The Nervous System: A Comprehensive Analysis
The Nervous System
The nervous system is responsible for analyzing stimuli, both external and internal, and developing the necessary responses for the functioning of the body.
It can be distinguished into:
The Central Nervous System (CNS)
The CNS is in charge of body control and its activities.
The Peripheral Nervous System (PNS)
The PNS transmits nerve impulses from receptors to the CNS, and from the CNS to the effectors.
Central Nervous System
The central nervous system consists of the brain and
Read MoreAnimal and Plant Excretion: A Comprehensive Look
Excretion in Animals and Plants
Excretion in Animals
Excretion is the elimination of waste products resulting from cellular metabolism and is performed through urine, sweat, and breath. The excretory system carries out this process. Homeostasis consists of functions that enable organisms to balance their internal environment.
Waste Products in Animals
- Non-nitrogenous: CO2 and H2O. CO2 is eliminated through the respiratory surfaces, while water can be removed as a vapor by the same surfaces or in liquid
Cellular Biology: Tension-Cohesion, DNA, Reproduction, and Cellular Evolution
The Tension-Cohesion-Adhesion Hypothesis
Tension-Cohesion-Adhesion Hypothesis:
- Mesophyll cells lose water, creating a water deficit in the top floor, which results in negative pressure, also known as tension. The solute concentration in these cells increases, consequently increasing the osmotic pressure.
- Mesophyll cells become hypertonic in relation to the xylem, drawing water molecules into the cells.
- Water molecules are linked together due to cohesion forces (between water molecules) and adhesion
Fundamental Concepts in Genetics and Biology
Mendel’s Laws
- All individuals descended from the cross of two pure races are equal.
- To cross each other, the character of hybrids present in these are separated and are combined at random in the descendants.
- The various characters are inherited independently of one another and are combined at random in the offspring.
Cloning
Cloning, in scientific language, describes the obtaining of an individual identical to another. We call it a clone, i.e., with the same genome. Plants and animals, such as the sponge,
Read MoreDarwin’s Theory and Evolution: Key Concepts Explained
Darwin’s Theory and Evolution: Key Concepts
1) The Importance of Darwin’s Theory: Darwin’s major development theories aimed to prove that life emerged, deviating from lower to higher forms. With the passage of time, this evolutionary process became more complex, causing better-adapted individuals to exist. Animals and plant species inhabiting the Earth are subject to change, and it is through these changes that new forms of development originate.
2) Evolution: The process of continuous change over
Read MorePlant Processes: Respiration, Photosynthesis, and Nutrition
Key Functions of Plant Parts
Leaves
Leaves exchange gases with the environment through the stomata. Both respiration gases and photosynthesis gases, including water vapor, are expelled through perspiration. The leaves perform photosynthesis. Leaf cells have many chloroplasts, which are the organelles where the transformation of inorganic into organic substances takes place.
Stem
The stem carries crude sap through the xylem tubes and the elaborated sap through the phloem. It also performs other functions
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