Enzymes, Metabolism, and Cellular Energy Processes
Enzymes: Biological Catalysts
Cells possess chemical compounds that control internal reactions. Enzymes are proteins acting as catalysts, accelerating chemical reactions without harming the cell. Each enzyme acts on a specific substrate. Enzyme names often end with the suffix -ase (e.g., maltase, lactase).
Denaturing Proteins: High temperatures break molecular links in proteins.
Metabolic Pathways
Metabolism types include:
- Photolithotrophs: Light energy, CO2 (plants, algae, cyanobacteria).
- Photoorganotrophs:
Understanding Fungi: Structure, Function, and Infections
Mushrooms
Characteristics
Fungi are eukaryotic cells without chlorophyll and chloroplasts. They are heterotrophic organisms, forming their own kingdom. Fungi can be microscopic or macroscopic and are found in various environments, including soil, water, plant and animal remains, and living organisms as parasites.
Structure
Fungi have two main structural types:
- Levuriforme (Yeast): Unicellular.
- Mycelial: Multicellular.
Yeast
Yeasts are unicellular organisms with typical eukaryotic organelles. They often
Read MoreCell Division: Mitosis and Meiosis Processes
Mitosis
Cell division involves two sequential processes: mitosis (nuclear division) followed by cytokinesis (cytoplasm division). In mitosis, genetic material is equally distributed, ensuring each daughter cell receives identical information. Chromosome division occurs during the S phase.
Mitosis phases:
- Prophase: Nuclear envelope and nucleolus disappear. Chromatin condenses into visible chromosomes, each with two chromatids joined at the centromere. The spindle forms. In animal cells, centrioles duplicate,
Human Biology: Metabolism, Respiration, and Circulation
Metabolism
Metabolism encompasses all the chemical processes within a living organism. It’s broadly divided into two categories:
- Anabolism: The synthesis or construction of matter.
- Catabolism: The degradation of matter.
Gas Exchange
Gas exchange occurs in the lungs, specifically within the alveoli. Oxygen from the air diffuses into the blood, while carbon dioxide diffuses from the blood into the air. This exchange is driven by simple diffusion. Pulmonary ventilation, the process of air entering and exiting
Read MoreEndocrine System Overview: Glands, Hormones, and Functions
Endocrine System Overview
Hypothalamus
Located in the brain below the thalamus, the hypothalamus acts as the main integration center between the nervous and endocrine systems. It controls the autonomic nervous system and regulates vital functions such as body temperature, thirst, hunger, and emotional responses like fear and anger.
Pituitary Gland
A pea-sized structure (1.5 cm in diameter) situated in the sella turcica of the sphenoid bone, the pituitary gland connects to the hypothalamus via the infundibulum.
Read MoreKidney Structure and Function
Renal Structure
The kidneys are bean-shaped organs located in the back of the abdomen, behind the peritoneum, on each side of the spinal column. They measure about 12 x 6 x 3 cm and weigh between 130 and 150 g. The final product is urine, excreted through the urinary system.
Urine produced by the kidneys is collected in the renal pelvis, flows through the ureters into the bladder, and exits through the urethra.
The functional unit is the nephron. Each kidney contains 600,000 to >1,000,000 nephrons.
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