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Life Science Ch.3 7th Grade Midterm Study Guide

Terms in this set (43)

What is the thin covering that all cells have?
The cell membrane
What is cytology?
The study of cells
What is the meaning of the fluid mosaic model?
The fluid mosaic model resembles an artistic mosaic and it shows proteins scattered throughout a lipid bilayer.
How does a selectively permeable membrane affect the cell?
It allows some substances to pass through and into the cell, but not others.
What type of transport requires the cell to use its own energy?
Active Transport
If you wake up one morning to the aroma of bacon which is in a pan in the kitchen, what has taken place?
Diffusion
True or False - During diffusion, a substance moves from an area of high concentration to an area of lower concentration.
True
Osmosis is the diffusion of _________ through a(n) _________ membrane.
water; selectively permeable
Who was Anton van Leeuwenhoek?
He discovered bacteria and protozoans with microscopes he made himself.
What is significant about the cell membrane?
It is a part of all cells.
How do you find the total magnification of a compound light microscope?
Multiply the magnification powers of the eyepiece times the objective that you're using.
The "powerhouses" of the cell that release usable energy for the cell are the _______.
mitochondrion
What is the function of the ribosomes?
They direct the assembling of the proteins.
"Garbage disposal" would best describe the function of which organelle?
The lysosomes
What is turgor pressure?
The term used for the stiffness of a cell that has plenty of water
Which organelle contains the cell's genetic information?
The nucleus
If the genetic material of Serratia marcescens is not surrounded by a membrane, then it is _______. Because of this, the cell is probably a _________.
prokaryotic; bacterium
True or False - Most eukaryotic cells contain about the same number of each type of organelle.
False, because they are very diverse.
True or False - Chloroplasts are found in both plants and bacteria.
False
True or False - Chloroplasts are found in plant cells but not animal cells.
True
Many parts of the cell work together. If any part is removed then the cell may not be able to work. This is an example of...
irreducible complexity
List the organelles found in an animal cell
1. nucleus
2. cell membrane
3. mitochondrion
4. lysosomes
5. ribosomes
6. Golgi apparatus
7. vacuole
8. possibly cilia
9. endoplasmic reticulum
10. cytoplasm
11. possibly flagella
List the organelles found in a plant cell
1. cell membrane
2. cell wall
3. chloroplast
4. mitochondrion
5. nucleus
6. vacuole
7. Golgi apparatus
8. ribosome
9. endoplasmic reticulum
Be able to label a diagram of an animal cell
Be able to label a diagram of a plant cell
What are some differences between animal and plant cells?
>Plant cells have chloroplasts
>Plant cells have a central vacuole
>Plant cells have a cell walls
>Animal cells have lysosomes
>Animal cells may have cilia and flagella, but plants don't
>They have different shapes
Be able to label a diagram of a microscope
What is passive transport?
It moves substances through the membrane without use of the cells own energy.
What is osmosis?
The diffusion of water through a selectively permeable membrane
What is the cytoplasm?
The thick fluid that contains many small organelles
What is an organelle?
The parts of a cell that perform many of the functions needed to keep the cell alive
What is the mitochondria?
The "powerhouse" of the cell; enzymes transform small food molecules into usable energy.
What is the endoplasmic reticulum?
The cell's delivery system; connects the nucleus to the cell membrane.
What are the ribosomes?
They direct the assembling of proteins.
What is the Golgi apparatus?
It collects, processes, and moves chemicals.
What are the vacuoles?
Serve as storage containers in the cytoplasm; may contain food, water, wastes, fats, or products being stored by the cell.
What are the lysosomes?
"Demolition crew"; Dissolve away cellular structures that are no longer needed; depose of foreign substances.
What are the chloroplasts?
Contain chlorophyll to capture energy from sunlight (photosynthesis).
What are the cilia and flagella?
Hairlike structures on the outside of some cells that function as movement.
>Cilia: many short hair
>Flagella: a few longer hairs
What is the nucleus?
The control center of the cell; surrounded by a nuclear membrane; contains DNA.
What are some characteristics of eukaryotic cells?
>Have a true nucleus
>Have membrane-bound organelles
What are some characteristic of prokaryotic cells?
>Have no true nucleus
>Don't have membrane-bound organelles
Reminder: What is irreducible complexity?
If one part of the cell doesn't work right, then the cell will most likely die.
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