7th Grade Science 1st 9 Weeks Exam Study Guide
1. What is the difference in Quantitative observations and Qualitative observations? Quantitative observations involve a number ( three green seeds) and qualitative observations do not ( green seeds).
2. A _hypothesis______is an educated guess about the relationship between the independent and dependent variable.
3. What are factors in an experiment that can be changed? variables
4. What are the factors that an experimenter keeps the same during an experiment?Constants
5. The _Scientific Method (Process) ______is a series of steps used to investigate a natural occurrence.
6. Define an independent variable compared to a dependent variable. An independent or manipulated variable is the variable that you change on purpose during an experiment ( adding more sugar to the bread). The dependent or responding variable is what you are trying to change at the end of the experiment ( the size of the bread loaf).
7. Landon believes that rose bushes produce more roses when a solution of sugar and water is used to water the plants. Landon tests his hypothesis by watering one rose bush with plain water and another rose bush with a solution of sugar water.
A) What is the dependent variable? The amount of roses produced B) What is the control? The roses only watered with plain water C) What is the independent variable? The sugar
8. Define the differences in autotrophs and heterotrophs. Autotrophs are producers that make their own food. Heterotrophs are consumers ( like us) that eat other organisms.
9. Compare characteristics of prokaryotes with characteristics of eukaryotes (make a T-chart)
Prokaryotes – Eukaryotes -
Bacteria and ArchaeaAll other organisms on Earth except bacteria and Archaea
Do not have a true nucleus Have a true nucleus
10. What are the 3 parts of cell theory?1. All living things are made of cells. 2.) Cells are the basic unit of structure and function in living things. 3.) All cells come from preexisting cells.
11. Which scientist proposed that new cells come from pre-existing cells? Rudolph Virchow
12. Describe the functions of cell organelles:
A) nucleus – controls the activities of the cell
B) Cell membrane – only allows certain organisms into and out of the cell.
C) Chloroplast – Collects sunlight to allow some organisms to photosynthesize
D) Mitochondria – Power house of the cell where glucose is turned into energy
13. What are structures found in plant cells that are not found in animal cells?cell walls, chloroplasts, and one large vacuole (compared to many small vacuoles in animal cells).
14. Compare the purposes and products of photosynthesis with the products of cellular respiration.
Photosynthesis is the process in which organisms use the suns energy to make food ( aka. Glucose and sugar ). The products are Sugar and Oxygen. Respiration takes the glucose along with oxygen and turns it into energy , water , and CO2. They are exact opposites of each other .
15. _Mitosis______is the phase of cell division in which the cell’s nucleus divides into two nuclei.
16._Cytokinesis______is the phase of cell division that follows mitosis where cytoplasm divides into two daughter cells.
17.Cell Cycle______is the regular cycle of growth and division that cells undergo.
18. _Interphase______is the phase of the cell cycle in which replication occurs.
19. List the 5 steps of the scientific method.
1. State the problem
2. Research
3. Hypothesis
4. Experiment
5. Collect Data
6. Conclusion
7. Communicate
20. How is cytokinesis different in plant cells than in animal cells. In Plant cells a cell plate is formed due to the cell wall being more rigid than a cell membrane.
21. Draw a diagram of the cell cycle phases in order: Interphase, Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis.
A – Interphase, B – Prophase, C – Metaphase, D – Anaphase, E – Telophase, F - cytokinesis
22. A __centromere______is the structure that holds sister chromatids together. Label this structure in your drawings from #21.
23. How can you distinguish between a diagram of a plant cell and a diagram of an animal cell?
A plant cell will be more square due to the cell wall and will contain chloroplasts and one large central Vacuole. An animal cell will be more rounded and not contain a cell wall, chloroplasts, and will have several smaller vacuoles.
24. Draw a plant cell and label all of the organelles: Cell membrane, Cell wall, cytoplasm, Nucleus, Vacuole, Chloroplast, Mitochondria, Lysosomes, Endoplasmic Reticulum, Golgi Body, Ribosomes.