Anatomy ch 11- Endocrine system
what are the 2 types of hormones?
Steroid and nonsteroid
What can get through without a carrier?
lipid
was the protein molecule present before the steroid hormone entered the cell, or was it made new?
made new- transcription translation
Where is the receptor for the steroid hormone located?
nucleus
what type of molecule is eventually produced as a result of the steroid hormone entering the cell?
protein
The second messenger actually delivers its message by activating what class of enzymes
protein kinase- catalyzes transfer of phosphate groups
what kind of cells can steroid hormones enter, and explain why steroid hormones typically have systematic targets
they can enter any cell because they are hydrophobic
What is ammonia?
NH3
What enzyme is activated when the hormone binds its receptor?
adenylate cyclase
Adenylate cyclase turns ATP into what?
cAMP (2nd messenger)
What is an amine group?
derivative of ammonia
what are some things that proteins are responsible for in human cells
everything we do is based on proteins. structure, catalyze
What is the word for water fearing? water loving?
fearing: hydrophobic loving: hydrophilic
Which of the 4 main classes of biological molecules makes up the inner portion of cell membranes?
lipid
Do lipids mix well with water?
no
Do non-steroid hormones cause the expression of new proteins like steroid hormones do?
no, they activate an existing protein
Cyclic AMP (cAMP) is known as the second messenger because it actually delivers the hormone's signal to the cell cytoplasm. What delivered the message to the cell in the first place?
non-steroid hormone
What are prostaglandins?
non-steroid hormones but get their own category because they are local, therefore they are not considered hormone-like
where is the receptor for the non-steroid hormone located?
on the cell surface
What process does the hormone-receptor complex initiate in the nucleus of the cell?
transcription- process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). The newly formed mRNA copies of the gene then serve as blueprints for protein synthesis during the process of translation.
Describe the endocrine system and what it does
- it works with the nervous system to maintain homeostasis -it is made up of cells, tissues, and organs that secrete hormones to act on target cells
What are 2 types of secretions?
- paracrine: only affects neighboring cells -autocrine: only affects itself
What is the sequence of events for non-steroid hormones?
1) Hormone binds to a receptor 2) G protein is activated 3) Adenylate cyclase molecules are activated inside the cell 4) ATP is converted into cAMP 5) Protein kinases are activated 6) Substances inside the cell are activated, resulting in production of the hormone's effects
What is the sequence of events for steroid hormones?
1) Steroid hormone diffuses through the cell membrane 2) Hormone binds to receptor 3) Hormone-receptor complex binds to DNA 4) transcription of DNA 5) mRNA enters cytoplasm and directs protein synthesis 6) new proteins produce the steroid hormone's effects
Explain the control of the endocrine system
1) hypothalamus and anterior pituitary stimulate other glands 2) nervous system can stimulate gland directly 3) changes of level of a substance can stimulate glands directly