Search results
Results From The WOW.Com Content Network
Antheridia consist of a thin cellular layer that holds many sperm inside. Here, the diagram of a liverwort antheridium is shown. An antheridium is a haploid structure or organ producing and containing male gametes (called antherozoids or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an ...
The antheridia (male reproductive structure) are at the apex of the male gametophyte in a cup-like structure formed by perigonial leaves which are modified stem leaves. [11] Sperm is produced in the antheridia via mitosis, and when mature they are released from the antheridia by raindrops splashing onto the cup. Sperm can be dispersed up to one ...
Structure of a plant cell. Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae.Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or ...
English: A simple diagram of a plant leaf cell, labelled with numbers. It shows the cytoplasm, nucleus, cell membrane, cell wall, mitochondria, permanent vacuole, and chloroplasts. Note going down the left the numbers are not sequential, this is to match the numbering on others in the series. Cytoplasm; Nucleus; Cell membrane; Mitochondrion ...
Sexual reproduction in flowering plants involves the union of the male and female germ cells, sperm and egg cells respectively. Pollen is produced in stamens and is carried to the pistil or carpel, which has the ovule at its base where fertilization can take place. Within each pollen grain is a male gametophyte, which consists of only three cells.
[11] [10] One of these cells is typically a germ cell and other cells may consist of a single tube cell which grows to form the pollen tube, sterile cells, and/or prothallial cells which are both vegetative cells without an essential reproductive function. [10] After pollination is successful, the male gametophyte continues to develop.
The gametophytes produce both motile sperm in the antheridia and egg cells in separate archegonia. After rains or when dew deposits a film of water, the motile sperm are splashed away from the antheridia, which are normally produced on the top side of the thallus, and swim in the film of water to the antheridia where they fertilize the egg.
Chloroplast DNA (cpDNA), also known as plastid DNA (ptDNA) is the DNA located in chloroplasts, which are photosynthetic organelles located within the cells of some eukaryotic organisms. Chloroplasts, like other types of plastid , contain a genome separate from that in the cell nucleus .