Temperature, Tropism, Taxis, and Food Webs in Ecosystems
Temperature: Definition and Significance
Temperature is a physical quantity that expresses the degree of hotness or coldness of a substance. Generally, a hotter object will have a higher temperature. Physically, it is a scalar quantity related to the internal energy of a thermodynamic system. More specifically, it is directly related to the internal energy known as “sensitive energy,” which is the energy associated with the movement of particles in the system, whether in a translational, rotational,
Read MoreNervous System: Receptors, Neurons, and Synapses
Receptors
Receptors are sensory cells that detect internal or external stimuli and convert one form of energy into electrochemical energy.
Coordinators
Coordinators are part of the Central Nervous System (CNS), which includes the brain and spinal cord. They process the information received from receptors and initiate an appropriate response by communicating with effectors.
Effectors
Effectors are muscles or glands that bring about a response.
Peripheral Nervous System
The Peripheral Nervous System consists
Read MorePlant Pathogens: Fungi, Bacteria, Viruses & Soil Treatments
Plant Pathogens Affecting Crops
Fungi Affecting Roots
- Fusarium proliferatum: Affects asparagus.
- Rhizoctonia solani
- Sclerotinia sclerotiorum: Affects artichokes, sensitivity to pig slurry N.
- Phytophthora cactorum: Affects strawberries and carrots.
- New pathogen: Fusarium oxysporum in Spain (report to authorities).
Fungi and Bacteria Affecting Vascular System
- Fusarium oxysporum fsp cyclaminis: Affects cyclamen in Madrid.
- F. oxysporum fsp dianthi: Affects carnation in Almeria, related to sheep manure.
- Fusarium
Digestive Process in Vertebrates: Stages and Functions
Digestive Process – Stages
- Ingestion: Food enters the organism. In most animals, food enters through the mouth.
- Digestion: Transforms food into the simplest molecules that can be used by cells. In most animals, food undergoes a double transformation: mechanical and chemical.
- Absorption: The molecules obtained during digestion pass through the walls of the digestive tract to be incorporated into all cells of the organism.
- Egestion: The process of eliminating all food waste that could not be digested
Molecular Biology: DNA to Protein Synthesis
DNA Replication, Transcription, and Translation
DNA Replication
- The DNA double helix unwinds.
- Topoisomerases prevent supercoiling.
- Single-strand binding proteins (SSB) stabilize the separated DNA strands.
- Replication forks are bidirectional, with a helicase at each fork.
- Primase synthesizes an RNA primer, as DNA polymerase cannot initiate synthesis without one.
- DNA polymerase begins synthesis from the primer in the 5′ to 3′ direction on the leading strand.
- On the lagging strand, RNA polymerase synthesizes
Cellular Biology: Types, Structures, and Functions
What name receives red blood cells? Erythrocytes.
Immature forms of red blood cells with RER are called: Reticulocytes.
Agranulocytes or mononuclear cells are: Lymphocytes and monocytes.
Thrombocytes originate from cells called: Megakaryoblasts and megakaryocytes.
Approximately how many different cell types are in the body? About 200 types.
The serous cavities are lined by a tissue called: Mesothelium.
What epithelial tissue is observed in absorptive function? Endothelium.
The face of a polyhedral epithelial
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