Cell Structure and Diversity Flashcards
What is tissue?
A group of cells that work together to perform a specific function
What is the function dermal tissue in plants?
Protects the plant
What is the function of vascular tissue in plants?
Transports water, food and minerals around the plant
What adaptation does xylem have for strength?
Enforced with lignin
What adaptation do leaves have to prevent water loss?
Waxy cuticle
What is nervous tissue in animals responsible for?
Carries electrical impulses to and from the central nervous system (CNS)
What is the function of connective tissue in animals?
Provides support and protection
What adaptation does nervous tissue have for rapid signal transmission?
Myelin sheath
What is tissue culture?
The growth of cells outside of the body, on a sterile nutrient medium
What adaptation allows muscle tissues to facilitate movement?
Can contract and relax
What are some uses of tissue culture?
- Skin grafts for skin cancer/burn patients
- Cancer research
What conditions are necessary for tissue culturing?
- Micropropagation of plants
- Oxygen
- Nutrients
- Correct pH
- Optimum temperature
- Sterile conditions
- No competition
What is an organ?
A group of tissues that work together to perform a function
Name three plant organs.
- Leaf
- Flower
- Stem
- Root
Name four animal organs.
- Lungs
- Stomach
- Heart
- Liver
- Kidneys
What is an organ system?
A group of organs that work together to perform functions
Name three animal organ systems.
- Respiratory system
- Urinary system
- Digestive system
What is the function of the coarse focus?
Used for initial focusing of the image on the slide
Coarse focus allows for quick adjustments to the focus of the microscope.
What does the fine focus do?
Provides precise focusing of the image on the slide
Fine focus is adjusted after coarse focus for clearer details.
What is the purpose of the stage in a light microscope?
The slide is placed on the stage
The stage supports the slide and allows for movement.
What does the eyepiece lens do?
Magnification of the image
The eyepiece lens is the part you look through.
What is the function of the objective lens?
Magnification of the image
Different objective lenses provide varying levels of magnification.
What does the clip do in a light microscope?
Holds the slide in place
The clip secures the slide to prevent movement.
What is the role of the condenser in a light microscope?
Focuses light onto the slide
The condenser improves image clarity by directing light.
What does the diaphragm do?
Adjusts the amount of light shining on the slide
The diaphragm controls light intensity for better visibility.
How do you adjust the stage height?
Using the stage height adjuster
This allows for vertical movement of the stage for focusing.
What is the first step in using an electron microscope?
Use the lowest power objective lens first
Starting with lower power helps in locating the object.
What is the purpose of firing electrons at the object in an electron microscope?
Allows us to see the object by bouncing off electrons
This technique provides higher resolution images.
How is magnification calculated?
By multiplying the power of the eyepiece lens by the power of the objective lens
This calculation helps in determining the overall magnification of the image.
Fill in the blank: The _______ is used to hold the slide in place on the stage.
clip
The clip secures the slide during observation.
True or False: The coarse focus knob is used for fine adjustments to the image.
False
The coarse focus is meant for rough adjustments, while the fine focus is for detail.
What is the function of the nosepiece?
Holds the objective lenses
The nosepiece allows for easy switching between different objective lenses.
What is the smallest functional unit of life?
The cell
The cell is essential for all biological processes.
What is ultrastructure?
The structure of a cell that can be seen under an electron microscope
Ultrastructure provides detailed insights into cellular components.
What is the function of the nucleus in animal cells?
Contains DNA and RNA and controls the cell processes
The nucleus is often referred to as the control center of the cell.
What is the composition of the cell membrane?
Composed of phospholipids and proteins
The cell membrane regulates the entry and exit of substances.
What is the primary function of ribosomes?
This is where proteins are made
Ribosomes can be found free in the cytoplasm or attached to the endoplasmic reticulum.
What is the role of mitochondria in the cell?
Provides energy during respiration
Mitochondria have cristae that increase surface area for energy production.
What does the cytoplasm contain?
A viscous, jelly-like liquid that contains and stabilizes the organelles
The cytoplasm is the site for most metabolic processes.
What are nuclear pores?
Areas in the nuclear membrane made of various proteins through which molecules can pass in and out of the nucleus
Nuclear pores are crucial for the transport of materials between the nucleus and cytoplasm.
Fill in the blank: DNA stores our _______.
genetic material
DNA is essential for heredity and cellular function.
What is the overall magnification if the power of the eyepiece lens is 10x and the power of the objective lens is 4x?
40
Magnification is calculated by multiplying the eyepiece magnification by the objective lens magnification.
What is the function of the nucleolus?
Contains chromatin
The nucleolus is involved in the production of ribosomes.
What is the purpose of applying methylene blue as a stain?
To clearly see the cells
Stains enhance visibility of cellular structures under a microscope.
What angle should a cover slip be added to avoid air bubbles?
45 degrees
This technique helps in preventing air bubbles that can obstruct viewing.
What is the function of the cell wall?
Gives the cell its shape, strengthens the cell, and prevents it from bursting
The cell wall is a crucial structural component in plant cells.
What is the vacuole?
Vesicles surrounded by a membrane that have various functions, such as storage and waste removal
Vacuoles are important for maintaining cell turgor and storage.
Where does photosynthesis take place?
In the chloroplast
Chloroplasts contain chlorophyll, which traps light energy for photosynthesis.
What is protoplasm?
The collective term for the cytoplasm and nucleoplasm
Protoplasm encompasses all the living contents of a cell.
Define prokaryotes.
Organisms whose cells do not have a membrane bound nucleus or membrane bound organelles
Examples include bacteria.
Define eukaryotes.
Organisms whose cells have a membrane bound nucleus and membrane bound organelles
Examples include plants and animals.
What is the purpose of applying iodine as a stain?
To enhance visibility of plant cells
Iodine is commonly used to stain starch and cellular structures.
What is contained within chloroplasts that aids in photosynthesis?
Chlorophyll
Chlorophyll is the pigment that captures light energy.
What does the nucleus contain?
The cell’s genetic material
The nucleus is the control center of the cell.
What is the role of the cover slip in microscopy?
To protect the lens and prevent the cells from drying out
Proper use of a cover slip is essential for clear imaging.
Fill in the blank: The _______ is where photosynthesis takes place.
chloroplast
Fill in the blank: Protoplasm includes the _______ and nucleoplasm.
cytoplasm
True or False: Eukaryotic cells lack a membrane-bound nucleus.
False
Eukaryotic cells are defined by their membrane-bound nucleus.
