All living forms on earth i.e animals and plants are active, have phases like birth, growth, reproduction and death. Besides in all these phases they survive or stay alive and active by physiological and metabolic processes happening inside their body. Their body is made up of basic unit namely cell which has all the above phases and also features. The cell has many cell organelles inside which carry out the physiology and metabolism required to stay alive and also other phases.
For details on cell organelle s and their functions check out List of cell organelles and their function.
Plant cell phases: Based on their cell phases, cells forming tissues in plants are differentiated to parenchyma which is newly formed tissue and has potential to grow. While collenchyma tissue has no potential to grow but has physiology. While sclerenchyma had only dead cells but still support other function of plant by being converted to xylem , phloem etc. So the nature is that parenchyma converts to collenchyma and then as they age they convert to sclerenchyma with some hard dead substance namely legnin deposits.
Animal cell phases: Animal cell has no such phases. They just perform their normal physiology and once dead are replaced by new cells. Dead cells are removed of the body unlike in plants.
Animal cells and plant cell are similar to a great extent in terms of structure and physiology. Plants have small variation like presence of outer rigid cell wall, chloroplast for synthesis of own food by use of sunlight, presence of duct like cell structures to move water and other essential elements through their large and long bodies etc. Xylem is meant for water transport and phloem is meant for food transport.Their hormones that influence their physiology are different than animal’s cells.
Food: In animal cell, the food is supplied by some external source through by blood. So for food animal cell depends on some source but most plant cell synthesize their own food.
Excretion: waste of animal cell is removed of the cell and carried outside the body. IN plant cell, the waste is stored inside the cell or in the vicinity of the cell.
Respiration: In both plants and animals respiration is by mitochondria and energy is from combustion of carbohydrates in presence of oxygen. For more details on respiration read article on mitochondria and its characters .
Multiplication: Cells in both animals and plants multiply in their number by mitosis or meiosis. The difference is that mitosis gives rise to two new cells with same genetic trends as parent cell while meiosis gives four cell with half of the genetic trait of parent cell. Mitosis is for cell replacement while meiosis is for reproduction.
Cell death: In plant cells, the cells gets signified with age and lose the internal contents. This adds strength to plant though cell is dead. In animals the cell death results by apoptosis and necrosis.