Biology Flashcards
(118 cards)
what is the purpose of chyme in the duodenum, and what is chyme
chyme is acidic, it made from HCl secretion from parietal cells, and contents within the stomach.
it activated release of enteropeptidase.
the presence of chyme would leads to release of brush border enzymes which would help digest some of the macromolecules contained within.
what hormone do the ovaries produce
estrogen
What is the relationship of ANP and blood pressure?
ANP decreases arterial blood pressure
outline the key concepts of the menstrual cycle
- Follicles mature during follicular phase (FSH, LH)
- LH surge at mid-cycle triggers ovulation
- ruptured follice becomes corpus luteum, which secretes estrogen and progestrone to build up lining for implantation, FSH and LH are inhibited
- if fertilization did not occuer CL dies, due to lack of LH, progesterone and estrogen levels decrease, LH and FSH begin to rise again
what is the function of efferent neurons ?
- they send information from the CNS to the peripheral organs
How does a thyroid hormone complete its mechanism of action?
It binds to a nuclear receptor then modifies the protein, it is poorly water soluble
compare steroid hormones and thyroid hormones
thyroid hormone is amino acid derived hormone, but acts as a lipid based hormone, lipophilic. It has the same pathway of a steroid hormone.
- steroid hormones can go into the cell by pass the plasma membrane, bind to receptors in the cytosol, and affect DNA transcription.
- for thyroid hormones they enter the cell through a receptor, but don’t do a cascade they enter directly to the nucleus.
difference between lytic and lysogenic
Lyso- Long time, can remain dormant for years in the cycle
Lytic- short time, no regard for the host
which part of the sarcomere has organized bundles of myosin?
thick filaments are organized bundles of myosin
represented by the A band
how are single smooth muscle cells connected
- via gap junctions, the greater the strength of these connections, the more calcium ions can be spread between cells, and the stronger the contraction
Do T-tubules exist is smooth muscle cells
No
What secretes TRH and where does the TRH act on?
The hypothalamus secreted thyroid releasing hormone (TRH) and it acts on the AP
what gland releases TSH
Anterior pituitary, and TSH (peptide hormone) that acts on the thyroid
if heart rate is faster, describe the effect on the cardiac cycle
The cardiac cycle will be shorter, leading to a shorter diastole, this means the ventricles have less time to fill, leading to a lower stroke volume and therefore lower cardiac output.
what layers of the skin are burned off in a second degree burn
- dermis and epidermis
what are some structures and cell types located on the dermis
- Sweat glands
- Hair follicles
- Blood vessels
- afferent Nerve ending
what is keratin and where is it produced?
- Produced by keratinocytes in the stratum basale of the epidermis, keratin is a tough fibrous protein that migrates superficially with keratinocytes to the stratum corneum.
Where is the pharynx located and its function?
-resides behind the nasal cavity and back of the mouth, it is a common pathway for air and destined for the lungs and food destined for the esophagus
what are the functional components of the testes ?
Seminiferous tubules- sperm is produced here, and nourished by the sertoli cells
Interstitial cells of leydig
when the sperm is formed where is it stored
- it is stored in the epididymis, where flagella gain motility, and they are stored until ejaculation
-made in the testes
- during ejaculation, sperm travels through the vas deferens and enters the ejaculatory duct
what system is the NK cells part of?
- the innate immune system
Function of the lymphatic system
- provides pathway for fats to enter circulation
- return of fluids from tissues to circulatory system
- in the lymphatic system, cells of the innate immune system, like macrophages and dendritic cells can communicate with cells of the adaptive immune system, like B cells
- germinal center where B cells (not T cells) wait for their antigens, so then they build memory for reinfection
what type of cells are most effective in parasitic infections
-Eonsinophils, they release granules, that are effective against allergens and parasites
what is the subsection of the the nucleus that synthesizes ribosomal RNA
-Nucleolus