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Which of the following federal regulatory agencies enforces federal campaign laws?

A tax collected when an individual went to vote was called which of the following?

Which of the following groups of Americans turns out to vote at the lowest rate?

If no presidential candidate receives a majority of the electoral college votes, the election is decided by which of the following?

Which two states do not use a winner-take-all system in the electoral college?

Virtual Lab – Microscopy – Plant Cells (Onion Epidermal Cells)All living systems are made up of either prokaryotic or eukaryotic cells. Bacteria are prokaryotic organisms. Prokaryotic cells are generally smaller, less complex, and most importantly, the genetic material (DNA) is not enclosed in a membrane-bound structure (known as the nucleus). All bacteria are prokaryotes. Eukaryotic cells make up all the other kingdoms of life: plants, animals, fungi, and protists. Eukaryotic cells are generally larger, more complex in cellular organization, and have distinct membrane-bound structures known as organelles (including having a nucleus). Most cellular structures are too small and colorless to be visually identifiable using a light microscope. However, it is possible to visualize nuclei in eukaryotic cells using a light microscope. In this next simulation, you will observe onion epidermal cells, which are harvested from the inner portion of a layer from an onion bulb. The bulb of the onion grows underground so, therefore, the organelle which accomplishes photosynthesis, the chloroplast, will not be visible in an onion bulb. Furthermore, since most cellular structures are colorless, it is important to treat many kinds of cells with some kind of stain before observing them with a light microscope. The color contrast the stain provides allows better observation of cellular detail and activity.

Virtual Lab – Microscopy – Wet Mount (Euglena) What similarities and differences do you see between the cheek cells and the Euglena? Similarities: Cell Membrane: Both cheek cells and Euglena have a cell membrane that controls the movement of substances in and out of the cell. Differences: Structure and Function: Cheek cells are eukaryotic animal cells with a more irregular shape and lack specialized structures for movement or photosynthesis. Euglena, a protist, has a more elongated shape with a flagellum for movement and chloroplasts for photosynthesis. Organelles: Cheek cells contain organelles such as a nucleus, mitochondria, and lysosomes but lack chloroplasts. Euglena contains a nucleus, mitochondria, and chloroplasts.

Virtual Lab – Microscopy – Animal Cells (Human Epidermal Cells) Animal cells are another example of a eukaryotic cell. They are surrounded by a selectively permeable membrane called a plasma membrane and they have a large nucleus that contains genetic material. Some animal cells are motile with cilia or flagella. The animal cells that we will be observing in this simulation come from the inside of our mouths (cheek epidermal cells). Cheek cells are squamous epithelial cells that line the inside of our oral cavity. They protect the cells underneath and secrete mucin to lubricate the oral cavity. Cheek cells divide quickly and they shed easily. Every time you eat, you are swallowing thousands of your own cheek cells. In this activity, we will observe cheek cells from the inside of our mouths under the light microscope. Since most cellular structures are colorless, it is important to treat many kinds of cells with some kind of stain before observing them with a light microscope. The color contrast the stain provides allows better observation of cellular detail and activity.

Virtual Lab – Microscopy – Plant Cells (Onion Epidermal Cells) Many organelles are not visible in onion cell images primarily due to the following reasons: Size and Resolution Cell Wall and Structure Staining Techniques

Virtual Lab – Microscopy – Plant Cells (Onion Epidermal Cells) The general shape of an onion cell is typically circular or spherical.