Cell Unit Flashcards
(41 cards)
What is the function of a cell’s nucleus?
A nucleus contains the cell’s DNA and is the control centre. It controls all activities from within the cell
What is the function of a cell’s cytoplasm?
It holds all organelles in place
What is a cell wall?
It is found in plant cells and it protects the cell and keeps its shape. It acts like a sturdy barrier
What is a cell membrane?
A thin coating surrounding a cell that controls what enters and leaves the cell. It is a protective barrier.
What is a stereoscope?
A microscope that includes two eye pieces that allow a scientist to observe with both eyes
Who was Anton van Leeuwenhoek?
A scientist who discovered bacteria, free-living and parsitic microscopic protists, sperm cells, blood cells, microscopic nematodes and rotifers.
What did matthias schleiden discover?
He was the first to state that plants are made of cells and to stress how important a cell’s nucleus is
What is the definition of a prokaryotic cell?
These are unicellular organisms without a nucleus or organelles that are very small in size. They only have ribosomes
What did Robert Hooke do?
Looked at cork under a microscope and was the first person to observe cells.
Who was theodor Schwann?
A scientist who concluded that all animals are composed of cells
What did Rudolph Virchow do?
Stated that his theory that all cells come from existing cells
Explain unicellular
An organism made up of one cell
Explain multicellular
An organism made of more than one cell
SEM
Scanning electron microscope… Organisms need to be encased in gold to be studied in through this microscope
TEM?
This stands for transmission electron microscope. Specimen need to be sliced into thin slices after being frozen or encased in plastic
What are the three cell theory tenets?
- All living things are composed of cells.
- The cell is the basic unit of structure and function in living organisms.
- New cells are produced from existing cells
What are ribosomes?
Small structures where protein is manufactured
Define flagella
This “tail-like” feature provides whip-like movement; allows bacteria to swim
What is the nucleoid region in a bacterial cell?
A circular strand of genetic material that can be exchanged with other bacteria
What is pili?
Small hair-like structures that attach to surfaces; sometimes used in reproduction
What is the function of mitochondrion?
To create energy for the cell
What is chloroplast used for?
Plant cells use it to absorb sunlight and use it to make sugars and starches to feed themselves
What is the cytoskeleton?
It is both a muscle and a skeleton and is responsible for cell movement, cytokinesis, and the organization of organelles in a cell
What is an ocular lens
The lens or system of lenses of a microscope or telescope.
