B2 - Cells Flashcards
(29 cards)
What are the building blocks of life?
Cells
All organisms are composed of one or more cells.
What is the basic organisational unit of life?
The cell
All cells arise from pre-existing cells.
What type of organisms are made of many cells?
Multicellular organisms
Example includes humans.
What type of organisms are made of a single cell?
Unicellular organisms
Example includes bacteria.
What is the function of the cell membrane?
Separates cell content from surroundings and controls what goes in/out
It is a selective barrier containing receptor molecules.
What controls the activities of the cell?
The nucleus
It contains genetic information in chromosomes.
What is the cytoplasm?
A jelly-like substance with water, sugar, and salts where chemical reactions happen.
What is the role of ribosomes in the cell?
Protein is made
Ribosomes can only be seen with an electron microscope.
What process occurs in mitochondria?
Respiration
Mitochondria contain enzymes.
What do vacuoles do in plant cells?
Help keep the cell rigid and support the plant
They are full of cell sap.
What is the cell wall made of?
Cellulose
It makes the wall rigid and supports the cell.
What is the function of chloroplasts?
Photosynthesis
Found in green parts of the plant and contain chlorophyll.
What is the function of a light microscope?
Magnifies specimens.
What is the formula for total magnification in light microscopes?
Magnification of eyepiece lens x Magnification of objective lens.
What do cover slips do?
Flatten specimens, hold them in place, and stop them from drying.
What is the structure of bacterial cells?
Cell wall, cell membrane, cytoplasm, ribosomes, circular DNA, plasmids
Bacteria do not have a nucleus or membrane-bound organelles.
How do bacteria reproduce?
By binary fission
DNA is copied, and each daughter cell has one loop after division.
What is the function of red blood cells?
Transport oxygen.
What is unique about the shape of red blood cells?
Bi-concave disc shape
This increases the surface area for oxygen absorption.
What do ciliated cells do?
Move mucus in the trachea and bronchi.
What is the function of palisade cells?
Photosynthesis
They have many chloroplasts and a column shape to maximize sunlight absorption.
What is the role of root hair cells?
Absorption of water and minerals.
What is the function of sperm cells?
Reproduction.
What does the acrosome in sperm cells contain?
Digestive enzymes to penetrate the egg.
