Proteins, Enzymes, and Nucleic Acids
Proteins
Proteins are organic compounds composed of C, H, O, N, and S. They are large polymers made of smaller units called amino acids, which are joined by peptide bonds. The union of 1 to 12 amino acids gives rise to an oligopeptide, 12-100 forms a polypeptide, and more than 100, or if their molecular weight exceeds 5000 g/mol, constitutes a protein.
Biological Importance: Proteins are the most abundant organic compounds in cells. Their importance lies in the enormous quantity of functions they
Read MoreBacterial Cell Structures: Morphology and Functions
Living Preparations
Wet Mount
- Add a drop of the culture, and cover it with a glass slide.
- Benefits:
- It’s fast.
- Cells are alive, and you can see them in their natural shape.
- Can examine their behavior.
- Disadvantages:
- Hard to detect cells/characteristics.
- Covering the glass can damage larger cells, contaminate the observer’s fingers, dry out, and also become anoxic.
Staining
- Increases contrast and sometimes size.
- Before staining, we must let it dry and fix it. That way, the sample does not get washed off.
- Positive
Minerals, States of Matter, Kingdoms, and Species
Minerals, Liquids, Solids, Mixtures and More
Mineral: A naturally occurring substance, solid, that stems from a formula according to a predetermined chemical composition and specific conditions of pressure and temperature.
Mohs Scale:
- Talc
- Gypsum
- Calcite
- Fluorite
- Apatite
- Orthoclase
- Quartz
- Topaz
- Corundum
- Diamond
Liquids: They are easier to manipulate than gases. It’s easy to transfer them from one container to another. They don’t have their own form; they take the form of the container that contains them. Their
Read MoreEmbryonic Body Cavity Development
Body Cavities, Mesentery, and Diaphragm
The Embryonic Body Cavity
The intraembryonic coelom becomes the embryonic body cavity, which gives rise to three coelomic body cavities during Week 4:
- Pericardial cavity
- Two pericardioperitoneal canals
- Peritoneal cavity
These cavities are lined with mesothelium: a parietal wall and a visceral wall covered with mesothelium. The peritoneal cavity is connected to the extraembryonic coelom at the navel. The pericardial cavity opens to the pericardial-peritoneal canals.
Read MoreEukaryotic Cell Structures: Walls, Glycocalyx, Cytoskeleton
Eukaryotic Cell Structures
Plant Cell Wall
Functions:
- Provides rigidity and contributes to the maintenance of cell shape.
- Links adjacent cells.
- Enables the exchange of fluids and intercellular communication.
- Allows the plant cell to live in a hypotonic medium, preventing bursting.
- Waterproofs plant surface tissue.
- Serves as a protective barrier against pathogens.
Structure and Composition:
Composed of cellulose and polysaccharides (pectin and hemicellulose). Layers are:
- Lamella Media (outermost layer): Consists
Population Ecology: Dispersion, Demography, and Growth
Population Ecology: Key Concepts
- Dispersal is the movement of individuals or gametes away from centers of high population density or from their area of origin.
- Endemic species are those that are only found in a small, specific area.
- Species transplants include organisms that are intentionally or accidentally relocated from their original distribution.
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If a transplant is successful, it indicates that the potential range of a species is larger than its actual range.
- Guppy populations evolve rapidly