Human Body Systems: Nutrition and Respiration
Devices Involved in Nutrition
The following systems are involved in human nutrition:
- Digestive system: Digests food and converts it into simpler substances.
- Respiratory system: Provides for the exchange of gases, providing O2 and clearing CO2.
- Circulatory system: Transports oxygen and usable food substances to different cells through the blood.
- Excretory system: Eliminates waste substances from the blood.
Digestive System
The digestive system includes:
- Intestinal tract: Made up of the mouth, esophagus,
Fundamental Concepts in Biology
Two Basic Types of Science
Science can be broadly categorized into two main types:
- Discovery Science: This type of science is primarily based on observation and data analysis. It involves describing the natural world through verifiable data.
- Example: Jane Goodall’s decades-long observation of chimpanzees in their natural habitat.
- Hypothesis-Driven Science: This approach involves formulating a tentative answer to a well-framed question (a hypothesis) and then testing predictions through experiments.
- Example:
Cellular Organelles: Structure and Function
Golgi Apparatus
Functions:
- Finalizes the protein glycosylation process underway in the Rough Endoplasmic Reticulum (RER). This process occurs sequentially from the cis face to the trans face of each dictyosome.
- Synthesizes glycolipids and sphingomyelins.
- Synthesizes complex polysaccharides of the cell wall in plant cells, which will be transported in vesicles for distribution and export.
- Directs proteins.
- Forms the acrosome in spermatozoa.
Chloroplast
Functions:
- Photosynthesis
- Fatty acid biosynthesis
- Reduction
Understanding the Characteristics of Life and Biomolecules
Living Features and Essential Biomolecules
Living Features:
The characteristics of life include: structure, metabolism, growth, adaptation, irritability, reproduction, organization, and homeostasis.
Metabolism:
Metabolism is the sum of all chemical processes in an organism. It is divided into:
- Anabolism: Synthesis or construction of molecules.
- Catabolism: Degradation of molecules.
Reproduction:
Reproduction ensures the continuation of species.
Evolution and Homeostasis:
Evolution is driven by environmental
Read MoreMollusks: Classes, Characteristics, and Importance
There are three main classes of mollusks: Gastropoda, Bivalvia, and Cephalopoda.
Gastropoda
Gastropoda includes snails, slugs, and abalones. The name means “stomach foot.”
- Movement: They use their foot to slowly crawl.
Bivalvia
Bivalvia includes clams, oysters, scallops, and mussels. They have two shells.
- Movement: They are often sessile, anchored in place for filter feeding. Some can use their foot to dig through the sand.
Cephalopoda
Cephalopoda includes octopi, squid, and cuttlefish. The name means “
Read MoreCell Electric Potentials: Principles, Mechanisms, Applications
Electric Potentials Generated by Cells: Principles, Mechanisms, and Applications
The electric potentials generated by cells are fundamental to the functioning of the human body and all living organisms. These electrical signals govern many physiological processes, including nerve transmission, muscle contraction, and the function of the heart. Understanding the generation and function of electric potentials in cells is critical for comprehending how cells communicate with each other and how the body
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