Amoeba Sisters worksheet on the properties of water, featuring educational diagrams and questions about polarity, solvent ability, adhesion, cohesion, and hydrogen bonds.
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Step-by-step solution for: Amoeba sisters DNA vs RNA video recap worksheet by Grade 9 Biology
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Show Answer Key & Explanations
Step-by-step solution for: Amoeba sisters DNA vs RNA video recap worksheet by Grade 9 Biology
Let's go through each question on the Amoeba Sisters Video Recap: Properties of Water worksheet and provide clear, accurate answers with explanations.
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Answer:
In a water molecule (H₂O), oxygen is more electronegative than hydrogen. This means oxygen has a stronger pull on the shared electrons in the covalent bonds between oxygen and hydrogen. As a result, the electrons spend more time near the oxygen atom, giving it a partial negative charge (δ⁻). The hydrogen atoms, having less electron density, become partially positive (δ⁺). This uneven distribution of charge makes the water molecule polar, with a bent shape that enhances the polarity. The graphic shows the oxygen pulling electrons away from the hydrogens, creating the dipole (positive and negative ends).
> 🔹 Key idea: Electronegativity difference → unequal sharing → polar molecule.
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Answer:
Water’s ability to dissolve many substances makes it essential for life. For example, in the human body, water acts as a solvent in blood plasma, dissolving ions like sodium (Na⁺) and chloride (Cl⁻), glucose, amino acids, and gases like oxygen and carbon dioxide. This allows these vital substances to be transported throughout the body to cells. Without water as a solvent, nutrient transport, waste removal, and chemical reactions would not occur efficiently.
> 🔹 Example: Blood uses water to carry nutrients and oxygen to cells and remove metabolic wastes.
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Answer:
- Cohesion: The attraction between water molecules due to hydrogen bonding. This causes water molecules to stick together.
- Adhesion: The attraction between water molecules and other substances (like the walls of xylem vessels in plants).
These properties are crucial for water transport in plants. Cohesion allows water molecules to form a continuous column in the xylem, while adhesion helps water stick to the sides of the xylem vessel. Together, they enable capillary action and help pull water upward from the roots to the leaves against gravity, even in tall trees.
> 🔹 Why important? Adhesion and cohesion work together to move water up the plant via transpiration pull.
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Answer:
The image shows cohesion, which is the tendency of water molecules to stick to each other. The insect (likely a water strider) is able to walk on water because of the surface tension created by cohesive forces.
Hydrogen bonds between water molecules create strong intermolecular attractions. These bonds allow water molecules at the surface to be pulled inward, forming a "skin" or surface tension. This surface tension supports small objects like insects, preventing them from breaking through the surface.
> 🔹 How hydrogen bonds contribute: Hydrogen bonds make water molecules strongly attracted to each other, increasing surface tension and enabling cohesion.
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| Property | Explanation |
|--------|------------|
| Polarity | Unequal sharing of electrons due to oxygen’s high electronegativity. |
| Solvent | Dissolves polar substances; essential for biological processes. |
| Adhesion & Cohesion | Help move water in plants via capillary action. |
| Surface Tension | Result of hydrogen bonding; allows insects to walk on water. |
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This worksheet highlights how water’s unique molecular structure leads to its critical roles in biology — from transporting nutrients to supporting life at the cellular level.
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1. The molecule of water is described as a polar molecule. Polar molecules have an unequal sharing of electrons. Explain how this unequal sharing is present by using our water molecule graphic below.
Answer:
In a water molecule (H₂O), oxygen is more electronegative than hydrogen. This means oxygen has a stronger pull on the shared electrons in the covalent bonds between oxygen and hydrogen. As a result, the electrons spend more time near the oxygen atom, giving it a partial negative charge (δ⁻). The hydrogen atoms, having less electron density, become partially positive (δ⁺). This uneven distribution of charge makes the water molecule polar, with a bent shape that enhances the polarity. The graphic shows the oxygen pulling electrons away from the hydrogens, creating the dipole (positive and negative ends).
> 🔹 Key idea: Electronegativity difference → unequal sharing → polar molecule.
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2. Water is an excellent solvent. With water being a polar molecule, it can be an especially strong solvent for other polar molecules. Give an example of how water acting as a solvent is important for living organisms.
Answer:
Water’s ability to dissolve many substances makes it essential for life. For example, in the human body, water acts as a solvent in blood plasma, dissolving ions like sodium (Na⁺) and chloride (Cl⁻), glucose, amino acids, and gases like oxygen and carbon dioxide. This allows these vital substances to be transported throughout the body to cells. Without water as a solvent, nutrient transport, waste removal, and chemical reactions would not occur efficiently.
> 🔹 Example: Blood uses water to carry nutrients and oxygen to cells and remove metabolic wastes.
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3. The below picture shows water’s ability for adhesion and cohesion. Define adhesion and cohesion and explain why they are important for the plant in the graphic below.
Answer:
- Cohesion: The attraction between water molecules due to hydrogen bonding. This causes water molecules to stick together.
- Adhesion: The attraction between water molecules and other substances (like the walls of xylem vessels in plants).
These properties are crucial for water transport in plants. Cohesion allows water molecules to form a continuous column in the xylem, while adhesion helps water stick to the sides of the xylem vessel. Together, they enable capillary action and help pull water upward from the roots to the leaves against gravity, even in tall trees.
> 🔹 Why important? Adhesion and cohesion work together to move water up the plant via transpiration pull.
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4. Describe the property of water being shown below. How do water’s hydrogen bonds contribute to this property?
Answer:
The image shows cohesion, which is the tendency of water molecules to stick to each other. The insect (likely a water strider) is able to walk on water because of the surface tension created by cohesive forces.
Hydrogen bonds between water molecules create strong intermolecular attractions. These bonds allow water molecules at the surface to be pulled inward, forming a "skin" or surface tension. This surface tension supports small objects like insects, preventing them from breaking through the surface.
> 🔹 How hydrogen bonds contribute: Hydrogen bonds make water molecules strongly attracted to each other, increasing surface tension and enabling cohesion.
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✔ Summary of Key Concepts:
| Property | Explanation |
|--------|------------|
| Polarity | Unequal sharing of electrons due to oxygen’s high electronegativity. |
| Solvent | Dissolves polar substances; essential for biological processes. |
| Adhesion & Cohesion | Help move water in plants via capillary action. |
| Surface Tension | Result of hydrogen bonding; allows insects to walk on water. |
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This worksheet highlights how water’s unique molecular structure leads to its critical roles in biology — from transporting nutrients to supporting life at the cellular level.
Parent Tip: Review the logic above to help your child master the concept of amoeba sisters worksheets.
