Related Concept Videos

Crossing Over01:34

Crossing Over

Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...
Crossing Over01:30

Crossing Over

Crossing over is the exchange of genetic information between homologous chromosomes during prophase I of meiosis I. Genetic recombination gives rise to allelic diversity in the newly formed daughter cells. In humans, crossing over produces genetically distinct haploid egg and sperm cells that undergo fertilization to produce unique offspring. Before cell division starts, the germ cell’s chromosome(s) undergo duplication in the S phase of the cell cycle. As the cells enter prophase I, duplicated...
Crossing over01:34

Crossing over

Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...
Uterine Tubes01:16

Uterine Tubes

The uterine or fallopian tubes function as the conduit through which oocytes travel from the ovaries to the uterus. Each fallopian tube measures approximately 10 to 13 cm long and is anatomically divided into the infundibulum, ampulla, isthmus, and interstitial part (or intramural segment). The infundibulum is characterized by its funnel shape and features extensions called fimbriae which reach towards the peritoneal cavity. These fimbriae play a critical role during ovulation as they extend...
Overview of Cell-Matrix Interactions01:24

Overview of Cell-Matrix Interactions

The extracellular matrix or ECM holds cells together to form a tissue and allows the cells within the tissue to communicate. ECM comprises proteins such as fibronectin, collagen, laminin, etc. The most abundant protein in this space is collagen. Collagen fibers are interwoven with carbohydrate-containing protein molecules called proteoglycans. ECM allows cell migration and provides a structural scaffold at cell adhesion that anchors the cell when the extracellular matrix proteins interact with...
Histology of the Uterus01:19

Histology of the Uterus

The uterine wall consists of three histological layers: the perimetrium, myometrium, and endometrium. The outermost perimetrium is a thin, serous membrane connected with the broad ligament on the sides, which helps anchor the uterus in the pelvic cavity. The thickest layer, myometrium, is mainly made up of smooth muscle tissue bundles. Its contractions are vital in facilitating the expulsion of the uterine lining, fetus, and placenta during menstruation and childbirth.
The endometrium is the...