mammalian organization

Question 1

what is a mammal

Answer 1

any member of the group of vertebrate animals in which the young are nourished by milk from special mammary glands of the mother

Question 2

mammals are exceedingly diverse in size,for example

Answer 2

kitti’s hog nosed bat-1.5g
blue whale -100 tons

Question 3

origin of mammals

Answer 3

mesozoic era

Question 4

age of mammals

Answer 4

cenozoic era

Question 5

mammals were evolved from a

Answer 5

synapsid reptilian ancestor

Question 6

mammals lived in mesozoic era were somewhat insignificant.limited fossil evidence suggested that they were

Answer 6

conservative mouse-like form and
* Had quadrupedal locomotion

Question 7

what are the 4 eras

Answer 7

pre cambrian
paleozoic
mesozoic
cenozoic

Question 8

giraffe horns are called as

Answer 8

ossicones

Question 9

3 pairs of salivary glands in mammals

Answer 9

parotid
sub mandibular
sublingual

Question 10

lobules are absent in lungs of

Answer 10

whales,horses and some bats

Question 11

accessory glands present in male reproductive system

Answer 11

cowper’s glands
prostrate glands
seminal vesicles

Question 12

epididymis for

Answer 12

physiological maturation of sperms

Question 13

types of the uterus in mammals

Answer 13

duplex
simplex
bicornate
bipartite

Question 14

a single reproductive cycle is known as

Answer 14

estrous cycle

Question 15

conditions of newborns

Answer 15

Precocial – well developed
Altricial – poorly developed

Question 16

limb modification in mammals

Answer 16

1. Reduction of area touches with the
   ground
2. Elongation of distal ends of the limbs
3. Reduction or increase of the number of joints
4. Centralization of force and reduction of
   the number of digits
5. Fusion of bones

Question 17

corpus callosum cannot be seen in

Answer 17

monotremes

Question 18

marsupials born within

Answer 18

8 to 30 days

Question 19

modern placentals derived from

Answer 19

small nocturnal insectivorous or omnivorous animal in cretaceous period

Question 20

evolutionary trends of eutherians

Answer 20

1.larger body size
2.limbs became larger and specialized foe locomotion
3.further development of brain
4.teeth were reduced in number and became specialized

Question 21

Chemicals extracted from shrew venom may be potentially useful in the treatment of

Answer 21

1.High blood pressure
2.Neuromuscular diseases and migraines
3.Treating ovarian cancer (peptide- soricidin)

Question 22

Hedgehogs have some natural immunity against snake venom due to the

Answer 22

protein erinacin in the animal’s
muscular system

Question 23

some families of order Insectivora

Answer 23

1.Erinacidae
2.Soricidae
3.Talpidae`

Question 24

ant-eating eutherian orders

Answer 24

order pholidota-pangolian
order edenata-ant eaters and sloths
order tubulidenata-Aadwark

Question 25

animals under order edenata

Answer 25

sloth
giant ant eater
armadillo

Question 26

what are the primitive characters present in gnawing mammals

Answer 26

1. Long low skull
2. small brain
   3.small cerebral hemispheres
   4.pentadactyl limb
   5.separate ulna and radius

Question 27

largest rodent

Answer 27

capybara

Question 28

modifications of mouth parts in rodents

Answer 28

1.large masseter muscle-forward and backward movement
2.mandibles are not united, freely movable
3.jaw muscles are large
4.food is passed twice through the gut
5.2nd incisors, canines and anterior pre molars are absent

Question 29

similarities between rodents and lagomorphs

Answer 29

diastema
cheek pouches
ceacotrophy

Question 30

adaptaions of bats for production and emmision of sound waves

Answer 30

1.large larynx
2.cricothyroid muscle
3.Special resonating chamber
to modulate the frequency
4.Face modified to beam the sound waves
Eg. form a leaf-nose

Question 31

what are the modifications found in bats for protecting their ears from their own sound

Answer 31

1.Tensor tympani muscle
– change the tension of tympanic membrane
2.Stapedius muscle
– change the angle at which stapes contact the oval window

Question 32

carnivores originated in

Answer 32

paleocene time,herbivores and carnivores both show parallel evolution and adaptive radiation

Question 33

carnassial teeth are made up of combining

Answer 33

4th pre-molar and 1st molar