4-1: What are cells?
Define: A cell is the basic unit of structure and function in living things.
Name: Robert Hooke was the first person to see cells.
Restate:
- 1. Living things are made up of one or more cells.
- 2. Cells are the basic structure in living things and carry on all life processes.
- 3. Cells come only from other living cells.
Check:
- A theory is an idea that explains something and is supported by data.
- The cell is the basic unit of structure in living things.
- Robert Hooke was the first person to see cells.
- Anton van Leeuwenhoek saw living cells in a drop of pond water.
- Cells come from other living cells.
Apply:
6. Relate: As microscopes improved, there were more discoveries about cells
7. Apply: Cells do carry out respiration. They break down a simple sugar called glucose to get energy.
8. Apply: New cells could not be produced by the cork that Robert Hooke observed because those cells were no longer living. He only observed the cell walls of the cork cells.
4-2: What are the main cell parts?
Name: The three main cell parts are the cell membrane, the cytoplasm, and the nucleus
Infer: There would be no control center to control all of the life processes of the cell.
Describe: Most of the cells activities occur in the cytoplasm.
List: The cell membrane protects the inside of the cell, gives support and shape to the cell, and controls the movement of materials in and out of the cell.
Check:
- All the life processes of the cell are controlled by the nucleus.
- The cell membrane is also called the plasma membrane.
- The three main parts of the cell are the nucleus, the cell membrane, and the cytoplasm.
- The cell membrane controls the movement of material into and out of the cell.
- Most of the cell is made up of cytoplasm.
Apply:
- Apply: The nucleus controls respiration.
- Infer: The nuclear membrane has the same functions as the cell membrane; protection, gives shape, controls movement of materials in and out of the nucleus.
- Model: A = Cytoplasm; B = Nucleus, and C = Cell Membrane
4-3: What are other cell parts?
Define: Organelles are small structures that float in the cytoplasm that do special jobs.
Explain: A cell needs energy to carry out all of its life processes.
List: Vacuoles can store food, water, and waste.
Infer: The ribosomes can be called a “protein factory” because they are producing proteins.
Describe: The transports tubes (endoplasmic reticulum) are used to move materials around the cell.
Check:
- The “powerhouses” of the cell are ribosomes.
False – mitochondria
- Small structures in the cytoplasm are organelles.
True
- Ribosomes make proteins.
True
- Liquid-filled spaces are mitochondria.
False – vacuoles
- Ribosomes are smallrice-shaped structures.
False – round
Apply:
- Compare:
Railroad = Transport Tubes (Endoplasmic Reticulum)
Cabinet = Vacuoles
Battery = Mitochondria
Electric Company = Mitochondria
- There are probably more mitochondria in muscle cells than in skin because the muscle cells need more energy.
-
4-4: How do plant and animal cells differ?
Name: Most of the cell wall is made of cellulose.
Observe: The plant cell in the above diagram has two vacuoles.
Explain: Most plants are green because plant cells contain chloroplasts which contain a green substance called chlorophyll.
Check:
- Large plants do not need a skeleton because they have thick cell walls made of cellulose.
- The cell walls protect the plant cells, give them shape, and they give the plant support.
- Chloroplasts are the structures where plants make their own food by photosynthesis.
- Cellulose is a hard, nonliving material that makes up the cell wall of a plant cell.
- There are more vacuoles in animal cells and they are smaller in animal cells. Plant cells have one large vacuole (sometimes two).
- Plants need chlorophyll to make their food.
Apply:
- Compare: a. Plant and animal cells both have a cell membrane, a nucleus, cytoplasm, mitochondria, and vacuoles. b. Plant cells have a cell wall and chloroplasts and animal cells do not. Plant cells have one or two large vacuoles and animal cells have several small vacuoles.
- Analyze: The following organisms contain cellulose:
- a. pine tree
- d. fern
- e. grass
- Wood is mainly a nonliving material because it is made up of the hard material called cellulose. Cellulose is the material making up the cell walls of plant cells.