IGCSE Biology Paper-5: Specimen Questions with Answers 29 - 31 of 62

Question 29

Describe in Detail Subjective▾

Starch is a type of carbohydrate present in many of our food Items. Carbohydrates are energy-yielding components of food.

Here three types of food material are given. Identify the presence of carbohydrate

Image Shows Three Types of Food Material
Edit

Explanation

  • To identify the presence of carbohydrate in food material first place the all materials in separate and clean petri plate.
  • Drop out iodine solution to each item (2 - 3 drops) .
  • When we observe all three petri plates
  • Blue-black colour appears on bread slice and potato slice, whereas, chickpea seeds do not show any change in colour.
  • It shows Bread and potato contain starch which gives blue-black in color on addition of iodine solution.
  • Chickpea seeds do not contain starch and thus do not show any change in color.

Passage

An infestation of body lice occurs when a certain type of lice invade the body and clothing. Lice are parasitic organism that feed on human blood and can infest the head, body, and pubic area.

Shows a Given Above Figure is Lice

Question 30 (1 of 3 Based on Passage)

Write in Short Short Answer▾

What are the common recognizing the signs of body lice

Edit

Explanation

  • intense itching (pruritus)
  • allergic reaction to body
  • red bumps on the skin
  • thickened or darkened skin mainly near the waist , if the lice have been there for a long time

Question 31 (2 of 3 Based on Passage)

Write in Short Short Answer▾

Name the class of arthropods to which this animal belongs with reason.

Edit

Explanation

Human lice fall under the phylum Arthropod because of the following features:

  • Triploblastic embryo, which means embryos, have three different types of tissues, the endoderm, mesoderm and ectoderm
  • Segmented bodies.
  • Exoskeleton composed of chitin, providing support and protection.

It belongs from the class Insect