Human Biology Unit 3 and 4 WACE ATAR

Gonadotropins (FSH, LH) Growth hormone THS ACTH Prolactin

Anterior pituitary (releasing and inhibiting factors)

Thyroxine

Thyroid gland

Thymosins

Thymus gland

Parathyroid hormone

Parathyroid glands

Adrenaline, noradrenaline

Adrenal medulla

Costicorteroids, aldosterone

Adrenal cortex

Insulin and glucagon

Pancreas

Oxytocin, ADH

Hypothalamus hormones

Oxytocin and ADH

Posterior pituitary

Melatonin

Pineal gland

Passive artificial immunity

Antibodies are injected into the bloodstream

Active natural immunity

ability to manufacture antibodies results from an attack of the disease

active artificial immunity

Ability to manufacture antibodies results from being given an antigen by vaccination.

Immunisation

Programming the immune system so that the body can respond rapidly to infecting micro-organisms

vaccination

artificial introduction of antigens of pathogenic organisms so that the ability to produce the appropriate antibodies is acquired without the person having to suffer the disease

Antibiotics

compounds that block the growth and reproduction of bacteria

Bacteria

single-celled organisms that lack a nucleus; prokaryotes

Virus

A tiny, nonliving particle that invades and then reproduces inside a living cell.

exocrine gland

A gland (as a sweat gland, a salivary gland, or a kidney) that releases a secretion external to or at the surface of an organ by means of a canal or duct.

endocrine gland

Glands of the endocrine system that release hormones into the bloodstream via the extracellular fluid

hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect target tissues or organs

Protein and amine hormones

Group of hormones that work by attaching to receptor proteins in the membrane of the target cell, activating a secondary messanger

steroid hormones

enter the target cells and have a direct effect on the DNA of the nucleus

Hormone function

activate a certain gene so that a specific enzyme/protein is produced

hormone function

change the structure of an enzyme so they are turned on/off

hormone function

change the rate of production of an enzyme by changing the rate of transcription/translation

enzyme amplification

A series of chemical reactions in which the product of one step is an enzyme that produces an even greater number of product molecules at the next step

hormone clearance

Hormone signals must be turned off when they have served their purpose
Most hormones are taken up and degraded by liver and kidney
Excreted in bile or urine

negative feedback

response is opposite of the stimulus caused by secretion

releasing factors

Stimulate the release of a hormone

inhibiting factor

slow down the secretion of a hormone

Hypothalamus

Located at the base of the brain, regulates body temperature, water balance and heart rate

Pituitary gland

Lies under the hypothalamus, joined by the infundibulum

anterior lobe of pituitary gland

adenohypophysis, release hormones that regulate bodily activity secreted into target cells. Ie. Gonadotropins, Growth hormone, TSH, ACTH
controlled by releasing and inhibiting factors

posterior lobe of pituitary gland

neurohypopysis, does not make hormones, stores and releases hormones made in hypothalamus, releasing Oxytocin and ADH, produced by neurosecretory cells.

Pineal gland

secretes melatonin, deep inside the brain, decreased after puberty. Stimulated by darkness, inhibited by light

Thyroid gland

produces hormones that regulate metabolism, body heat, and bone growth, located in the neck below the larynx. Secrete thyroxine (metabolism) release energy and maintain body heat. Secreted in response to TSH from anterior pituitary

thymus gland

located in the mediastinal cavity anterior to and above the heart; secretes thymosin, influence the maturation of T-lymphosites

Parathyroid glands

small pea-like organs that regulate calcium and phosphate balance in blood, bones, and other tissues

adrenal medulla gland

epinephrine, sympathetic nervous system, prepare body for threatening situations,
and norepinephrine, increased rate and force of heartbeat

Adrenal cortex gland

corticosteroids, reduce sodium and increase potassium, cortisol, produce normal metabolism, helps to withstand stress, repair damaged tissues

pancreas gland - exocrine

gland found under stomach which sits alongside the duodenum, both endocrine and exocrine. exocrine; secrete digestive enzymes into small intestine through pancreatic duct

pancreas gland - endocrine

gland found under stomach which sits alongside the duodenum, islets of langerhands secrete insulin (reduce amount of glucose in the blood) and glucagon (increase amound of glucose in the blood, and promotion of glycogen to glucose in the liver)

Gonad glands

androgens, male sex hormones produced by testes, oestrogens and progesterone, female sex hormones prouduced by ovaries

central nervous system

'control centre' brain and spinal cord

peripheral nervous system

the sensory and motor neurons that connect the central nervous system to the rest of the body

Ganglia

Group of nerves cell bodies in the PNS

sensory fibres

carry impulses into the CNS

motor fibres

carry impulses away from the CNS

ventral root

contains axons of motor neurons

dorsal root

the sensory branch of each spinal nerve

dorsal root ganglion

a nodule on a dorsal root that contains cell bodies of afferent spinal nerve neurons

afferent (sensory) neurons

fibres that carry impulses into the CNS by sensory nerve cells from receptors

efferent (sensory) neurons

Carries nerve impulses away from the central nervous system to effectors such as muscles or glands

fight or flight

a reaction caused by adrenaline that prepares one to either fight the stressor or take flight and escape.

Homeostasis

a balance between sympathetic and parasympathetic system

hormonal

responses are slower, travel in the bloodstream can take several seconds to several days

hormonal

slower acting, longer responses

hormonal

chemicals that are usually transported via the blood

hormonal

travel to all parts of the body, and are carried by the blood and often affect a number of different organs

nervous

responses are more rapid, milliseconds, travel along nerve fibres

nervous

immediate yet short response, cease of stimulus means cease of response

nervous

electrochemical messages that travel along the membrane of a neuron

nervous

nerve impulses that travel along a nerve fibre to a specific part of the body and often only influence one effector

Noradrenaline, ADH, dopamine

Function as both hormones and neurotransmitters

Protein and Amine hormones

attach to the cell membrane, activate a secondary messenger, water soluble, activate certain enzyme, change rate of particular reaction, form a hormone-receptor complex

Receptors

- specific to a particular hormones
- limited in number, so when saturated there can be no increase in reaction

steroid hormones

diffuse directly into cell, receptors on the organelles inside the cell, lipid soluble to they go straight through bilipid bilayer, activated genes by controlling formation of particular proteins, form a hormone-receptor complex.

hormones ...

alter the function of cells by changing
- types
- activity
- quantity
of proteins produced

dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

cell body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

Axon

A threadlike extension of a neuron that carries nerve impulses away from the cell body.

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

grey matter

The portions of the central nervous system that are abundant in cell bodies of neurons rather than axons. Unmyelinated.

schwaan cells

Type of glial cell. Wraps around axons. produces myelin cover

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

Neurilemma

additional external myelin sheath that is formed by Schwann cells and found only on axons in the peripheral nervous system

resting membrane potential

- sodium ion channels are closed
- potassium ion channels are closed
- -70mV membrane potential

stimulus received

- some sodium ion channels open
- voltage-gated ion channels remain closed
- Na+ ions move into the cell via diffusion
- reduces potential difference
- if reaches -55mV threshold, an action potential is triggered

hyperpolarisation

- K+ ion channels are slow to close
- more K+ exit the cell than necessary
- membrane potential is temporarily more negative than resting potential
- K+ ion channels close
- resting membrane potential is restored by Na+/K+ ion pumps and natural movement of ions down a concentration gradient

sensory neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

multipolar neurons

A neuron that has many/multiple extensions from the cell body

unipolar neurons

Neuron that has a short, single projection from the cell body

bipolar neurons

A neuron that has only two projections (one axon/one dendrite) from the cell body

all-or-nothing

Refers to the fact that a neuron either conducts an action potential or it does not.

protection of the CNS

bone, meninges, cerebrospinal fluid, blood-brain barrier

vertebral canal

formed by vertebral column and contains spinal cord and the beginnings of spinal nerves

cranium

the portion of the skull that encloses the brain

cerebrospinal fluid (CSF)

Fluid produced in the ventricles of the brain that flows in the subarachnoid space and bathes the meninges.
occupies space between the middle and inner layers of meninges
circulates through cavities in the brain and through the canal in the center of the spinal cord
acts as a shock absorber and supports the brain

Meninges

three protective membranes that surround the brain and spinal cord
outer is tough and fibrous
middle is a loose mesh of fibers
inner layer is delicate

cerebrospinal fluid function

1. protect
2. support
3. transport

cerebrum

Area of the brain responsible for all voluntary activities of the body, biggest part of the brain, outer surface is grey matter 2-4mm thick, below that is white matter, below that is the basal ganglia

basal ganglia

structures in the forebrain that help to control movement

corpus collosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

sensory areas

conscious awareness of sensation

motor areas

control voluntary movement

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance