The Cell Theory
Who coined the term cell?
Robert Hooke.
What is the maximum magnification of a compound light microscope?
1,000x.
What is the primary structural component of the cell membrane?
The phospholipid bilayer.
Which organelle is known as the “control center” of the cell?
The nucleus
What is osmosis?
The diffusion of water across a selectively permeable membrane.
Name one of the three main components of the cell theory.
All living organisms are made of one or more cells.
What are the two types of electron microscopes?
Scanning Electron Microscope and Transmission Electron Microscope.
What is the term for the cell membrane’s ability to control what enters and exits the cell?
Selectively permeable.
What is the function of the mitochondria?
To produce energy (ATP) through cellular respiration.
What is the energy source for active transport?
ATP.
What type of cells lack membrane-bound organelles?
Prokaryotic cells.
Can live specimens be observed under an electron microscope? WHY ?
No, because the preparation process kills the cells
Which type of transport does not require energy: diffusion or active transport?
Diffusion.
What structure gives plant cells their rigid shape?
The cell wall.
Which transport process moves substances against the concentration gradient?
Active transport.
What does the cell theory say about the origin of new cells?
All new cells come from pre-existing cells.
Which microscope provides 3D images of specimens?
Scanning Electron Microscope
What is facilitated diffusion?
The process where transport proteins help molecules move across the membrane.
What is the main difference between rough and smooth endoplasmic reticulum?
Rough ER has ribosomes attached, while smooth ER does not.
What happens during endocytosis?
The cell engulfs external substances by surrounding them with its membrane.
In what century was the cell theory developed?
The 19th century 1800s
What did Robert Hooke observe under a microscope when he coined the term cells?
Cork tissue resembling small rooms or cells.
What role does cholesterol play in the cell membrane?
It stabilizes membrane flexibility, especially in animal cells.
Which organelle is the site of photosynthesis?
Chloroplasts.
What is the name of the process where a cell expels substances outside through vesicles?
Exocytosis.