indicated by proximity seeking, separation distress and pleasure when reunited, and general orientation towards specific individual.
0-2 months = pre-attachment
3-7 months = indiscriminate attachment (familiar people)
First discriminate attachment by 8 months, stranger anxiety by 9 months.

69
Q

What scale is commonly used for assessing development?

A

Bayley (1-42 months).

70
Q

What is the start codon?

A

ATG/AUG - methiamine.

Stop = TAA, TAG or TGA.

71
Q

What are the levels of protein structure?

A

Protein primary structure: sequence of amino acids.

Protein secondary structure: organisation of peptide chains into structures. – alpha helices etc.

Protein tertiary structure: 3D macromolecular structure.

Protein quaternary structure: assembly of multiple folded protein molecules in a multi-subunit complex.

72
Q

Describe the basic structure of an amino acid.

A

Central carbon
Basic amino group (H2N)
Hydrogen atom
Acidic carboxyl group (properties depend on this)
Side chain (R, contributes charge, polarity and hydrophobicity, plus 2ndary and tertiary structure - hydrogen bonds)

73
Q

Describe how genetic mutations can trigger subsequent protein conformational changes with disease implications.

A

A change in one base can alter which amino acid is produced, which can have a major effect depending on how different the amino acids are (e.g. charge).
Frame shifts have the most severe impact, as they change all subsequent acids. E.g. haemophilia - severity depends on mutation.

74
Q

What is post-translational modification of proteins?

A

the covalent and generally enzymatic modification of proteins during or after protein biosynthesis. Proteins are synthesized by ribosomes translating mRNA into polypeptide chains, which may then undergo PTM to form the mature protein product.

75
Q

Give an example of a second messenger system.

A

Where a ligand binding to a membrane receptor triggers an alteration in enzymatic activities driven by protein post-translational modifications (PTMs).
E.g. protein phosphorylation, AMP+protein kinase -> ADP
Phosphatase reverses it.
Transfer of phosphate may involve kinases activating each other = kinase cascade. MAPKKK.

76
Q

How can gene transcription be modulated by extracellular signals (epigenetic changes)?

A

Signals altering DNA methylation and histone PTMs. Inactive DNA is usually bound to the histone and extensively methylated, but acetyl transferase adds an acetyl group and changes polarity, breaking the bond between DNA and histone. This means it can now be found by transcription factors.

77
Q

What is a drug?

A

A chemical which affects the functioning of the body.

E.g. medicines, substances of abuse. Can have pharmacological/toxicological action.

78
Q

Should we use chemical, generic, or brand names?

A

Generic!

79
Q

Describe ways in which drugs may be classified.

A

There is no uniform system of classification. The main ones are therapeutic use, mode of action, and chemical structure.

80
Q

List the four major mechanisms of action for commonly-used drugs and give at least one example of a drug that acts by each mechanism.

A
  1. Direct physiochemical effect
    e. g. bulk-forming laxatives, antacids, osmotic diuretics, plasma expanders.
  2. Effect on transport systems
    Ion channels, e.g. local anaesthetics, calcium channel blockers, sulphonylureas
    Or carriers, e.g. loop diuretics
  3. Enzymes
    Competitively inhibit.
    E.g. antibiotics, trimethoprim and sulphonamides
  4. Interaction with receptors (mostly proteins)
    GPCR/ion channel/enzyme/intra-cellular

Four main kinds of regulatory protein are commonly
involved as primary drug targets, namely:
• receptors
• enzymes
• carrier molecules (transporters)
• ion channels.

81
Q

Describe the ways in which drugs acting on receptors exert their cellular effects, with reference to signal transduction mechanisms.
(Location, effector, coupling, examples)

A
  1. Ion channels (fast neurotransmitters) = in membrane, direct coupling, GABA.
  2. GPCRs = membrane, channel or enzyme effector, changes levels of G proteins (coupling), which affect second messengers and excitability. ACh/adrenoceptors.
  3. Kinase-linked receptors = membrane, protein kinases (effector) - protein phosphorylation -> gene transcription -> protein synthesis, direct, e.g. insulin, growth factors, cytokines.
  4. Nuclear receptors = intracellular, coupling via DNA, e.g. steroid receptors.
82
Q

Understand the main types of G-proteins - what are their second messengers, receptors, and agonists?

A

Gs increases cAMP, beta2 A2 and IP receptors, adrenaline, adenosine, prostacyclin.
Gi decreases cAMP, alpha 2 receptors, Adrenaline/noradrenaline.
Gq increases IP3 and Rho-kinase, alpha1, ETA, AT1 and V1 receptors. Adrenaline, angiotensin, vasopressin.

83
Q

How do bacteria characteristics influence the choice of antibiotic?

A

Depends on structure and metabolism of microorganism and host and groups of bacteria (gram positive or negative).

84
Q

What are the advantages and disadvantages of using a broad spectrum antibiotic?

A

+ can treat most infections, even if you don’t know what it is
- increased risk of resistance and side effects compared to a narrow spectrum antibiotic.

85
Q

What are the main three MOAs for antibiotics?

A
  1. Interfere with bacterial cell wall (peptidoglycan synthesis = cell lysis)
  2. Interfere with protein synthesis
  3. Interfere with replication of genetic material (DNA and RNA)
86
Q

What groups of antibiotics inhibit cell wall synthesis?

A

Beta-lactams and glycopeptides (e.g. vancomycin)

- resistance. Glycopeptides only active against gram positive.

87
Q

Give some examples of beta-lactams

A

Penicillins eg benzylpenicillin, flucloxacilin

Cephalosporins eg cephalexin, cefuroxime

Carbapenems eg imipenem, meropenem

Monobactams eg aztreonam

Cephamycins eg cefoxitin

88
Q

Which antibiotic classes inhibit protein synthesis?

A

Tetracyclines, Aminoglycosides, Chloramphenicol, Macrolides

Others: streptogramins, lincosamides (clindamycin), oxalazidonones (linezolid), ketolides, fusidic acid

89
Q

In what situations are aminoglycosides effective?

A

Bactericidal for G+ but especially G-, inactive against anaerobes.

GEM Year 1 Key Info (1 decks)

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