ICSE Living Science Biology for Class 7 Solutions Chapter 2 Organization in Living Beings
Check Your Progress
State if the following statements are true or false. Correct the statement if it is false.
Question 1.
The cell is at the lowest level of biological organization.
Answer:
True
Question 2.
Cells that have similar structure and perform similar functions are organized to form a tissue.
Answer:
True
Question 3.
An organism comprises of various tissues and cell which have the same structure.
Answer:
False. An organ comprises of various tissues and cell which have the same function.
Question 4.
Leaves, flowers, fruits, and roots are various plant tissue.
Answer:
False. Leaves, flowers, fruits, and roots are various plant organs.
Question 5.
Heart, stomach and liver are animal tissues.
Answer:
False. Heart, stomach and liver are animal organs.
A. Tick the most appropriate answer.
Question 1.
Several organs work together in a coordinated manner and form a/an –
a. tissue
b. organ system
c. organ
d. organism
Answer:
b. organ system
Question 2.
A group of living organisms which can reproduce among themselves belongs to the same
a. population
b. community
c. ecosystem
d. species
Answer:
d. species
Question 3.
The number of individual organisms of a particular species living in an area constitute its
a. population
b. community
c. ecosystem
d. biosphere
Answer:
a. population
Question 4.
In a community which of the following is an abiotic component ?
a. Plant
b. Animals
c. Sunlight
d. Insects
Answer:
c. Sunlight
Question 5.
A group of different species living in a specific area forms a
a. species
b. biosphere
c. community
d. population
Answer:
c. community
B. Fill in the blanks.
Question 1
………….. is the structural and functional unit of life.
Answer:
Cell is the structural and functional unit of life.
Question 2.
A …………. is a collection of cells performing a simila function.
Answer:
A tissue is a collection of cells performing a similar function.
Question 3.
A group of tissues which performs a specific function is called a/an
Answer:
A group of tissues which performs a specific function is called an organ.
Question 4.
A group of organ systems working together make up a/an
Answer:
A group of organ systems working together make up an organism.
Question 5.
AH organisms living together in an area make up a/an
Answer:
All organisms living together in an area make up a community.
C. Define these terms.
1. organ system
2. population
3. biotic community
4. biosphere
5. species
6. neuron
7. connective tissue
Answer:
1. organ system – An organ system is a group organs working together to perform a specific function.
2. population – All the members or individuals of a particular species living in a particular area constitute its population.
3. biotic community – The population of all plant and animal species living in a particular area constitute a biotic community.
4. biosphere – The zone on the earth in which all living beings exists is termed as biosphere.
5. species – A group of living organisms which can breed among themselves constitute a species.
6. neuron – The cells that constitute nervous tissue are called neurons or nerve cells.
7. connective tissue – The tissue which connects various tissues together in any organ is called connective tissue.
D. Differentiate between
Question 1.
lower and higher levels of organization.
Answer:
Lower level of organization :
1. The cell is the lowest level of organization in this level
2. Cell to organ system level forms the lower level of organisation.
Higher level of organization :
The species is the lowest level of organization in this level
Population to biosphere forms the higher level of organisation.
Question 2.
population and community.
Answer:
Population :
1. All the members of a particular species living is a particular area constitute a population.
2. Members of same species constitute a population.
Community :
All the organisms living together in an area make up a community.
It is a group of different populations.
Question 3.
community and biosphere.
Answer:
Community :
- All the organisms living together in area constitute community.
- It does not form the highest level of organization.
Biosphere:
- All ecosystems together make up biosphere.
- It is the highest level of organization.
Question 4.
species and population.
Answer:
Species
- A species is a group of living organisms which are veiy closely related to each other and can reproduce among themselves.
- One species can have many populations at different places.
Population:
- A population is a group of all individuals of a particular species living in a given area.
- One population can have only one species.
E. Answer the following in short.
Question 1.
Name the lower levels of organization.
Answer:
Lower levels of organization are :
Cellular level
↓
Tissue level
↓
Organ level
↓
Organ system level Organism
Question 2.
What is a species ?
Answer:
A species is a group of living organisms which can breed among themselves.
Question 3.
Define an organism.
Answer:
An organism is .an individual with an independent identity comprising of many organ system working together in a coordinated manner.
Question 4.
What is an ecosystem ?
Answer:
All living organisms along with the non living organisms of an area forms an ecosystem.
F. Answer the following in detail.
Question 1.
Name different levels of organization in the living world.
Answer:
Levels of organization in the living world are :
Levels of organization in the living world
Question 2.
What are the lower levels of organization ? Explain.
Answer:
Lower levels of organization are :
Cellular level : The lowest level of organization is the cell. A cell is living and can exist independently. In single celled organisms like amoeba, paramecium, yeast etc all functions- of life like digestion, respiration, reproduction and excretion are performed by single cell.
Tissue level : The cells that are similar in structure and functions organize to form a tissue, in multicellular organisms. For example nervous tissue is formed of neurons, muscular tissue is formed of muscle cells and so on. Similarly the plants are also made up of different tissues. For example parenchyma, sclerenchyma etc. The organization of similar cells to form tissues is known as tissue level of organization.
Organ level : Different types of tissues in a living organism organise to form organs which perform a specific function. This is called organ level of organization. Stomach is an organ in human beings, which consists of different types of tissues and perform specific functions. Similarly intestine kidney and brain are other organs that perform specific functions and made up of different types of tissues. In plants leaf, roots, stem, flowers and fruits are different organs, which are made up of different type of tissues.
Organ system level : Many organs work together in a coordinated manner to perform a specific function and form an organ system. Organ system is the next level of organization. For example digestive system has a job of digesting food. Many organs like stomach, intestine, liver and pancreas constitute digestive system. Root and shoot system in plants are the organ systems that perform specific functions and are composed of different organs.
Question 3.
What is the difference between an organ and organ system ?
Answer:
Organ :
1. Different tissues combine to form organs which perform specific functions.
2. Stomach, kidneys, lungs etc. are the different organs of human beings.
Organ System :
Different organs combine to form organ system to perform a specific function.
Digestive system, nervous system etc. are the different organ systems of the human beings.
Question 4.
Describe ecosystem as a level of organization.
Answer:
Several communities comprising populations of various organisms (biotic components) that live together in an area and interact with non-living things (abiotic components) of the environment fomi an ecosystem. The communities in an ecosystem get everything that they need for their sustenance from the ecosystem itself.
Examples : A pond and a forest are natural ecosystems while an aquarium and a garden are artificial ecosystems (man-made).
An ecosystem consists of biotic components (plants, animals, microbes) and abiotic components (soil, air, water, minerals, light, etc) which interact with each other in a particular region.
Living Science Biology Class 7 ICSE Solutions