A. The right answer is Rough endoplasmic reticulum
The granular endoplasmic reticulum is the place of synthesis (in the associated ribosomes) of the proteins secreted outside the cell and of the proteins and lipids constituting the membranes of the cellular organelles. Golgi, lysosomes, mitochondria, nucleus, ribosomes, vesicles ...). It participates in the correct folding of the proteins that have just been synthesized.
B. The right answer is Cytoplasm.
The cytoplasm corresponds to the medium found inside the cells. It is therefore delimited by the plasma membrane and contains within it, in eukaryotes, the nucleus, but also all intracellular organelles (ribosomes, endoplasmic reticulum, Golgi apparatus, mitochondria, various plastids, etc.).
C. The right answer is Smooth endoplasmic reticulum.
The endoplasmic reticulum is a eukaryotic cell organelle. He can be :
* granular (REG), that is to say associated with ribosomes that constitute the "granules";
* or smooth (REL).
The smooth endoplasmic reticulum participates in cellular metabolism, synthesizing lipids and storing calcium.
D. The right answer is Nucleolus
The nucleolus is the site of the transcription of ribosomal RNAs (rRNA) by the enzyme RNA polymerase I. These rRNAs (18S, 5.8S and 28S) will be used in ribosome production by associating with ribosomal proteins, a process that which is also facilitated by the factors contained in the nucleolus.
E. The right answer is Nucleus.
The nucleus contains the nuclear genome, consisting of DNA. DNA, bound to proteins, takes two forms, more or less condensed:
* euchromatin: less compacted, genes can be expressed;
* the heterochromatin: more compacted, on the periphery of the nucleus, the genes are extinguished or little expressed.
The nucleus is the main site of DNA synthesis (during replication for cell division) and RNA (for transcription).
The nucleus also contains a particular structure, the nucleolus, the locus of transcription of ribosomal RNAs.
F. The right answer is Mitochondria.
Mitochondria are small organelles (about 1 micrometer in length) essential in cellular energy processes.
The set of reactions that provides energy within the mitochondria constitutes cellular respiration.
Mitochondria are formed of an outer membrane, an inner membrane with many folds or ridges and a matrix which is the space between the folds of the inner membrane.
G. The right answer is Golgi apparatus.
The Golgi apparatus is an organelle of eukaryotic cells.
It is a major site for the transfer and sorting of molecules, as well as the synthesis of glycoproteins and sphingolipids.
By its position, between the endoplasmic reticulum and the plasma membrane, and its function, it is the intermediate between the maturation and the secretion of the proteins elaborated in the reticulum, it regulates the vesicular transport and is responsible for modifying the proteins by glycosylation, sulfation, etc.
H. The right answer is Lysosomes.
Lysosomes are 0.2 to 0.5 micron cell organelles present in the cytosol of all eukaryotic, animal cells, with the exception of erythrocytes ("red blood cells"). Their function is to carry out intracellular digestion (or extracellular digestion via exocytosis in the case of chondroblasts, osteoclasts and macrophages) thanks to about forty enzymes.
I. The right answer is Cell membrane.
The cell membrane delimits the cell. It separates the inside of the cell (the cytoplasm) from the outside environment. It is composed of phospholipids, between which proteins are inserted. Unlike the membranes of bacteria and plant cells, those of animal cells contain cholesterol molecules, which stiffens them and increases their impermeability to hydrophilic molecules.
