The document discusses homeostasis and the endocrine and nervous systems' roles in maintaining internal balance in the body. It explains that homeostasis involves keeping internal conditions stable through negative feedback loops even when the external environment changes. The nervous system controls body functions through nerve signals, while the endocrine system uses hormones as chemical signals released by glands to coordinate whole-body functions. Key glands discussed include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes. Hormones trigger changes in distant target cells and regulate processes like growth, development, metabolism, and reproduction through feedback loops.
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The document discusses homeostasis and the endocrine and nervous systems' roles in maintaining internal balance in the body. It explains that homeostasis involves keeping internal conditions stable through negative feedback loops even when the external environment changes. The nervous system controls body functions through nerve signals, while the endocrine system uses hormones as chemical signals released by glands to coordinate whole-body functions. Key glands discussed include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes. Hormones trigger changes in distant target cells and regulate processes like growth, development, metabolism, and reproduction through feedback loops.
The document discusses homeostasis and the endocrine and nervous systems' roles in maintaining internal balance in the body. It explains that homeostasis involves keeping internal conditions stable through negative feedback loops even when the external environment changes. The nervous system controls body functions through nerve signals, while the endocrine system uses hormones as chemical signals released by glands to coordinate whole-body functions. Key glands discussed include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes. Hormones trigger changes in distant target cells and regulate processes like growth, development, metabolism, and reproduction through feedback loops.
Copyright:
Attribution Non-Commercial (BY-NC)
Available Formats
Download as PPT, PDF, TXT or read online from Scribd
The document discusses homeostasis and the endocrine and nervous systems' roles in maintaining internal balance in the body. It explains that homeostasis involves keeping internal conditions stable through negative feedback loops even when the external environment changes. The nervous system controls body functions through nerve signals, while the endocrine system uses hormones as chemical signals released by glands to coordinate whole-body functions. Key glands discussed include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes. Hormones trigger changes in distant target cells and regulate processes like growth, development, metabolism, and reproduction through feedback loops.
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Endocrine System Hormones & Homeostasis
AP Biology
2006-2007
Homeostasis
Homeostasis
maintaining internal balance in the body
organism must keep internal conditions stable even if environment changes also called dynamic equilibrium humans: too cold = shiver too warm = sweat
example: body temperature
lizard: too cold = bask in sun too warm = hide in shade
Regents Biology
Regulation
How we maintain homeostasis
nervous system
nerve signals control body functions
endocrine system
hormones chemical signals control body functions
Regents Biology
Nervous System Control Feedback Controlling Body Temperature
Maintaining homeostasis hormone 1 lowers body condition gland
high specific body condition
low raises body condition gland
Regents Biology
hormone 2
Negative Feedback
Response to changed body condition
if body is high or low from normal level
signal tells body to make changes that will bring body back to normal level hormone 1 lowers body condition
once body is back to normal level, signal is turned off gland
high
Regents Biology
specific body condition
Endocrine System Control Regulation of Blood Sugar
insulin body cells take up sugar from blood
Feedback
liver stores sugar
reduces appetite
pancreas
high blood sugar level (90mg/100ml)
liver
low triggers hunger liver releases sugar
pancreas
Regents Biology
liver
glucagon
Everyones doing it, so Ask Questions!!
AP Biology
2006-2007
Sex & Growth Hormones
Large scale body changes
how do they work
turn genes on start new processes in the body by turning genes on that were lying dormant
Regents Biology
Pituitary gland hormones
Sex & reproductive hormones
FSH
follicle stimulating hormone stimulates egg & sperm production luteinizing hormone stimulates ovaries & testes prepares uterus for fertilized egg stimulates childbirth contractions releases milk in nursing mothers hormones hormones
LH
oxytocin
prolactin
milk production in nursing mothers
Regents Biology
Reproductive hormones
Testosterone
from testes sperm production & secondary sexual characteristics from ovaries egg production, preparing uterus for fertilized egg & secondary sexual characteristics
Estrogen
Regents Biology
Male reproductive system
Sperm production
over 100 million produced per day! Regents Biology ~2.5 million released per drop!
seminiferous tubule
sperm
spermatocytes Regents Biology
Male reproductive system
Testes & epididymis
sperm production & maturation
Glands seminal vesicles, prostate, bulbourethal produce seminal fluid
nutrient-rich
Regents Biology
Male reproductive system
Testicles
produces sperm & hormones sac that holds testicles outside of body where sperm mature tubes for sperm to travel from testes to penis
produces eggs & hormones nurtures fetus; lining builds up each month tubes for eggs to travel from ovaries to uterus opening to uterus, dilates 10 cm for birthing baby birth canal for birthing baby
Uterus
Fallopian tubes
Cervix
Vagina
Regents Biology
Female reproductive system
Regents Biology
Egg maturation in ovary
releases progesterone
maintains uterus lining
Regents Biology
produces estrogen
Menstrual cycle
LH FSH
Controlled by interaction of 4 hormones egg development
FSH & LH estrogen progesterone
ovulation = egg release
corpus luteum
estrogen
progesterone lining of uterus
Regents Biology
days 0
14
21
28
Feedback
Female reproductive cycle
estrogen ovary egg matures & is released (ovulation) builds up uterus lining corpus luteum
progesterone FSH & LH
maintains uterus lining fertilized egg (zygote)
HCG
pituitary gland
yes pregnancy GnRH
corpus luteum
no corpus luteum breaks down progesterone drops menstruation
progesterone maintains uterus lining
Regents Biology hypothalamus
Female hormones
FSH & LH
released from pituitary stimulates egg development & hormone release peak release = release of egg (ovulation)
Estrogen
released from ovary cells around developing egg stimulates growth of lining of uterus decreasing levels causes menstruation
Progesterone
released from corpus luteum in ovaries cells that used to take care of developing egg stimulates blood supply to lining of uterus decreasing levels causes menstruation Regents Biology
Fertilization
Regents Biology
Any Questions??
AP Biology
2006-2007
What do they do?
Body Temperature
Maintain homeostasis blood sugar level temperature control
Start a new process
growth fetal development sexual development
Regents Biology
Negative Feedback
Negative feedback
every time body is high or low from normal level a signal tells the body to make changes that will bring body back
body temperature control of blood sugar
Regents Biology
Regulation by chemical messengers
Neurotransmitters released by neurons Hormones release by endocrine glands
endocrine gland neurotransmitter
axon hormone carried by blood
receptor proteins
receptor proteins
Regents Biology
target cell
Body Regulation
Nervous system & Endocrine system work together
hypothalamus
master nerve control center receives information from nerves around body about internal conditions
communicates with pituitary gland
master gland releases many hormones hormones sexual development, growth,
