Frank Solutions for Chapter 18 Structure and Function of Skin Class 9 Biology ICSE
Exercise
1. Name the following:
(a) Outer nonvascular layers of the skin.
(b) Innermost germinative layer of the epidermis.
(c) Outermost nonliving layer of the epidermis.
(d) Inner thick vascular region of the skin.
(e) Gland which secretes sweat.
(f) The milk secreting glands.
(g) Gland which secretes wax.
(h) The nails are modified.
(i) The colour of the skin is due to.
(a) Outer nonvascular layers of the skin.
(b) Innermost germinative layer of the epidermis.
(c) Outermost nonliving layer of the epidermis.
(d) Inner thick vascular region of the skin.
(e) Gland which secretes sweat.
(f) The milk secreting glands.
(g) Gland which secretes wax.
(h) The nails are modified.
(i) The colour of the skin is due to.
Answer
(a) Stratum corneum, transitional region, stratum germinativum
(b) Stratum germinativum
(c) Stratum corneum
(d) Dermis
(e) Sweat gland/sudoriferous gland
(f) Milk glands/mammary glands
(g) Wax gland
(h) Epidermis
(i) Melanin
(b) Stratum germinativum
(c) Stratum corneum
(d) Dermis
(e) Sweat gland/sudoriferous gland
(f) Milk glands/mammary glands
(g) Wax gland
(h) Epidermis
(i) Melanin
2. Complete the following statement by choosing the correct alternative:
(a) The skin is thickest on the ______. (soles, palms, finger, face).
(b) Human skin has distinctive regions ______. (nephron and malpighian, epidermis and dermis, median and inner sole and palm).
(c) The outermost dead layer of epidermis is ______. (stratum germinativum, transitional zone, stratum corneum).
(d) The cytoplasm of uppermost layer of the epidermis is filled with ______. (keratin, melanin, intermedin, insulin).
(e) Dermis of the skin is derived from ______. (ectoderm, mesoderm and endoderm).
(f) Beneath the dermis is a layer of ______. (fatty tissue, vascular tissue, loose connective tissue).
(g) Milk gland is a modified ______. (oil gland, sweat gland, meibomain gland).
Answer
(a) The skin is thickest on the ______. (soles, palms, finger, face).
(b) Human skin has distinctive regions ______. (nephron and malpighian, epidermis and dermis, median and inner sole and palm).
(c) The outermost dead layer of epidermis is ______. (stratum germinativum, transitional zone, stratum corneum).
(d) The cytoplasm of uppermost layer of the epidermis is filled with ______. (keratin, melanin, intermedin, insulin).
(e) Dermis of the skin is derived from ______. (ectoderm, mesoderm and endoderm).
(f) Beneath the dermis is a layer of ______. (fatty tissue, vascular tissue, loose connective tissue).
(g) Milk gland is a modified ______. (oil gland, sweat gland, meibomain gland).
Answer
(a) soles
(b) epidermis and dermis
(c) stratum corneum
(d) keratin
(e) mesoderm
(f) loose connective tissue
(g) sweat gland
(b) epidermis and dermis
(c) stratum corneum
(d) keratin
(e) mesoderm
(f) loose connective tissue
(g) sweat gland
3. Mention whether the following statements are true or false:
(a) Skin is the largest organ of the body.
(b) Skin area is about 2 square metres.
(c) Stratum corneum is a layer of epidermis.
(d) Dermis is a thick vascular region of the skin.
(e) Hair is not the characteristics feature of the mammal.
(f) Meibomian glands are modified sweat glands.
Answer
(a) True
(b) True
(c) True
(d) True
(e) False
(f) False
(b) True
(c) True
(d) True
(e) False
(f) False
4. Every question has four options. Choose the correct answer:
(i) Innermost layer of epidermis is called
(a) stratum malpighi
(b) transitional zone
(c) stratum corneum
(d) none
Answer
(a) stratum Malpighi
(ii) Thickest epidermis is found on
(a) eyelid
(b) thigh
(c) lip
(d) palm
Answer
(d) palm
(iii) Horny layer is also called as
(a) Malpighian layer
(b) stratum corneum
(c) stratum lucidum
(d) none
Answer
(b) stratum corneum
(iv) The vascular region of the skin is called
(a) epidermis
(b) dermis
(c) Malpighian layer
(d) none
Answer
(b) dermis
(v) Sweat glands are situated in
(a) epidermis
(b) dermis
(c) both
(d) none
Answer
(b) dermis
(vi) Milk glands are modified
(a) sweat gland
(b) rectal gland
(c) perineal gland
(d) none
Answer
(a) sweat gland
(vii) When a person feels cold, the blood vessels
(a) dialate, and the sweat glands are inactive
(b) dialate and the sweat glands are active
(c) constrict and the sweat glands are inactive
(d) constrict and the sweat glands become active
Answer
(c) constrict and the sweat glands are inactive
(c) constrict and the sweat glands are inactive