By Darth Benjamanus

Signals in Animals

Hormones: Chemical signals that convey information between organs

Pheromones: chemical signals between different individuals

EX: Mating attractions

HORMONES Only target cells receive

message They elicit a specific

response Over 50 known hormones

in the human body Steroid hormones

(including sex hormones) are lipid molecules the body makes from cholesterol

Bind to specific protein receptors inside pm

Non-steroid hormones bind to specific receptors outside plasma membrane

Hormones Bind to Specific Receptors!

Hormones act at very low concentrations

Signal transduction pathway: sequence of steps that enable a hormone to produce an intracellular change

Steroid receptors are specialized proteins within the cells

Chemical signals are relayed and amplified by 2nd messengers and protein kinases

Earl W. Sutherland- pioneer for endocrine system, received Nobel prize 1971.

CAMP- Cyclic Adenosine Monophosphate

Signals Signal transduction involving cAMP: binding of a hormone to surface

receptor activates G protein (relay)

Activates anenylyl cyclase (effector) to produce cAMP,

Which activates cAMP-dependent protein kinase, enzyme that phosphorylates proteins

Invertebrate control systems integrate both endocrine and nervous system functions.

Diverse hormones regulate different aspects of homeostasis in invertebrates.

Hormones controlling reproduction and development have been extensively researched

Different job, different hormone.

Target Cells

Specific hormones target specific cells While one cell may be affected by a

hormone, its neighbors may remain untouched

(Target cell)

Pheromones (again)

Carry messages in between different individuals of a species, as in mate attraction

DARK MARK, YO!

Local Regulators Growth Factors: peptides and proteins

that stimulate cell proliferation Nitric Oxide: Highly reactive, triggers

changes in a target cell w/in a few seconds of contact and then breaks down;

Functions as a neurotransmitter, kills cancer cells relaxes muscles

Prostaglandins (PGs)- modified fatty acids Stimulate contractions in the

smooth muscles in the wall of the uterus, during both intercourse and labor

REGULATE THIS!!

Vertebrate Endocrine System

Hypothalamus

In brain, controls other glands

Like a boss!

Pituitary gland Promotes kidney water

retention Stimulates:

contraction of uterus and mammary gland cells

growth(especially bones) and metabolic functions

production of sperm/ova ovaries and testes thyroid gland adrenal cortex to secrete

glucocorticoids

I’m the boss!

Pituitary gland= the boss!

Parathyroid Glands:

Stimulate and maintain metabolic processes Lowers blood calcium level Thyroxin- Hormone that controls metabolism

Raise blood calcium level (homeostasis)

Thyroid Gland:

Pancreas

Insulin: Lowers blood glucose level Glucagon: Raises blood glucose level

Adrenal Glands Raise blood glucose

level Increase metabolic

activities Constrict certain blood

vessels Promote re-absorption

of sodium and excretion of potassium in kidneys

Epinephrine or norepinephrine

Fight or Flight!!

Testes Secrete Testosterone Support sperm formation Promote development and

maintenance of male secondary sex characteristics

Ovaries Secrete Estrogen Stimulate uterine lining

growth Promote development and

maintenance of female secondary sex characteristics

(Gonads)

Pineal Gland

Secretes MelatoninInvolved in Biological Rhythms

Thymus Gland

Stimulates T Lymphocytes

NOW GET OUT THERE, AND PUNCH THAT TEST IN THE FACE!!!

Who’s your DADDY???

This has been…..

a Darth Benjamanus Production