Renal Physiology and Oogenesis Review

Vocabulary practice flashcards covering glomerular filtration pressures, kidney regulation mechanisms, renal clinical conditions, and the stages of oogenesis.

HPG (Glomerular Hydrostatic Pressure)

The outward push of fluid out of the blood in the glomerulus related to blood pressure, which is approximately $60\text{ mmHg}$.

OBG (Blood Colloid Osmotic Pressure)

An inward pulling force of osmosis caused by the difference in solute concentration between the capillary and the capsule, measuring about $32\text{ mmHg}$.

Capsular Hydrostatic Pressure

The pushback or inward force caused by a buildup of fluid in the capsule around the capillaries.

Net Filtration Pressure

The total force calculated by taking the pushing out pressure minus the push/pull back in forces, which equals about $10\text{ mmHg}$.

GFR (Glomerular Filtration Rate)

The volume of filtrate formed per minute by the kidneys, averaging between $120\text{ to }125\,ml/min$.

Myogenic Response

An intrinsic renal autoregulation mechanism where smooth muscle cells in the afferent arteriole contract or relax to adjust blood flow in response to vessel stretch.

Macula Densa Cells

Cells in the juxtaglomerular apparatus located in the distal convoluted tubule that detect levels of sodium chloride in the filtrate.

Tubuloglomerular Feedback Mechanism

A secondary autoregulation system that uses feedback from macula densa cells to increase vasoconstriction when filtrate levels are too high.

Extrinsic Controls

Control mechanisms involving the nervous system and hormones that can override renal autoregulation to change GFR during stress or emergencies.

Mesangial Cells

Cells near the glomerular vessels that contract to decrease the filtration surface area or relax to increase it.

Renin

An enzyme released by the granular cells of the juxtaglomerular (JG) apparatus that starts the pathway to produce angiotensin II.

Angiotensin II

A hormone produced in response to renin that tells mesangial cells to contract, thereby decreasing the filtration surface area.

ANP (Atrial Natriuretic Peptide)

A hormone made by the heart atria that increases GFR by dilating the afferent arteriole and inhibiting the release of renin.

Anuria

Unusually low urinary output, defined as less than $50\,ml\text{ per day}$, often due to insufficient blood pressure or nephron damage.

Renal Failure

A condition where the GFR is less than $15\,ml/min$, preventing the kidneys from properly filtering waste and maintaining fluid balance.

Uremia

A condition resulting from kidney failure characterized by the accumulation of toxic molecules, ionic imbalances, and symptoms like fatigue or nausea.

Primary Oocytes

Diploid stem cells that begin meiosis during the fetal period and stall in prophase I until after puberty.

Secondary Oocyte

A haploid cell produced after the completion of meiosis I that receives the majority of the cytoplasm and nutrients needed for the egg.

Polar Body

A small, haploid 'waste cell' that contains half the genetic material during oogenesis but lacks the machinery and cytoplasm of the oocyte.

Dominant Follicle

The single follicle that survives the dip in follicle-stimulating hormone (FSH) to continue toward ovulation.

Luteinizing Hormone (LH)

A gonadotropin whose sudden spike and subsequent drop triggers the event of ovulation.

Follicle-Stimulating Hormone (FSH)

A hormone that stimulates the development and maturation of follicles in the ovaries.

Progesterone

A hormone produced by the corpus luteum that is responsible for maintaining the functional layer of the uterus.

Ovum

A diploid cell formed when a haploid secondary oocyte is fertilized by a haploid sperm and finishes meiosis.

Corpus Luteum

A structure formed from a ruptured follicle after ovulation that secretes progesterone.