Chapter 2: Cell As A Unit of Life

Function of Structures in cell

We need to know the function of certain structure in both animal and plant cell for this topic.
This includes the below

Nucleus- Function to control all cell activity & contains gene the decides the inherited characters

Cytoplasm- Stores water and nutrients required for cell activity and chemical processes

Cell membrane- Protects the cell and serve as the barrier for movement of substances in and out of the cell

Cell Wall- functions to protect and mantain the shape of the cell

Chloroplast- contains pigment called chlorophyll which is required for photosynthesis.

Vacuole- holds cell sap in plants and waste substances in some lower animals.

In this Chapter, You need to know how to label the animal cell and plant cell.

Plant Cell

(They have chloroplast, vacoule, cell wall, fixed shape and they store their food in starch granules)

Animal Cell

(No Chloroplast, No Cell wall, No vacoule and some lower animals do have small vocuole, no fixed shape and storage of energy via glycogen granules)

To further understand the difference between Plant and Animal Cell- Please click on the below link

Difference between Plant and animal cell

Unicellular and multicellular Organisms

Organism- A living thing (plant or animal)

Microorganism- A living thing that cannot be seen by visible eyes- only under microscope
-eg: bacteria, viruses, algae, yeast, amoeba

Unicellular organism- Organism that has only one type of cell
- Usually found in water (ponds, lakes) or moist area- active and moving
- How they carry out life processes? – by moving, feeding and respiring

Multicellular organisms- Organisms that consist of many cells (plants and animals)

To watch video related to this please click on the below link

Unicellular and multicellular Organisms

Organisation of Cells in the Human Body

Cells-->Tissu-->Organs-->System

Cells - microscopic and can only be seen under the microscope
- examples- mucle cells, epithelial cells, red blood cells, white blood cells, nerve cells

Tissues- A group of cells performing the same function

Organs - Made up of a group of different tissues which carries out a specific function
- eg- leg (bone tissues, muscle tissues, blood tissues, skin tissues, nerve tissues)

System - Consist of a group of organs working together to carry out the same function

Lets watch a video that desribes the 11 systems found in our body. Please click on the below link

Organisation of Cells in the Human Body