The Life Cycle of Chara, a Fresh Water Green Alga

Audrey Hamm

0:00

Animation

Description

This animated short film is a look at the life history of Chara, a close relative of embryophytes (land plants). A life history is the series of growing and reproductive changes an organism undergoes throughout its life. Chara is a genus in the fresh water green algal family Characeae, commonly called stoneworts or musk grasses. For this video, the morphology of Chara rusbyana was studied by using a living culture and by consulting the botanical literature. A key difference between the life history of land plants and the Characeae is that alternation of generations is found in land plants but not in the Characeae. Given that the Characeae are close relatives of land plants, understanding their life history is valuable to our ever-broadening knowledge of the early evolution of land plants.

Language

English

Voice Age

Young Adult (18-35)

Accents

North American (General)

Transcript

Note: Transcripts are generated using speech recognition software and may contain errors.
in this freshwater pond, a close cousin of land plants is about to begin its life cycle. It is in the family of algae called the Cory. See. We will begin with the psycho Spore. A dormant Saigo deposited here by its mother plan to the previous year. Single cell within contained starchy nutrients from its mother that feeds it's infantile growth before dividing even ones deployed Saigo undergoes my oh sis Or so we think as this has yet to be confirmed, humans are deployed. My oh sis occurs before fertilisation in order to create Hap Lloyd Gam eats from are deployed genome forming a deployed sigh goat that then undergoes my toe Sis care of Rose Bianna is Hap Lloyd My oh sis occurs after fertilization in order to create its half blow genome from a deployed zygote formed by Hap Lloyd gametes that were created by my toe sis. Either way, this mixes the parents genomes and creates completely new gene combinations in the offspring. The evolutionary benefit of sexual reproduction. What emerges from the top of the sport coat is a single hap Lloyd cell. At its first division, the larger cell becomes the root like rise, oId and the smaller sell the green photosynthetic filament. The green filament bulges and first grows a whirl of five. Simple branch lets the apex continues to grow until another world appears with yet another contained within it and another and another. After the first world of five branch, let's. Most of the plant body is covered by rows of cells, forming a protective cortex. Eventually, some notes will grow axillary buds that become new APIs ease and branch off of the main plant body. Some Khoury see, such as this character's Bianna, grow more adventurous branches that extend centimeters from the plant. Thes grove easy and branches propagate the plant way. Over the course of the season, the algo well establishes itself. Our plant happens to be a male. Fortunately, a female seems to be growing nearby, and by now they have grown near enough to have sex. Way no. Our plant is male by its orange sperm producing organs called anther idea. Inside of this anther idiom, filaments of cells propagate Bye bye toe sis. There cytoplasm becoming sperm which swim free upon maturity. Eight. Scoop themselves than open to release the batch into the water. Female alga has also been busy growing its egg cell structures. The logo Nia, the Ogoni um, consists of a large excel surrounded by five twisted cortex cells and five tips cells. At the top entrance, a single sperm finds its way to the top of the Ogoni um, where it swims into fertilized the egg, creating a deployed zygote. The Ogoni um store starch around the zygote, informs a calcified shell for protection. Zegas board then falls from the mother plant to the pond floor awaiting spring. It will then undergo my, Oh sis to mix its parents jeans and keep one of the four mixed copies for itself and re populate this pond once again in the spring.