Exercise 2 Flashcards
What is chromatin? What is the difference between chromatin and chromosomes? Where are they located?
The chromatin is fine, thin thread like structures found in the nucleus. Chromatin is visible as a dark mass within the nucleus. Chromosomes are formed when chromatin coils into short, thick, rod like structures just before cell division.
What is produced in the nucleolus?
It produces rRNA (ribosomal RNA).
The nucleolus is found within the nucleus of the cell. It is indicated as a dark region amidst the ribosomes.
What happens to the rRNA in the nucleolus?
rRNA joins with proteins to form the building blocks or subunits of ribosomes.
Where is the nuclear envelop found, and what is it’s function?
The nuclear envelope is a double membrane that surrounds the outside of the nucleus separating it from cytoplasm.
What are ribosomes composed of? Where are they located? What is their function?
Ribosomes are organelles found free within the cytoplasm or are attached to the endoscopic reticulum. They are composed of protein and rRNA. Their function is to act as the site where proteins are built.
What is the function of the nucleus?
The nucleus store genetic information in the form of DNA.
What organelles make up the endomembrane system and what is its purpose?
Nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes and vesicles. The system divides the cells into specific compartments so that particular enzymatic reactions happen only in certain areas of the cell.
Briefly describe the endoplasmic reticulum. What is the difference between rough and smooth endoplasmic reticulum.?
The endoplasmic reticulum is a complex system of channels formed of membranes and flattened vesicles called saccules.
ROUGH ER contains ribosomes on the side of the membrane that faces the cytoplasm and is responsible for synthesising protein.
SMOOTH ER is a continuous with Rough ER but does not contain ribosomes and is not involved in protein synthesis. It is involved in other functions including building phospholipids.
What is the function of lysosomes?
Lysosomes are specialised vesicles made by the Golgi apparatus. They contain digestive enzymes. Digestion of substances.
What is the role of mitochondria in the cell, and what do we call the mitochondria because of this role?
They are involved in cellular respiration and produce ATP.
Often referred to as the power house of the cell.
What is ATP?
Adenosine trisphosphate. Carrier of energy for the cell.
What happens during cellular respiration? Why is this process so important in the cell?
During cellular respiration the chemical energy of carbohydrates, usually glucose, combines with oxygen that we breathe in. This form of metabolism produces carbon dioxide and water molecules, but more importantly energy packaged as ATP is released. The cell will have a use for the water and certainly the energy, but carbon dioxide is not required and will be exhaled out of the body.
