Tag: structural organization in living organisms

Plant and animal cells have several differences and similarities. For example, animal cells do not have a cell wall or chloroplasts but plant cells do. Animal cells are round and irregular in shape while plant cells have fixed, rectangular shapes.

The main difference between an animal cell and a plant cell is that plant cells have a cell wall, which the animal cells lack. The cell wall which is made up of cellulose gives the plant cell rigidity resulting in a fixed, rectangular shape. Animal cells lack the rigidity hence, they tend to have a round and irregular shape. Animal cells tend to vary greatly in appearance. The cell wall allows high pressure to build inside of the plant cell without bursting. Due to this, the plant cell is able to accept large amounts of liquid through osmosis without bursting. Animal cells, which only have a thin membrane restricting access to the cell, tend to burst if they absorb too much extra water.

Cellulose forms an integral part of the cell wall which provides strength and rigidity to the cell. It helps to maintain the structural integrity of a particular cell. Cellulose is a complex polysaccharide which is made up of β(1→4) linked D-glucose units.

The plant cell contains three different types of cell organelles which have two membranes. The chloroplast, mitochondria and the nucleus are the organelles which are surrounded by double membranous structures. The chloroplast is involved in photosynthesis, mitochondria performs respiration and the nucleus controls the activity of the other organelles. 

Cellulose forms an integral part of the cell wall which provides strength and rigidity to the cell. It helps to maintain the structural integrity of a particular cell. Cellulose is a complex polysaccharide which is made up of β(1→4) linked D-glucose units.

Vacuoles are found in almost all the cells. A plant cell usually has a large central sap vacuole. Most mature plant cells have one large vacuole that typically occupies more than 30% of the cell's volume, and that can occupy as much as 80% of the volume for certain cell types and conditions. Another important characteristic of a plant cell is the presence of a cellulosic cell wall. The plant cell wall is dead at maturity and is rigid. Hence, cell wall provides support and maintains the shape of a plant cell.

Plant cells have a strong cell wall surrounding them. When they take up water by osmosis they start to swell, but the cell wall prevents them from bursting. As a result, the plant cells become “turgid” when they swell up and become turgid.

• Plant cells store fat in sphaerosome.
  
• Spherosomes or oleosomes can be defined as small cellular organelles found in plant cells that are enclosed by a single membrane. 
  
• It is mainly responsible for the storage and synthesis of lipid. 
  
• They are obtained from the endoplasmic reticulum and are surrounded by a phospholipid monolayer.
  
• So, the correct answer is 'Sphaerosome'.
  

• A plant cell having more than two nuclei is known as coenocyte.
  
• Coenocyte refers to a multinucleate condition of the cell (algae, fungi or plant) which occurs due to the multiple nuclear divisions which are not followed by cytokinesis.
  
• So, the correct answer is 'Coenocyte'.