2016 1

HUBS1406 Summary Notes Abbreviations Abbreviation Meaning ACE Angiotensin converting enzyme

ADP Adenosine diphosphate

ATP Adenosine triphosphate

AV Atrioventricular

BP Blood pressure

C Carbon

Ca2+ Calcium ion

CCK Cholecystokinin

CNS Central nervous system

CO2 Carbon dioxide

DNA Deoxyribonucleic acid

ECG Electrocardiogram

EPO Erythropoietin

g Grams

GFR Glomerular filtration rate

GI Gastrointestinal

Hb Haemoglobin

H/H2/H+ Hydrogen/hydrogen ion

hCG Human chorionic gonadotropin

HCl Hydrochloric acid

HCO3- Bicarbonate ion

H2O Water

H2CO3 Carbonic acid

Ig Immunoglobulin

Kj Kilojoules

K+ Potassium ion

mm Hg Millimetres of mercury

N Nitrogen

Na+ Sodium ion

NaCl Sodium chloride

NADH Nicotinamide adenine dinucleotide - reduced

NH4+ Ammonium ion

O/O2 Oxygen

PNS Peripheral nervous system

PO42- Phosphate ion

RBC Red blood cell

RH Releasing hormone

RNA Ribonucleic acid

SA Sinoatrial

SH Stimulating hormone

WBC White blood cell

[ ] Concentration of whatever lies inside

↑ Increase

2016 2

Molecules of Life

Terminology Atomic number: number of protons in nucleus

Atomic weight: number of protons + neutrons in nucleus

Molecular weight: sum of the atomic weights of component atoms (NaCl: Na (23) + Cl (35) = 58)

Ion: atom that loses or gains an electron

Cation: loses an electron

Anion: gains an electron

Electrolyte: soluble inorganic molecules whose ions conduct an electrical current in solution

pH: expresses acidity/alkalinity of a solution

pH < 7 = acidic

pH > 7 = alkaline

pH = 7 = neutral

Atom Structure

Ionic & Covalent Bonds

Ionic Exchange of electron/s

2Na(s) + Cl2(g) → 2NaCl(s)

Covalent Sharing of electron/s

2H2(g) + O2(g) → 2H2O(l)

Positively charged subatomic particle found in nucleus

Neutrally charged subatomic particle found in nucleus

Negatively charged subatomic particle found around atoms

2016 3

Cell Biology

Plasma Membrane - Also known as cell membrane

- Makes up simple cell along with cytoplasm + organelles

- Like a mosaic

- Phospholipid bilayer:

o Tail: hydrophobic

o Head: hydrophilic

- Membrane protein molecules give cells immunological identity

- Receptors for hormones and chemical messages

- Involved in transport across membrane

Functioning Cell Parts

Nucleus - Contains DNA which directs all metabolic activities of cell

o Organised into chromosomes (23 pairs: one/pair from mother, one from father)

o Pair 23 = sex chromosomes

- Genes = sections of DNA that code for one polypeptide/characteristic

Mitochondria - Powerhouse of cell where ATP is produced

- Membranous structure

- More work → more ATP production → more mitochondria

Ribosomes - Proteins factories which consist of RNA + proteins

- Make all proteins needed by cell using instructions from RNA template from nucleus

Endoplasmic Reticulum - Interconnecting membranous tubes or channels

- Rough: studded with ribosomes, produce protein for export

- Smooth: synthesise lipids + steroid hormones, detoxify some drugs

Golgi Apparatus - Stack of flattened membranous sacs

- Receive proteins

- Synthesise proteins into secretory granules/packages

- Stores packages until needed

- Releases packages by exocytosis

Lysosomes - Packages created by Golgi apparatus

- Contain enzymes to break down large organic molecules (bacteria)

- Provide isolated environment for dangerous reactions

Cytoskeleton - Made of protein fibres

- Microfilaments: small fibres for structural support

- Microtubules: large fibres for movement of organelles, chromosomes, cell extensions

2016 4

Components of Blood

Blood

Characteristics - Sticky, opaque

- Scarlet/dark red

- pH: 7.35-7.45 (slightly alkaline)

- 38°C

- Approximately 8% of body weight

- Volume:

o Males: 5-6 L

o Women: 5-4 L

Functions

Transport

- Dissolved O2 and CO2

- Nutrients from GI tract to all cells

- Fat from stores in adipose tissue → cells

- Metabolic wastes for elimination (CO2 from lungs, urea from kidneys)

- Hormones + drugs from point of origin to site of action

Homeostasis

- Regulates body temperature by losing/gaining heat from environment + distributing heat around

the body

- Regulates pH by utilising buffers

- Regulates circulating blood volume due to osmotic pull of plasma proteins

Defence

- Fights infection due to containing WBCs, antibodies

- Contains clotting factors (proteins) + platelets to form clots + prevent excessive blood loss when

blood vessels burst

Plasma - 55% of blood

- 92% H2O, 7% plasma proteins, 1-2% other solutes

- Clotted plasma = serum

Plasma Proteins - Produced by liver

- Remain in blood due to large size incapable to diffuse through capillary wall

- H2O also trapped in blood vessels due to osmotic pressure

Albumin – 60%

- Maintain normal plasma osmotic pressure

- Carrier molecules for fatty acids, drugs + steroid hormones

Globulins – 35%

- Antibodies (immunoglobulins)

- Transport proteins (transferrin-iron)

2016 5

Healing

Connective Tissue Matrix Connective Tissue Microscopic Appearance Matrix Cells in Matrix

Loose

Jelly-like with collagen and elastic fibres

Fibroblasts

Cartilage

Collagen fibres and some elastin

Chondrocytes

Tendon

Close-packed collagen + small amount elastin

Fibroblasts

Ligament

Close-packed collagen + elastin

Fibroblasts

Bone

Collagen fibres with Ca2+ deposits

Osteoblasts Osteoclasts

Skin - Protection: physical barrier – epidermis + other layers made of epithelium + follicle

- Sensation: temp control, vibration, pressure and

pain using sensory nerves in dermis

- Absorption: partly – pores in epidermis, sweat

glands

Damage + Risks - Small wound

o Phagocytes ingest debris from wound

o Fibroblasts fill gap + heal

2016 6

Communication & Control Systems

Nervous System - Network of neurons

- Made up of:

o CNS: central nervous system – brain + spinal cord

o PNS: peripheral nervous system – cranial + spinal nerves

- Specialised tissue to send electrical impulses

- Nerve cell = neuron

- Neurons connect all organs + tissues

- Signals are rapid – allow body to respond quickly

Somatic Nervous System - Things we consciously control using skeletal muscle

- Functions are those voluntary actions such as:

o Walking, talking, breathing

Autonomic Nervous System - Things we unconsciously control using smooth muscle

- Functions are those involuntary actions such as:

o Blood vessel dilation, bladder emptying

o Heart rate changes – but are controlled by cardiac muscle rather than smooth

Sympathetic Division

- Produces ‘fight or flight’ response

- Activated when under stress

Parasympathetic Division

- Produces ‘rest and restore’ response

- Functions when calm

2016 7

Communication & Control Systems II

Feedback Loops

Negative - Almost all homeostatic mechanisms are negative feedback loops

- Change variable back to ideal value – output reduces effect

Positive - Output enhances original stimulus

- Childbirth, blood clotting

Body temp exceeds 37°C

Temp sensors in skin detect change

Temp control centre in brain

activated

Blood vessels dilate

Stimulus

Sensor

Control

Effector

Stimulus: head of baby pushes against cervix

causing a stretch

Sensor: nerve impulses from cervix sent to brain

Control: brain --> pituitary gland --> oxytocin -->

uterus

Effector: oxytocin stimulates uterine

contraction which pushes baby toward cervix

Birth of baby

2016 8

Reproduction

Meiosis - Cell division which results in 4 daughter cells (sex cells/gametes) with half the number of

chromosomes of the parent cell

- During fertilisation, male gamete and female gamete bind to form zygote with 23 pairs of

chromosomes (½ of each pair from each parent)

Meiosis I - Primary cell (usually gamete) divides to form two cells

- Each cell receives both copies of either maternal or paternal chromosomes → different to

mitosis where cell receives one maternal AND one paternal

- Cells now haploid with 23 double chromosomes

Meiosis II - Secondary gametes divide against into spermatids or ootids and polar bodies (23 chromosomes)

2016 9

Cardiovascular System - Also known as circulatory system

- Consists of:

o A series of vessels supplying all

structures + tissues of body

o A pump to keep the blood moving

through these vessels

The ‘Pump’ (Heart) - Keeps blood circulating through

97000km of vessels

- 4 chambers

o 2 on left

o 2 on right

o Allow heart to act as a double pump

- Between ribs 1-6

- In centre of chest but apex leans to left

1. Superior vena cava

2. Right atrium

3. Tricuspid valve

5. Pulmonary valve 4. Right

ventricle

6. Pulmonary artery

7. Lungs

8. Pulmonary veins

9. Left atrium

10. Mitral valve

11. Left ventricle

13. Aorta

Right coronary artery,

left coronary artery +

anterior

interventricular artery

supply cardiac muscle

with nutrients + O2

1. Inferior vena cava

12. Aortic valve

Blood transports:

- CO2 from tissues → lungs

- O2 from lungs → tissues

- Nutrients from gut → tissues

3 layers:

- Endocardium

- Myocardium

- Pericardium

o Fluid for protection in

movement and

lubrication

2016 10

Respiration

Functions of Respiratory System - Supply O2 to blood

- Remove CO2 from blood

Gas Exchange Membrane – Alveoli + Capillaries - Alveoli are ‘air sacs’ in lungs which maintain concentration gradients of O2 + CO2

o O2 – out into capillaries

o CO2 – into alveoli from capillaries

- Small bundles = large surface area

- Simple squamous epithelium layer is

thin = fast diffusion

- Gas exchange is compromised by:

o Poor blood supply

o Partial pressure of O2 + CO2

o Supply of gases

Defence Mechanisms - Alveoli – macrophage + surfactant secreting cell

- Upper RT – nasal hairs + turbinates

- Lower RT – cilia which line bronchus

The Airways – Bronchus + Bronchioles - Braced open by rings of cartilage which ↓ in bronchioles

- Degree of constriction determines resistance to air flow into airways

o Bronchodilation: relaxed

o Bronchoconstriction: constricted

- ↓air flow = ↑ resistance as seen in obstructive diseases such asthma, bronchitis, emphysema

System of Bellows – Chest Wall + Muscles of Respiration

Muscles of Respiration - Diaphragm = skeletal muscle under conscious control

- Accessory muscles only utilised when ↑ effort is required

2016 11

Digestion + Metabolism

Principal Digestive Enzymes

Sites of Absorption

Small intestine - Fats

- Lipids

- Sugars

- Peptides

- Amino acids

Large intestine - Sodium

- Water

- Non-fat soluble vitamins

Metabolism - All chemical reactions occurring in all cells of the body

- Anabolism: building up of substances from simple to more

complex

o Require energy input

- Catabolism: breaking down of complex substances into simpler ones

o Release energy

- Energy to power growth + repair:

o Amino acids

o Fats/lipids

o Glucose

- Energy to power activities:

o Glucose

o Fats/lipids

o Amino acids

Glucose - Leaves liver from hepatic vein

- Some is stored as glycogen in muscles

- Used to produce ATP

- Used to maintain BGL

- Some converted to fat and stored

- Cannot be stored in brain needs constant supply

Enzyme Site of Action Substrate Product

Amylase Saliva, pancreas Carbohydrates Maltose

Lipase Saliva, pancreas, stomach

Fats/lipids Fatty acids, glycerol

Pepsin (protease) Pancreas, stomach Proteins Peptides, amino acids

Nucleases Pancreas Nucleic acids Nucleotides

Bile salts Small intestine Fat globules Fat droplets

1g carbs = 1g protein (4kJ)

1g fat = 38kJ

2016 12

The Kidney

Urinary System

Kidney Functions Red text indicates symptoms of kidney failure

Nitrogenous Waste Elimination - How excess amino acids are broken down + excreted

- Rate of excretion = rate of production of nitrogenous wastes

- More due to ↑ metabolic activity

- Excretion rate↓ → level of waste in blood↑

o Uraemia = urea in the blood

o BUN = blood urea nitrogen

- Uraemia = pericarditis, pruritus, nausea, vomiting + anorexia, neurological disturbances,

haemostasis problems → ↑ bleeding

Drug Metabolite Elimination - Removal of products from drug metabolism

- Drugs metabolised/processed by liver + secreted from kidney

- Fat soluble – must go through liver first to ensure drug is water soluble + can pass with urine

- Drugs not metabolised potential overdosing

Electrolyte Balance - Sodium and potassium balance and other charged cations

Control Blood Pressure - Na+ levels change → H2O levels change → BP changes

- Causes Na+ and H2O retention → increases circulating blood volume →

vasoconstriction due to angiotensin II → long term BP control

- Hypertension, heart failure, oedema

Acid-Base Balance - Maintains blood pressure within narrow limits and controls buffer reaction, can remove H+ (lungs

CO2)

Vena cava

Aorta Adrenal gland

Kidney

Bladder

Urethra

Ureters

See Figure 1