1. Endocrine System Notes

2. THE ENDOCRINE SYSTEM (pp. 997 - 1008)
There are two systems that regulate the body. The nervous system relays information to the body using ___ _________________________ that travel very _______, but the messages are short- lived. The endocrine system uses _________________, or _________________ messages that travel through the _________ to relay information to the body..
Electrical system
fast
hormones
chemicals
blood

3. THE ENDOCRINE SYSTEM
The endocrine system is slower-acting, but the action of hormones is _______________________. The ____________________, which maintains homeostasis in the body, controls most of the glands of the endocrine system.
Longer lasting
hypothalamus

5. I. ENDOCRINE GLAND FUNCTION
A. Hormone Production
Hormones help regulate growth, metabolism, appearance, behavior, growth, reproduction,
and fluid balance. Most hormones are produced by _______________ glands.
endocrine

6. ENDOCRINE GLAND FUNCTION
Endocrine glands are unique because they are ductless; in other words, hormones are secreted into ____________________ and the _____________________ system transports the hormone to its destination. Its destination is known as its ______________. A hormone may have only one target, or it may have several.
the blood
circulatory
target

7. ENDOCRINE GLAND FUNCTION
B. Control of Hormone Production
Hormone release is regulated by a mechanism known as ____________________________.
Information about the effect of the hormone is “fed back” to the gland. When the desired condition is reached, the gland ________________________________________
Negative feedback
Switches off

8. NEGATIVE FEEDBACK SYSTEM

9. TYPES OF HORMONES
C. Types of Hormones – Hormones can be placed in two groups based on chemical structure:
1. Peptide hormones – Most hormones are composed of _________________ and are
known as peptide hormones.
2. Steroids – _____________ molecules derived from _____________________. Include the sex hormones - ________________________________
proteins
Lipid
cholesterol
testosterone & estrogen

11. Growth Hormone Insulin Glucagon
GLAND
EFFECT
Growth Hormone
Pituitary Gland
Stimulates _mitosis_; undersecretion results in _dwarfism__; oversecretion results in _gigantism_
Thyroxine
Thyroid
Regulates __metabolism____; requires _iodine___ for normal function
Insulin
Pancreas
_Lowers________ blood _glucose___ concentration by stimulating cells to take up glucose; triggers storage of glucose as _glycogen______; not produced in individuals with _Type I Diabetes_____
Glucagon
__Increases______ blood glucose concentration by breaking down _glycogen_______ stored in liver to glucose

12. Epinephrine
(_Adrenaline_)
Adrenal Glands
Known as _”fight or flight”________ hormone
_Bronchioles___ dilate to increase air flow for _cellular respiration_____
_Glycogen_____ in the liver is broken down to glucose for _cellular respiration____
_Heart___ rate is increased
Blood flow to the _skeletal__ muscles increases
Blood flow to the _digestive____ system is decreased

13. Testosterone
Testes
Triggers development of secondary sex characteristics; _meiosis_____ to produce __haploid____ sperm cells.
Estrogen/Progesterone
Ovaries
Triggers development of secondary sex characteristics; __meiosis______ to produce __haploid_____ egg cells.

14. Reproductive System

15. Function:
The purpose of the reproductive system is to produce _gametes_ and allow for _fertilization_ to take place. Although a healthy reproductive system is not a requirement for an individual _organism, it is essential for continuation of a _species.

16. Male Reproductive System
Scrotum – Contains testes; allows for _lower temperature needed for sperm production
Testes – Site of _gamete_ production. Specialized _diploid (2n) cells undergo _meiosis_ to produce _haploid (n) sperm cells.
Meiosis begins at _puberty and continues until _death
Each meiotic division produces 4 sperm cells with 23 chromosomes

17. Male Reproductive System
Scrotum – Contains testes; allows for _lower temperature needed for sperm production
Testes – Site of _gamete_ production. Specialized _diploid (2n) cells undergo _meiosis_ to produce _haploid (n) sperm cells.
Meiosis begins at _puberty and continues until _death
Each meiotic division produces 4 sperm cells with 23 chromosomes

18. Epididymis- sperm mature & are stored
Vas Deferens – Tubes that transport sperm to _urethra.
Glands
Prostate Gland and Seminal Vesicles – Produce _semen to provide _nutrients, protect sperm from acidic vagina
Bulbourethral Gland – Produces acid neutralizer to protect sperm from any residual _urine_____ in urethra
Penis – Means for sperm delivery via _urethra during _ejaculation_

19. Female Reproductive System
The female reproductive system is designed for _gamete production and development of the _embryo_ following fertilization.

20. Female Reproductive System
Ovary – Site of meiosis and gamete production; however there are three ways oogenesis differs from spermatogenesis:
Meiosis begins _before birth, but it is paused until puberty so females are born with total set of immature egg cells. During the female menstrual cycle, one egg cell or _ovum__ completes meiosis.
Meiosis stops when a female is years old. Known as _menopause; menstruation ceases
Meiosis produces only _one_ egg cell. The other 3 cells disintegrate so that the single egg cell contains all the _cytoplasm.

21. Female Reproductive system
Oviducts – Also known as the _fallopian tubes____. Passageway for egg cell during ovulation. Site of _fertilization__. When sperm and egg cell fuse, a _diploid____ _zygote___ is created with _46__ chromosomes. Development of the zygote to an _embryo____ → _fetus____ → _baby__ is carried out through _mitosis

23. Female reproductive system
Uterus – Site of _embryo development.
Implantation takes place approximately 5-7 days following fertilization.
If fertilization does not occur, lining of uterus is sloughed off during _menstruation____.
Vagina – Also known as “_birth canal”; passageway for _sperm_ in and _baby_ out