Human Biology Chapter 1-5

Front 1

Case Study

Back 1

In-depth investigation into a person or situation.

Front 2

Longitudinal Study

Back 2

Longer version of a case study

Front 3

Scientific Method

Back 3

Recognise Problem/Define question

Collection of information/research

Hypothesis and prediction

Test hypothesis

Analyse/interpret data

Draw conclusions

Report

Front 4

Ethics

Back 4

A set of moral principles or values

Front 5

Replication

Back 5

Having identical experiments running at the same time or testing a large sample space

Front 6

Validity

Back 6

Does it test what it is meant to test

Front 7

Model

Back 7

Simple representation of an idea or process

Front 8

Exocrine glands

Back 8

A gland that secretes into a duct that carries the secretion to the surface of the body cavaties e.g. sweat glands, mucous glands and salivary glands.

Front 9

Endocrine glands

Back 9

A gland that secretes hormones directly into adjacent tissue (ductless gland) e.g. thymus, adrenal glands and the ovaries.

Front 10

Hormone

(page 26 has many types of hormones)

Back 10

A chemical secreted by an endocrine gland that affects functions of a cell or organ. Carried in blood. Can activate certain genes, turn off or on enzyme or change rate of production.

Front 11

Protein and Amine

Back 11

Attach to receptors in the cell membrane. Receptor proteins are specific (lock and key concept).

Front 12

Paracrines

Back 12

local hormones; used to communicate between cells, move through extracellular fluid.

Front 13

Steroids

Back 13

Bind with a receptor inside the cell.

Front 14

Enzyme amplification

Back 14

When a hormone activates many enzymes.

Front 15

Releasing factors

Back 15

Hypothalamus secretes it to stimulate release of a hormone.

Front 16

Inhibiting factors

Back 16

Hypothalamus secretes it to slow down secretion of a hormone.

Front 17

Hypothalamus

Back 17

Located at the base of the brain, towards the back. Regulates basic functions of the body such as body temperature, water balance and heart rate.

Front 18

Pituitary gland

Back 18

Underneath the hypothalamus, consists of an anterior and posterior lobe. It is in fact joined to the hypothalamus, via the infundibulum.

Front 19

Gonadotropins

Back 19

Hormones that affect the gonads, ovaries and testes.

Front 20

Stimulating hormone (FSH)

Back 20

Stimulates development of the follicles that contain eggs in the ovaries, in women. For men, it stimulates production and maturation of sperm in the testes.

Front 21

Luteinising Hormone (LH)

Back 21

Works with FSH in female to bring about ovulation and to form the corpus luteum after ovulation. In the male, it stimulates interstitial cells in the testes to secrete male hormones.

Front 22

Growth hormone (GH)

Back 22

Stimulates body growth. Increases rate at which amino acids are taken up by cells and built in proteins. It is secreted continually to the body to maintain size of organs once maturity is reached.

Front 23

Thyroid-Stimulating Hormone (TSH)

Back 23

Stimulates production and release of hormones in the thyroid gland.

Front 24

Adrenocorticotropic Hormone (ACTH)

Back 24

Controls production and release of some of the hormones from the cortex of the adrenal glands.

Front 25

Prolactin (PRL)

Back 25

Works with other hormones to initiate and maintain milk secretion in females.

Front 26

Oxytocin (OT)

Back 26

Stimulates contractions of the muscles in the uterus.

Front 27

Antidurectic hormone (ADH)

Back 27

Causes kidneys to remove water from urine that is forming. Water is returned to bloodstream. So ADH retains fluid within the body.

Front 28

Pineal Gland

Back 28

Secretes melatonin which regulates sleep.

Front 29

Thyroid

Back 29

Secretes Thryoxine

Targets most cells

Increases metabolic rate

Front 30

Parathyroids

Back 30

Secretes Parathyroid hormone

Targets bones and kidneys

Increases level of calcium in blood

Front 31

Thymus

Back 31

Secretes Thymosins

Secretes T lymphocytes

Stimulates development and mature of T lymphocytes

Front 32

Adrenal Cortex

Back 32

Secretes Corticosteriods (Aldosterone and cortisol)

Targets kidney and most cells

Increases reabsorption of sodium ions and secretion of potassium ions. Promotes normal metabolism.

Front 33

Adrenal Medulla

Back 33

Secretes adrenaline and noradrenaline

Targets most tissues

Prepares body for fight or flight responses, reinforces effects of sympathetic nervous system

Front 34

Pancreas

Back 34

Secretes Insulin and Glucagon

Targets most cells and liver and fat storage tissues

Stimulates uptake of glucose (lowers blood glucose level). Stimulates breakdown of glycogen and fat (Increases blood glucose level).

Front 35

Testes

Back 35

Secretes Andriogens

Targets many tissues

Stimulates sperm production

Front 36

Ovaries

Back 36

Secretes Oestrogens and Progestrerone

Targets many tissues and uterus and mammary glands.

Regulates menstrual cycle and pregnancy and milk secretion.

Front 37

Nervous system

Back 37

The communication network and control centre of the body. Maintains homeostasis, shares this task with the endocrine system.

Front 38

Central Nervous System (CNS)

Back 38

Consists of the brain and spinal cord. Control centre for the entire nervous system.

Front 39

Peripheral Nervous System (PNS)

Back 39

The nerves that connect to the spinal cord. Divides into the motor and sensory paths.

Front 40

Nueron

Back 40

Basic structural and functional unit of the nervous system. Vary in shape but all consist of a cell body, dendrites and axons.

Front 41

Interneurons (connector neurons)

Back 41

Join the sensory and motor neurons. Found in the brain and spinal cord.

Front 42

Cell Body

Back 42

Contains the nucleus.

Front 43

Dendrites

Back 43

Short extensions of the cytoplasm of the cell body. Carry messages (nerve impulses), into the cell body.

Front 44

Axon

Back 44

Usually a single, long extension of the cytoplasm. Carries messeages away from the cell body.

Front 45

Myelinated

Back 45

Covered with a myelin sheath. Carry impulses faster than an unmyelinated nerve. White matter.

Front 46

Unmyelinated

Back 46

Slower than myelinated. Do not have a white sheath and have grey matter.

Front 47

Schwann Cells

Back 47

Special cells which wrap around nerve fibres to form the myelin sheath.

Front 48

Nodes of Ranvier

Back 48

A gap in the myelin sheath of a nerve fibre.

Front 49

Neurilemma

Back 49

The outermost sheath of the Schwann cell surrounding a nerve fibre.

Front 50

Sensory neuron

Back 50

Carries nerve impulses from the sensory receptors in organs and skin to the CNS.

Front 51

Motor neuron

Back 51

Carries nerve impulses from the CNS to the muscles and glands (collectively called effectors).

Front 52

Interneurons (association neurons, connector neurons or relay neurons)

Back 52

Link sensory and motor neurons. Found in the CNS.

Front 53

Multipolar neurons

Back 53

One axon.

Many dendrites.

Most common type of neuron.

Found mainly in CNS and as motor neurons.

Front 54

Bipolar neurons

Back 54

One axon.

One dendrite.

Commonly found in the eye, ear and nose.

Front 55

Unipolar neurons

Back 55

One axon.

Cell body is on side of axon.

Commonly found as sensory nerves.

Front 56

Nerve terminology

Back 56

Neuron: a nerve cell

Nerve fibre: any long extension of cytoplasm of a nerve cell body, although the term usually refers to an axon.

Nerve: a bundle of nerve fibres held together by connective tissue.

Front 57

Synapse

Back 57

The junction between branches of adjacent neurons.

Front 58

Neuromuscular junction

Back 58

The junction between branches of a motor nerve cell and a muscle fibre; also called the motor end plate.

Front 59

Nerve impulse

Back 59

The message that travels along a nerve fibre.

Front 60

Electrochemical change

Back 60

The change in electrical voltage brought about by changes in the concentration of ions inside and outside the cell membrane.

Front 61

Saltatory conduction

Back 61

Term given to the action of how a nerve impulse 'jumps' from node to node.

Front 62

Resting membrane potential

Back 62

-70mV

Front 63

Membrane potential

Back 63

The differences in concentration between intracellular fluid and extracellular fluid.

Front 64

Sodium-Potassium pump

Back 64

The active diffusion of Na+ and K+ across the membrane of the cell. They work by regulating the positive negative relationship between the membranes.

Front 65

Polarised

Back 65

The state in which the outer environment (extracellular fluid) is more positively charged than the inner environment (intracellular fluid).

Front 66

How it works...(membrane potential)

Back 66

Extracellular - More Na+ than K+ (also a high concentration of Cl-)

Intracellular - More K+ than Na+ (also high concentration of insoluble molecules)

Na+ is MORE positive than K+.

Pumps and channels maintain the potential difference.

Front 67

Depolarised

Back 67

When the extracellular fluid becomes negatively charged compared to the intracellular fluid which becomes more positively charged.

Front 68

All-or-none response

Back 68

A sarcomere will either fully contract or not at all.

Front 69

Action potential

Back 69

When sodium ions move into a nerve cell at a particular place on the membrane; this change is transmitted along the cell membrane as a nerve impulse.

Front 70

Refractory period

Back 70

The period in which the nerve fibre must 'recharge' and during this period it CANNOT be stimulated.

Front 71

Neurotransmitters

Back 71

Collective name given to the substances that diffuse across the synapse, from axon terminal to dendrites.

Front 72

Ganglia

Back 72

A group of cell bodies.

Front 73

Cranial nerves

Back 73

Twelve pairs of nerves which arise from the brain. E.g. optic or auditory.

Front 74

Sensory fibres

Back 74

Carry impulse to the CNS.

Front 75

Motor fibres

Back 75

Carry impulse away from CNS.

Front 76

Spinal nerve

Back 76

31 pairs of nerves arise from the spine.

Front 77

Ventral root

Back 77

Contains the axons of motor neurons that have their cell bodies in the grey matter.

Front 78

Dorsal root

Back 78

Contains the axons on sensory neurons that have their cell bodies in a small swelling in the dorsal root ganglion.

Front 79

Afferent division (sensory)

Back 79

Carry messages from the PNS to the CNS. From receptors in the skin or organs to the CNS.

Front 80

Efferent division (motor)

Back 80

Carry impulses away from the CNS. Divides into somatic and autonomic.

Front 81

Somatic division

Back 81

Takes impulses from CNS to skeletal muscles.

Front 82

Autonomic division

Back 82

Takes impulses from CNS to heart, involuntary muscle and glands. Divides into sympathetic and parasympathetic.

Front 83

Sympathetic division

Back 83

Prepare body for fight or flight response.

Front 84

Parasympathetic division

Back 84

More active in controlling homeostasis.

Front 85

Fight or flight response

Back 85

Rate and force of contraction of heart increases

Rate and depth of breathing increases

Blood glucose level rises

Sweat gland secretion increases

Front 86

Nerves vs hormones

Back 86

Nervous system is much faster (milisecond response)

Nervous system stops with stimulus.

Nervous = electrochemical

Endocrine = chemicals (hormones)

Nerves are specific (target area) of muscles.

Endocrines are specific or general of body.

Front 87

Three structures protecting the CNS

Back 87

Bone

Membranes called meninges

Cerebrospinal fluid (CSF)

Front 88

Cranium

Back 88

Part of the skull that houses the brain

Front 89

Vertebral canal

Back 89

Opening in the spinal cord where the vertebrae runs through.

Front 90

Meninges

Back 90

3 layers of membranes which cover the brain and spinal cord

Front 91

Cerebrospinal fluid

Back 91

A "shock-absorbant" fluid located between the middle and inner layers of meninges.

Front 92

Cerebrum

Back 92

Biggest part of the brain (85%)

Consists of grey matter (outer layer) and white matter (inner layer)

Front 93

Corpus callosum

Back 93

Large bundle of nerve fibres that connect the two hemispheres. Cannot be seen on outside of the brain. Located at the base of the longitudinal fissure.

Front 94

Cerebellum

Back 94

Underneath rear part of the brain. Looks separate to the brain but in fact just has less convolutions. Located under the cerebrum. Looks bulbous. Controls posture, balance and fine coordination of skeletal muscles.

Front 95

Medulla oblongata

Back 95

Joins brain and spinal cord. Cardiac centre: regulates rate and force of heartbeat,

respiratory centre: control rate and depth of breathing, vasomotor centre: regulates diametre of blood vessels. Also regulates swallowing, sneezing, coughing and vomiting.

Front 96

Hypothalamus

Back 96

Not seen on outside of brain. Functions include: regulate body temperature, food and water intake, regulate heart rate, blood pressure, diametre of pupils, contraction of urinary bladder, emotional responses etc.

Front 97

Convolutions (a.k.a gyri)

Back 97

Folds of the brain which produces ridges.

Front 98

Sulci

Back 98

Separate the convolutions, by shallow downfolds.

Front 99

Fissures

Back 99

A deep sulci

Front 100

Longitudinal fissure

Back 100

Almost separates the cerebrum into two separate hemispheres.

Front 101

5 cerebral lobes

Back 101

frontal, temporal, occipital, parietal and insula.

Front 102

Three types of tracts in white matter

Back 102

Tracts that:

connect the cortex in the same hemisphere

carry impulses between left and right hemisphere

connext cortex to other parts of brain and spinal cord

Front 103

Sensory area

Back 103

Receive and process nerve impulses from senses.

Front 104

Motor area

Back 104

Send impulses to muscles, especially for voluntary movement

Front 105

Association areas

Back 105

Interpret information from the senses and make it useful

Front 106

Spinal cord

Back 106

Located between foramen magnum and second lumbar vertebrae.

Front 107

Ascending tracts

Back 107

Carry impulses from sensory axons to brain.

Front 108

Descending tracts

Back 108

Carry impulses from brain to motor neurons.

Front 109

Receptors

Back 109

Detects change in the bodies internal and external environment. Can be grouped together in a sense organ (light receptors in eyes).

Front 110

Thermoreceptors

Back 110

Respond to heat and cold. Found in the skin.Reports to hypothalamus.

Front 111

Osmoreceptors

Back 111

Located in the hypothalamus. Sensitive to osmotic pressure. Measures concentration of substances in the blood plasma.

Front 112

Touch receptors

Back 112

Mostly found in skin. Many different types. Some are close to the surface of the skin, very sensitive and in great concentrations in the fingers, lips etc.

Front 113

Pain receptors (a.k.a nociceptors)

Back 113

Stimulated by damage to tissues or excessive exposure to heat or chemicals. Concentrated in skin and mucous membranes. Occur in most organs but not the brain. Pain warms us something is wrong in the body such as tissue damage.

Front 114

Reflexes

Back 114

A rapid, automatic response to a change in the external or internal environment.

Always is:

stimulus, involuntary, rapid and stereptyped.

Front 115

Spinal reflex

Back 115

...

Front 116

Reflex arc

Back 116

Pathway of nerve impulse from receptor to effector.