Animal and Plant Nutrition: Processes and Adaptations
Nutrition
Nutrition describes the processes by which living things take in external substances and turn them into matter and energy.
Autotrophs
Autotrophs produce their own organic matter from inorganic substances taken from the environment. They can be:
- Photosynthetic: Obtain energy from sunlight.
- Chemosynthetic: Obtain energy from chemical reactions.
Heterotrophs
Heterotrophs feed on other organisms or their remains. They can be carnivores, herbivores, omnivores, filter feeders, scavengers, etc.
Processes
Read MoreEnzyme Reactions and DNA/RNA Structure: A Detailed Analysis
Enzyme Reactions: Key Processes in Metabolism
Enzyme reactions are chemical conjugates in metabolism, involving very low concentrations and accelerating reactions involved with decreasing activation energy. They are water-soluble globular proteins that are well in the diffusion of organic liquids. They can act at intracellular and extracellular levels (where they are secreted).
Chemical Nature
Enzymes can be shaped by one or more polypeptide chains, denominated solely as protein enzymes, or a part
Read MoreEvidence and Mechanisms of Biological Evolution
Evidence of Evolution
Biological evolution is possibly the most important process that affects all living creatures on Earth. This process does not shine directly on certain living beings, since it is a process that lasts a long time and takes thousands or millions of years to manifest. Nevertheless, it is an unstoppable process that began with the appearance of life and, since then, has lost none of its vigor. We can be more certain of the existence of this process in the past because, as we just
Read MorePlant 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
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