Plant Reproduction: Asexual and Sexual Methods
Plant Reproduction: Asexual and Sexual Methods
The Diplohaplontic Cycle
The diplohaplontic cycle is the cycle that characterizes plants with alternating generations: a diploid sporophyte and a haploid gametophyte.
The sporophyte undergoes meiosis to form haploid spores. These spores germinate and give rise to haploid gametophytes, which produce gametes by mitosis. The gametes fuse, forming a diploid zygote that divides to form a diploid sporophyte.
Types of Reproduction in Plants
Plants have two basic
Read MoreMicrobial Control and Sterilization Techniques
Sterilization and Microbial Control
Sterilization – a process that destroys or removes all viable microorganisms, including viruses.
Sterile – any material that has been subjected to sterilization.
Bactericide – chemical that destroys bacteria except for those in the endospore stage.
Fungicide – chemical that can kill fungal spores, hyphae, and yeasts.
Virucide – chemical known to inactivate viruses, especially on living tissues.
Sporicidal agent – destroys bacterial endospores.
Microbistasis
Read MoreHuman Eye Anatomy and Physiology: A Comprehensive Look
**Cornea**
The cornea has no blood vessels. It is transparent due to the layer of cells above the eye. It is formed preferentially by epithelial carcinoma (there are more, but this is the most abundant). To the front is a layer that protects the related tear, and to the back, we find the aqueous humor. It is the first lens of the optical system. It transmits light and is responsible for refraction (the deviation of light when it passes from one medium to another). It is also a physical barrier against
Read MoreCell Division, Reproduction, and Nucleic Acids
Cell Division
Transmission gives information to do so. This occurs when a DNA cell multiplies during cell division. A cell divides and gives rise to two daughter cells with the same genetic information as the progenitor. This occurs during the process of sexual reproduction when gametes unite and give rise to a new zygote, inheriting characteristics from both progenitors.
Propagation of cell characteristics: A progenitor cell divides and distributes its content between two daughter cells. But before
Read MoreGenetic Engineering: Techniques and Applications
DNA Fragmentation
Fragmentation of DNA: Enzymes capable of breaking the DNA are called restriction endonucleases, restrictases, or restriction enzymes. They are able to recognize and cut at specific points in the sequence of nucleotides, which are called target sequences.
Use of a Vector
A vector is responsible for introducing a particular piece of DNA into other cells.
Plasmids
Bacteria possess a circular, double-stranded DNA molecule in which they carry most of their genetic information. But they also
Read MoreImmune System: Defenses, Responses, and Immunopathology
Concept of Immunity
Immunity is a set of mechanisms that an individual possesses to counter the invasion of any foreign body or to deal with tumors. This property is acquired before birth and matures and consolidates in the first years of life. In vertebrates, it implies that different agencies distinguish self from outside, i.e., recognize all cell types. The immune system is responsible for conferring immunity. This system, present even in invertebrates, reaches its greatest complexity in primates
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