Mammals overview Flashcards
Mammals belong to what taxonomic class?
Mammalia
List and explain the 6 distinguishing characteristics of mammals.
- hair
- muscular diaphragm
- inner ear bones
- larynx
- cervical vertebrae
- mammary glands
Define endotherms in mammals
body generates body heat internally
Define homeotherms in mammals
mammals can cool off by evaporation and heat up by increasing metabolism
What is a typical mammal body temperature?
100 F
Explain hibernation
the lowering of the body temperature and metabolism to save energy during long periods when no food is available
Explain daily torpor
they can lower their body temperature during sleep to save energy
Explain Estrus
In heat to mate
Explain Endometrium
lining of the uterus
Explain Gestation
pregnancy time
Explain Menstrual cycle
the endometrium becomes ready for implantation and sheds if it doesn’t happen
Explain Uterus
Where fertilization takes place
Explain Placenta
where the fetus gets nourishment
What is altricial?
naked, blind and helpless
What is precocial?
eyes open, with hair, able to move
What is heterodont?
different types of teeth for different functions
What is homodont?
only one kind of tooth
What are the 4 types of mammal teeth?
Incisors, Canine, Premolars, Molars
What do the incisors do?
- front teeth
- used for cutting pieces of food
What do Canines do?
- behind the incisors
- used to hold on to prey
- used to tear and slice
What do Premolars do?
- Behind the canines
- flattened for grinding, cutting and shearing
What do Molars do?
flattened for crushing
What is a dental formula and what is it used for?
- numbers of teeth expressed in a numerical formula
- useful for identification
Properly write out a dental formula.
I3/3C1/1CK6/7x2=41
What is a diastema?
no canine pace between teeth
List the functions of mammal hair.
- Insulation
- protects
- receives sensations
- communication
What are the 4 types of mammal hairs?
- Guard hairs
- vibrissae
- awn
- down hair
Which hair is the outer layer?
Guard hairs
Which hair is used for insulation?
- Awn
- Down hairs
Which hairs are whiskers?
Vibrissae
What pigment gives mammals their color?
melanin
What is melanism?
having excess black pigment
What is albinism?
genetic mutation that causes no pigment