Human A+P II: chapter 1

anatomy defintion

structure of body parts and their relations to each other

physiology definition

function of body parts and how they carry out activities

form is related to

function

atoms make up

molecules

molecules make up macromolecules or

cells

cells make up

tissues

tissues make up

organs

4 types of tissues

1. epithelial tissue

2. connective tissue

3. muscle tissue

4. nervous tissue

organs make up organ systems and systems make up

organisms

organ systems

11 organ systems

(ex. endocrine and nervous system)

Nervous and Endocrine Systems

control all other systems

nervous system

fast, short term effects

chemical messages like nerve impulses and neurotransmitters

endocrine systems

slower, long lasting

produces hormones that go straight into the bloodstream

ductless

endocrine system

hormones go directly into the bloodstream

endocrine glands hormones only act

on target cells that contain specific receptor for them

ducts

exocrine system

exocrine systems

(ducts)

does not produce hormones

deliever their products directly to a specific site (ex. salivary glands)

nervous system releases neurotransmitters into

synapses

hormones deliver messages by

binding to receptors

Steroid hormones (receptors inside the cell)

diffuse through the cell membrane and cause transcription of genes in DNA

Negative feedback

aids in homeostasis

hormone secretion is primarily controlled by

negative feedback (system/cycle turns off when goal is achieved)

homeostatic control variables include:

receptor

control center

effector

receptor

main sensor

monitors the environment

control center

integrating system

or “the brain”

receives input, determines, and signals the appropriate response

effector

receives output from control center

provides the mean to response

reduces or enhances stimuli by positive or negative feedback

enhances stimuli

positive feedback

reduces stimuli

negative feedback

An example of positive feedback is

childbirth

positive feedback

is a control mechanism in which rising levels of hormones leads to an increase in secretion

mainly in the reproductive system

childbirth positive feedback tells

the uterus to contract

negative feedback is the main method of

control in hormone secretion

pathway for hormones

hypothalamus, pituitary gland, other endocrine glands, + target cells/ organs

Hypothalamus def/ location

oversees homeostasis

in the brain

the hypothalamus links

the nervous and endocrine systems

Some hypothalamic neurons

synthesize/ make hormones directly

pituitary gland is attached to

the hypothalamus

hypothalamus ‘speaks’ to the pituitary gland

2 portions/ lobes of the pituitary gland

Adenohypophysis (anterior lobe)

Neurohypophysis (posterior lobe)

Anterior lobe

Adenohypophysis

Posterior lobe

Neurohypophysis

Pituitary Gland

each part releases certain hormones

Adenohypophysis regulation

anterior lobe

Hypothalamus tells the anterior pituitary gland what to release

anterior lobe

make and release hormones

Neurohypophysis regulation

posterior

hypothalamus makes the hormones while the neuro. releases the hormones

posterior lobe

temporary storage for hormones then are released

Major Anterior pituitary hormones

growth hormone, prolactin, thyroid stim. hormone, ACTH, FSH, lutinizing hormone

growth hormone (GH)

growing

stimulates the cells to enlarge and divide rapidly

Prolactin (PRL)

secretion of thyroid hormones T3 and T4 from thyroid glands

T3 and T4 controls

metabolism or metabolic rate in the body

type of thyroid hormones

Adrenocorticotropic Hormone (ACTH)

Follicle-stimulating hormone (FSH)

growth and development

stimulates the production of sperm (males) and egg (in females)

Luteinizing hormone (LH)

sex hormones production in both genders (testosterone + estrogen)

cause ovulation in females

Hypopituitary dwarfism

deficiency of gH in childhood

Giantism

large but poportional

caused by oversecretion of GH during childhood

growth hormone is being produced in excess

Acromegaly

nonporportional big hands, feet, nose, etc

caused by a oversecretion of GH during adulthood after epiphyseal ossification (officially stop growing)

Posterior Pituitary hormones

Antidiuretic hormone (ADH vasopressin)

Oxytocin

Antidiuretic hormone (ADH vasopressin)

decreases urine production by reducing volume of H2O to the kidneys excrete

helps retain water

Oxytocin

milk let down

causes muscle contraction in uterine wall during childbirth (hormone positive feedback)

Thyroid gland

produces 3 hormones T3,T4, and Calcitonin

T3 and T4 hormones

in thyroid gland

controls metabolism or metabolic rate

Calcitonin

reduces calcium levels in your blood

Clinical appl. of thyroid

Hyperthyroidism

Hypothyroidism

Hyperthyroidism

protruding eyes, higher metabolic rate, + weight loss

Hypothyroidism

goiter as a result of no iodide

deficiency of thyroid hormones (T3+T4) due to iodide deficiency

Parathyroid Gland

4 glands, releases PTH parathyroid hormone

PTH increases (regulates Ca+) blood levels of calcium and decrease phosphate

Calcitonin and PTH have

opposite effects

PTH- increases

Calcitonin- decreases