Class 9 Science Chapter 5 MCQ

Here, are all the statements are correct. Hence, your answer will be option [D].

Grana are stacks of membrane bounded flattened discoid sacs containing the molecules of chlorophyll.

In 1938 Schleiden proposed the idea that plants consist of cells. Later in the year 1839, Schwann independently asserted that all animals and plants are made up of cells. This joint finding forms the basis of cell theory. The cell theory was refined further in 1855, when R. Virchow presented the idea that all cells arise from pre-existing cell. His amorphism was (Omnis Cellula-e-Cellula).

Here, are all the statements are correct. Hence, your answer will be option [D].

The cell walls of adjacent cells are glued together by the plasmodesmata.

Other than nucleus mitochondria contains DNA and are able to synthesise their own proteins they are regarded as semi-autonomous organelles.

The endoplasmic reticulum performs the following functions: (i)It increases the surface area of the cytoplasm for various metabolic activities of the cell. (ii)It gives internal support to the colloidal matrix i.e., cytoplasm. (ii)It is associated with the synthesis, storage and transport of metabolic products. (iv)It helps in the formation of the cell plate and nuclear membrane during cell division. (v)Routh Endoplasmic Reticulum (RER) is associated with the synthesis of proteins. (iv)Smooth Endoplasmic Reticulum (SER) secretes lipids which along with proteins constitute cell membrane by a process called membrane biogenesis.

The undefined nuclear region is the cytoplasm of prokaryotic cells is called nucleoid. The prokaryotic cells consist of a single chromosome, which is direct content of the cytoplasm i.e., there is no nuclear membrane in a eukaryotic cell, the nuclear envelope separates the nucleus from the cytoplasm. The nuclear envelope contains many pores (the nuclear pores) and encloses the liquid ground substance, the nucleoplasm. Within nucleoplasm two types of nuclear structures are embedded-the nucleolus and chromatin material. The nucleolus may be one or more in number and is not bounded by any membrane. It is rich in protein and RNA (Ribonucleic Acid) molecules and acts as the site for ribosome formation, hence are also known as factory of ribosomes.

Along with the function of secretion of various enzyme proteins and producing vacoules, Golgi apparatus is also involved in the synthesis of cell wall, plasma membrane and lysosome. Nucleus, mitochondria and plastids have their own genome (i.e., DNA) and ribosomes. They are self-replicating organelles i.e., they have power to divide and are able to synthesise their own structural protein (semi-autonomous organelles). Mitochondria is site of cellulose respiration and synthesis of energy rich compounds (ATP). Therefore, it is called as power house of the cell. The part of cell which between the plasma membrane and nuclear envelope is called the cytoplasm

Endoplasmic reticulum exists as a membranous network, which is connected to the outer membrane of nucleus from one side and plasma membrane to the other. It occurs in three forms (i)Cisternae-closed fluid filled sac (ii)Vesicles (iii)Tubules It is of two types, smooth endoplasmic reticulum i.e., without ribosomes on its surface and rough endoplasmic reticulum with ribosomes on its surface.