1. What affects the movement of water across the plasma membrane? 2. What will happen when human red blood cells are placed in a hypertonic salt/sugar solution? 3. Why bacteria are prokaryotic cells? 4. Why is endocytosis found in animals only? 5. In what form of DNA is present in a non-dividing cell? How this material changes when the cell is about to divide? 6. Do you agree that “A cell is a building unit of an organism”? If yes, explain why? 7. Write the name of different plant parts in which chromoplast, chloroplast, and leucoplast are present. 8. a. List various components of the nucleus. b. What are chromosomes? Give their chemical composition. 9. a. Name the phenomenon which helps freshwater unicellular organisms (eg. Amoeba) continuously gain water in their bodies. Also, name the mechanism by which these organisms throw out excess of water from their bodies. b. Give at least two examples in plants where a similar phenomenon is used to gain water. 10. If the organization of a cell is destroyed due to some physical or chemical influence. What will happen? 11. Why does the skin of your finger shrink when you wash clothes for a long time? 12. A person takes a concentrated solution of salt, after some time, he starts vomiting. What is the phenomenon responsible for such a situation? Explain. 13. If you are provided with some vegetables to cook. You generally add salt into the vegetables during the cooking process. After adding salt, vegetables release water. What mechanism is responsible for this? 14. If cells of onion peel and RBC are separately kept in a hypotonic solution, what among the following will take place? Explain the reason for your answer. 15. Bacteria do not have chloroplast but some bacteria are photoautotrophic and perform photosynthesis. Which part of the bacterial cell performs this? 16. Name the organelles which show the analogy written as under a. Transporting channels of the cell. b. A powerhouse of the cell. c. Packaging and dispatching unit of the cell. d. Digestive bag of the cell. e. Storage sacs of the cell. f. The kitchen of the cell. g. The control room of the cell. 17. How are chromatin, chromatids, and chromosomes related to each other? 18. What are the consequences of the following conditions? a. A cell containing higher water concentration than the surrounding medium. b. A cell having low water concentration than the surrounding medium. c. A cell having equal water concentration to its surrounding medium. 19. Give scientific reasons for the following: a. The inner membrane of mitochondria is deeply folded. b. Mitochondria can make some of their proteins. 20. 0.9% of NaCl solution is considered isotonic for RBCs. If RBCs are placed in a 2% NaCl solution, what will happen to the cells? What is such a solution called? 21. Nisha was observing live cells of onion in the biology laboratory and she observed cell wall cytoplasm and nucleus. Suddenly her friend spilled a few drops saltwater on the slide. After some time Nisha observed the slide and fond some changes. a. What would have been the change in live cells of onion peel after adding saltwater? b. Name the type of process. 22. If the tissue has at a given time 1024 cells, how many cycles of mitosis had the original parental single-cell undergone? 23. An ovary has 2400 ova. How many ova mother cells must have been there to produce them?
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When a cell is placed in a hypotonic environment, water will enter the cell, and the cell will swell. ... If placed in a hypotonic solution, a red blood cell will bloat up and may explode, while in a hypertonic solution, it will shrivel—making the cytoplasm dense and its contents concentrated—and may die.
If a plant cell is placed in a hypertonic solution, the plant cell loses water and hence turgor pressure by plasmolysis: pressure decreases to the point where the protoplasm of the cell peels away from the cell wall, leaving gaps between the cell wall and the membrane and making the plant cell shrink and crumple.
The endomembrane system includes the nuclear envelope, the endoplasmic reticulum, Golgi apparatus, lysosomes, vesicles, as well as the plasma membrane. These cellular components work together to modify, package, tag, and transport membrane lipids and proteins.
A hypertonic solution has increased solute, and a net movement of water outside causing the cell to shrink. A hypotonic solution has decreased solute concentration, and a net movement of water inside the cell, causing swelling or breakage.
The plasma membrane is selectively permeable; hydrophobic molecules and small polar molecules can diffuse through the lipid layer, but ions and large polar molecules cannot. Integral membrane proteins enable ions and large polar molecules to pass through the membrane by passive or active transport.
A 0.9% NaCl solution is said to be isotonic: when blood cells reside in such a medium, the intracellular and extracellular fluids are in osmotic equilibrium across the cell membrane, and there is no net influx or efflux of water.
If a plant cell is placed in a hypertonic solution, the plant cell loses water and hence turgor pressure by plasmolysis: pressure decreases to the point where the protoplasm of the cell peels away from the cell wall, leaving gaps between the cell wall and the membrane and making the plant cell shrink and crumple.
If you place an animal or a plant cell in a hypertonic solution, the cell shrinks, because it loses water ( water moves from a higher concentration inside the cell to a lower concentration outside ). So if you get thirsty at the beach drinking seawater makes you even more dehydrated.
The Golgi apparatus, also called Golgi complex or Golgi body, is a membrane-bound organelle found in eukaryotic cells (cells with clearly defined nuclei) that is made up of a series of flattened stacked pouches called cisternae. It is located in the cytoplasm next to the endoplasmic reticulum and near the cell nucleus.
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because they move by the movement of seeds