Chapter 7
Structural Organization in Animals
Q1. Answer in one word or one line.
i. Give the common name of Periplanata americana.
ii. How many spermathecae are found in earthworm?
iii. What is the position of ovaries in cockroach?
iv. How many segments are present in the abdomen of cockroach?
v. Where do you find Malpighian tubules?
Answer:
i. Cockroach is the common name of Periplanata americana.
ii. 4 pairs of spermathacae are found in earthworm.
iii. The ovaries lie laterally in the 2nd – 6th abdominal segments.
iv. 10 segments are present in the abdomen of cockroach.
v. Malpighian tubules are found at the junction of midgut and hindgut of cockroach.
Q2. Answer the following:
i. What is the function of nephridia?
ii. How many types of nephridia are found in earthworm based on their location?
Answer:
i. Nephridia regulate the volume and composition of the body fluids. A nephridium starts out as a funnel that collects excess fluid from coelomic chamber. The funnel connects with tubular part of the nephridium which delivers the wastes via a pore to the surface in the body wall into the digestive tube.
ii. Three types of nephridia are found in earthworm based on their location.
Q3. Draw a labelled diagram of the reproductive organs of an earthworm.
Answer:
Q4. Draw a labeled diagram of alimentary canal of a cockroach.
Answer:
Q5. Distinguish between the followings
a. Prostomium and peristomium
b. Septal nephridium and pharyngeal nephridium
Answer:
a. Prostomium is present on the ventral mouth of a earthworm which is a lobe that serves as a covering for the mouth whereas peristomium is the first segment of earthworm with a ventral mouth.
b. Septal nephridia are found on both the sides of inter segmental septa of segment 15 to the last that open into intestine whereas pharyngeal nephridia present as three paired tufts in the 4th, 5th and 6th segments.
Q6. What are the cellular components of blood?
Answer: The cellular components of blood are plasma, red blood cells (RBC), white blood cells (WBC), and platelets.
Q7. What are the following and where do you find them in animal body.
a. Chondrocytes
b. Axons
c. Ciliated epithelium
Answer:
a. Chondrocytes are enclosed in small cavities within the matrix secreted by cartilage. They are found in the cartilage.
b. Axon is a long fibre, the distal end of which is branched. It transmits nerve impulses away from the cell body. It is a part of neural tissue.
c. Ciliated epithelium is those when the columnar or cuboidal cells of columnar and cuboidal epithelium bear cilia on their free surface. It is the part of an epithelial tissue.
Q8. Describe various types of epithelial tissues with the help of labelled diagram.
Answer: Epithelial tissue is of two types: simple and compound epithelium.
Simple epithelium is composed of single layer of cells and functions as a lining for body cavities, ducts, and tubes. Simple epithelium is further divided into squamous, cuboidal, and columnar on the basis of structural modification of the cells.
Compound epithelium is made of more than one layer of cells and thus has limited role in secretion and absorption. The main function is to provide protection against chemical and mechanical stresses.
Q9. Distinguish between
a. Simple epithelium and compound epithelium
b. Cardiac muscle and striated muscle
c. Dense regular and dense irregular connective tissues
d. Adipose and blood tissue
e. Simple gland and compound gland
Answer:
a.
| Simple epithelium | Compound epithelium |
| Simple epithelium is composed of single layer of cells and functions as a lining for body cavities, ducts, and tubes | Compound epithelium is made of more than one layer of cells and function is to provide protection against chemical and mechanical stresses. |
b.
| Cardiac muscle | Striated muscle |
| It is a contractile tissue present only in the heart. | It is a tissue which is closely attached to skeletal bones. |
c.
| Dense regular connective tissue | Dense irregular connective tissue |
| The collagen fibres are present in rows between many parallel bundles of fibres. | Fibroblasts and many fibre are present that are oriented differently. |
d.
| Adipose tissue | Blood tissue |
| Adipose tissue is specialised to store fats. | It helps in the transport of various substances. |
e.
| Simple gland | Compound gland |
| This gland have single, unbranched duct. | This gland has branched. |
Q10. Mark the odd one in each series:
a. Areolar tissue; blood; neuron; tendon
b. RBC; WBC; platelets; cartilage
c. Exocrine; endocrine; salivary gland; ligament
d. Maxilla; mandible; labrum; antennae
e. Protonema; mesothorax; metathorax; coxa
Answer:
a. Neuron
b. Cartilage
c. Ligament
d. Antennae
e. Coxa
Q11. Match the terms in column I with those in column II:
Column I Column II
a. Compound epithelium i. Alimentry canal
b. Compound eye ii. Cockroach
c. Septal nephridia iii. Skin
d. Open circulatory system iv. Mosaic vision
e. Typhlosole v. Earthworm
f. Osteocytes vi. Phallomere
g. Genitalia vii. Bone
Answer:
a. Iii
b. Iv.
c. v.
d. ii.
e. i.
f. vii.
g. vi.
Q12. Mention briefly about the circulatory system of earthworm.
Answer: The circulatory system is made of blood vessels, capillaries, and heart. Due to closed circulatory system, blood is confined to the heart and blood vessels. Contractions keep blood circulating in one direction. Smaller blood vessels supply the nerve cord, gut, and the body wall. Blood glands are found on the 4th, 5th and 6th segments. They produce blood cells and haemoglobin. Blood cells are phagocytic in nature.
Q13. Draw a neat diagram of digestive system of frog.
Answer:
Q14. Mention the function of the following
a. Ureters in frog
b. Malpighian tubules
c. Body wall in earthworm
Answer:
a. Ureters in frog act as carrier of sperms and ova.
b. Malpighian tubules carried out excretion in cockroach.
c. The various muscle layers of the body wall in earthworm provide strength and rigidity.
Dipannita Das
Post Id: DABP001104
