Topic 6: Human Physiology

Cardiac muscles

________ are unable to contract properly with the shortage of ATP and become irregular and uncoordinated.

immunodeficiency virus

Human ________ (HIV): HIV invades and destroys helper T cells and as a result antibodies can not be produced.

Airways

________ for ventilation: Air is carried to the lungs in the trachea and bronchi and then to the bronchioles, which have alveoli.

ATP

● Do not synthesise proteins and depend on a host for ________ synthesis.

Valves

________ in veins: Ensure circulation by preventing backflow.

Sex determination

________ in females: Estrogen and progesterone cause prenatal development of female reproductive organs and female secondary sexual characteristics during puberty.

Viruses

________ and antibiotics: Viral diseases can not be treated using antibiotics because they lack a metabolism.

Positive feedback

________, as raised levels of estrogen during puberty cause development of female secondary sexual characteristics.

Myelination

________ is the formation of many layers of phospholipid bilayers, created by Schwann cells.

O

________ Stimulates the liver cells to break glycogen down into glucose and release the glucose.

Villi

________ and the surface area for digestion: ________ increase the surface area of the epithelium (mucosa) over which absorption is carried out.

Emphysema

________: Results in larger air sacs with thicker walls.

Thyroxin deficiency

________: Lack of energy, forgetfulness and depression, weight gain, constipation.

Thyroxin

________: Secreted by thyroid gland to regulate metabolic rate and control body temperature.

Capillaries

________: Allow the exchange of materials between cells in tissue and blood in the capillary.

Local currents

________: Cause each successful part of the axon to reach the threshold potential.

viral infections

● Using antibiotics to treat ________ are redundant, and contribute to the overuse of antibiotics, which contributes to antibiotic resistance.

concentration gradients of oxygen

4 Gas exchange: Ventilation: Maintains ________ and carbon dioxide between air in alveoli and blood flowing in adjacent capillaries.

Acetylcholine

________: Used as a neurotransmitter.

O Low

________- density lipoproteins (LDL) accumulate, and phagocytes are attracted due to signals from endothelial cells.

FSH

Promotes thickening and maintenance of the endometrium and inhibits ________ and LH secretion by the pituitary gland.

gas exchange

Type I pneumocytes: Type I pneumocytes are extremely thin alveolar cells that are adapted to carrying out ________.

Atherosclerosis

________: Caused by fatty tissue (atheroma) developing adjacent to the endothelium in artery walls.

Starch digestion

________ in the small intestine: Starch is a macromolecule composed of alpha glucose monomers linked together.

heartbeat

Initiating the ________: ● SA node acts as a pacemaker.

Melatonin

________: Is secreted by the pineal gland to control circadian rhythms.

Veins

________: Collect blood at low pressure from body tissue and return it to the atria from capillary networks.

Occlusion

________ in the coronary arteries occurs when an atheroma develops, hardening the artery and damaging them.

O Permeability

________ does however vary, and depends on the needs of the tissues they perfuse.

Intramuscular injections of FSH

O ________ and LH are administered for 10 days to stimulate follicle development.

Large intestine

● ________: reabsorbs water; carbohydrates are digested further by symbiotic bacteria; formation /storage of faeces.

Pancreatic juice

________: Secretes enzymes into the lumen of the small intestine.

Fibrin production

________: Conversion of fibrinogen to fibrin by thrombin, which is activated by prothrombin activator from prothrombin to thrombin.

surface tension

Reduces ________ and prevents water from adhering to the sides of the alveoli during exhalation.

Synaptic transmission

________: Nerve impulse reaches the end of a neuron and depolarises the presynaptic membrane.

o Amylose

● Consists of two molecules: ________ (1, 4) unbranched o Amylopectin (1, 6) branched.

Amylase

________ can not break down 1, 6 bonds due to its active site specificity.

Enzyme lysozyme

________ gives anti- bacterial properties.

artificial pacemaker

● Can be replaced by a(n) ________ (placed under the skin with electrodes attached to wall of the heart)

Coronary thrombosis

________: Coronary arteries supply blood to the walls of the heart- oxygen and glucose for cell respiration.

microvilli transport

transporter proteins in ________ one molecule of sodium and glucose together into the epithelium.

● Acetylcholinesterase

________ does not break down neonicotinoids, so the binding is irreversible.

Leptin

________: Secreted by cells in adipose tissue and acts on the hypothalamus of the brain to inhibit appetite.

weak immune

O Results in ________ system due to acquired immune deficiency syndrome (AIDS)

Platelets

________ and blood clotting: Clotting factors are released from ________.

Neonicotinoids

________: Block synaptic transmission at cholinergic synapses in insects by binding of neonicotinoid pesticides to acetylcholine receptors.

small intestine

Digestion in the ________: Enzymes digest most macromolecules in food into monomers in the ________.

blood flow

O Vasoconstriction restricts ________ and vasodilation increases it.

Repolarization

________: closing of the Sodium voltage gated channels and the subsequent opening of the potassium voltage gated channels.

Glucose

________: Glucose can not pass through simple diffusion because it is polar and hydrophilic.

● Oesophagus

Peristalsis from mouth to stomach

● Stomach

Churning into chime

● Liver

Secretion of surfactants in bile break up lipid droplets

● Large intestine

reabsorbs water; carbohydrates are digested further by symbiotic bacteria; formation/storage of faeces

● Muscle layers

Longitudinal/circular muscle

● Sub-mucosa

Tissue containing blood/lymph vessels

Pancreatic juice

● Secretes enzymes into the lumen of the small intestine

Digestion in the small intestine

● Enzymes digest most macromolecules in food into monomers in the small intestine

o Types of enzymes are

nucleases, maltase, lactase, sucrase, exopeptidases (break peptide chains into dipeptides) and dipeptidases (break dipeptides into amino acids)

Villi and the surface area for digestion

● Villi increase the surface area of the epithelium (mucosa) over which absorption is carried out

● Glucose

o Glucose cannot pass through simple diffusion because it is polar and hydrophilic

Starch digestion in the small intestine

● Starch is a macromolecule composed of alpha glucose monomers linked together

● Consists of two molecules

o Amylose (1,4) unbranched o Amylopectin (1,6) branched

Artery walls

● Have muscle and elastic fibres in their walls

● Tunica externa

tough outer layer

Arterial blood pressure

● Smooth and elastic fibres maintain blood pressure between pump cycles

● Vasoconstriction

contraction of circular muscles

Capillaries

● Allow the exchange of materials between cells in tissue and blood in the capillary

Veins

● Collect blood at low pressure from body tissue and return it to the atria from capillary networks

Valves in veins

● Ensure circulation by preventing backflow

Present in most Double circulation

● Lungs are supplied with blood by a separate circulation

● Pulmonary circulation

to and from the lungs

● Systemic circulation

to and from all other organs

Atherosclerosis

● Caused by fatty tissue (atheroma) developing adjacent to the endothelium in artery walls

● Coronary occlusion

o Narrowing of blood arteries that supply the heart with oxygen

● Caused by

o High LDL intake, diabetes, high blood pressure, production of trimethylamine N-oxide by microbes in intestine

Initiating the heartbeat

● SA node acts as a pacemaker

Atrial and ventricular contraction

● SA nodes electrical signals stimulate contraction in walls of atria and ventricles

Specific part of the brain

cardiovascular centre in the medulla

Cuts and clots

● Cuts in the skin are sealed by blood clots

Platelets and blood clotting

● Clotting factors are released from platelets

Fibrin production

● Conversion of fibrinogen to fibrin by thrombin, which is activated by prothrombin activator from prothrombin to thrombin

● Infection of wounds results in pus

large amount of phagocytes aggregating at the infected site

Antibody production

● Lymphocytes produce antibodies providing specific immunity

Antibodies

● Have a hyper-variable region that binds to an antigen

Human immunodeficiency virus (HIV)

● HIV invades and destroys helper T cells and as a result antibodies cannot be produced

Antibiotics

● Antibiotics block metabolic processes in prokaryotic cells, resulting in their death o These metabolic processes are not present in viruses (they don't have metabolic processes as they rely on the host cells to carry out their metabolic processes for them

Viruses and antibiotics

● Viral diseases cannot be treated using antibiotics because they lack a metabolism

Resistance to antibiotics

● Bacteria have evolved with genes that confer resistance to antibiotics

Some strains have developed such as MRSA

methicillin resistant staphylococcus aureus

WE DON'T NEED TO KNOW THIS ^ Ventilation rate

● Number of times air is drawn in/expelled in a minute

● Tidal volume

volume of air drawn in and expelled with each inhalation or exhalation

Type I pneumocytes

● Type I pneumocytes are extremely thin alveolar cells that are adapted to carrying out gas exchange

Type II pneumocytes

● Type II pneumocytes secrete a solution containing surfactant

Airways for ventilation

● Air is carried to the lungs in the trachea and bronchi and then to the bronchioles, which have alveoli

Pressure changes during ventilation

● Muscle contractions cause the pressure changes inside the thorax that force air in and out of the lungs to ventilate them

● Passive smoking

non-smokers inhale tobacco smoke exhaled by smokers

● Air pollution

diesel exhaust fumes, nitrogen oxides

● Radon gas

radioactive gas that leaks out of certain rocks

Emphysema

● Results in larger air sacs with thicker walls