Cell: The Unit Of Life Flashcards
Who was Mathias Schleiden ?
A German botanist
What did Schleiden observe?
he observed, in 1838, that all plants are composed of different kinds of cells which form the tissues of the plant.
Who was Theodore Schwann?
A British Zoologist
What did Schwann report?
Upon studying different animal cells he reported, in 1839 that, cells had a thin outer layer (today known as plasma membrane).
Based on his studies on plant tissues he concluded that presence of cell wall is a unique character of the plant cells.
What hypothesis did Schwann propose?
The bodies of plants and animals are composed of cells and product of cells
Who formulated the cell theory?
Schleiden and Schwann together formulated the cell theory.
What did the Schleiden and Schwann hypothesis fail to explain?
it did not explain how new cells were formed.
Who modified the hypothesis given by Schleiden and Schwann?
Rudolf Virchow
What did Rudolf Virchow explain regarding cells?
Rudolf Virchow in 1855, first explained that cells divided and new cells are formed from pre-existing cells.
Omnis cellula-e cellula
What is the cell theory as understood today?
i) All living organisms are composed of cells and products of cells.
ii) All cells arise from pre-existing cells.
The two distinct compartments of intracellular space, made by ER:
Luminal (Inside ER)
Extra luminal (outside ER/ cytoplasm)
Full form of:
1) RER
2) SER
1) Rough Endoplasmic Reticulum
2) Smooth Endoplasmic Reticulum
True or False
RER is frequently observed in the cells actively involved in protein synthesis.
True
What is the major site for synthesis of lipid?
SER (Smooth Endoplasmic Reticulum)
Where are lipid-like steroidal hormones synthesised in animals cells?
SER
Who discovered Golgi bodies?
Camillo Golgi in 1898 discovered densely stained reticular structures near the nucleus , which were later named Golgi bodies.
What is the diameter of cisternae of golgi bodies?
0.5µm to 1µm
What are cisternae?
Many, flat disc shaped sacs of golgi complex.
True or False
Fixed number of cisternae are present in a golgi complex.
False
Varied number of cisternae are present in a golgi complex.
What are the two distinct faces of the golgi cisternae?
1) convex cis / forming face
2) concave trans / maturing face
True or False
The Golgi cisternae are eccentrically arranged near the nucleus.
False
They are arranged concentrically around the nucleus,
True or False
The cis and trans faces of golgi body are entirely different but interconnected
True
