The C-shaped cartilaginous rings around the trachea are open posteriorly to:

(1) allow for expansion of the esophagus during swallowing 

(2) allow the vocal cords to relax

(3) prevent food from entering the nasal cavity during swallowing

(4) prevent food from entering the trachea

The body cells in cockroach discharge their nitrogenous waste in the haemolymph mainly in the form of

(1) ammonia

(2) potassium urate

(3) urea

(4) calcium carbonate

In male cockroaches,  sperms are stored in which part of the reproductive system?

(1) Seminal vesicles

(2) Mushroom glands

(3) Testes

(4) Vas deferens

Smooth muscles are 

(1) involuntary, fusiform, non-striated

(2) voluntary, multinucleate, cylindrical

(3) involuntary, cylindrical, striated

(4) voluntary, spindle-shaped, uninucleate

Which of the following features is not present in Periplaneta americana?

(1) Indeterminate and radial cleavage during embryonic development

(2) Exoskeleton composed of N-acetylglucosamine

(3) Metamerically segmented body

(4) Schizocoelom as body cavity

The function of the gap junction is to 

1. performing cementing to keep neighbouring cells together

2. faciliate communication between adjoining cells by connecting the cytoplasm for rapid transfer of ions, small molecules and some large molecules

3. seperate two cells from each other

4. stop substance from leaking across a tissue

The terga sterna and pleura of cockroach body are joined by

1. cementing glue

2. muscular issue

3. arthrodial membrane

4. cartilage

Choose the corectly matched pair.

(1) Tendon-Specialised connective tissue

(2) Adipose tissue-Dense connective tissue

(3) Areolar tissue-Loose connective tissue

(4) Cartilage-Loose connective tissue

What external changes are visible after the last moult of a cockroach nymph?

1.  Mandible become harder

2.  Anal cerci develop

3.  Both fore wings and hind wings develop

4.  Labium develops

Compared to those of humans, the erythrocytes in frog are

(1) without nucleus but with haemoglobin

(2) nucleated and with haemoglobin

(3) very much smaller and fewer

(4) nucleated and without haemoglobin