Lab 7: Life on land Part 1 Flashcards
What are the two main groups of mammals living today
Placental
Marsupial
Bear live young and wickedly their young with milk afterbirth
Compared with reptiles, mammals have a higher _______, _______, ______ and ______
Higher metabolic rate
Higher level of activity
Endothermy
More complex behaviour
Key differences between mammals and reptiles
-suckling of young with milk produced by modified skin glands called mammary glands
-evolution of a secondary palate, muscular tongue and heterodont dentition which permit mechanical breakdown of food in mouth
-shift in position of the jaw articulation from the Quadrate and articular to the dentary and squamosal and transformation of the quardrate and articular into ossicles of middle ear
-circulatory, respiratory, excretory, digestive and nervous systems have all been modified to support a higher metabolic rate
Mammalian tail function
Balancing organs, insect squatters, social signals or lost as in humans and apes
Pectoral appendage of mammals consists of what parts
Pelvic appendage consists of what parts
Brachium, antebrachium, manus
Femur, crus, pes
The medial tow of the manus (thumb equivalent) is ______ in many animals such as the cat and the ____ digit of the pes (big toe equivalent) is ____
Reduced
Lost
The mouth of mammals is bounded by fleshy lips called ___
Labia
Rhinarium
Bare, moist patch of skin on the nose which holds the Nares
Outer eye parts of mammals
Upper and lower moveable eyelids
Nictitating membranes (corner to cleanse and moisten eye)
Prominent external flap called the ______ forms the external ear and the auditory canal leads from its base to the head
The ear drum ________ is located where
Auricle
Tympanum - the base of the canal but is too deep to see externally
Mammary glands external parts
4-5 paired rows of nipples called papillae mammae or teats on the thorax of the abdomen
In females and males (remnant)
Two cloacal openings of females
Anus-dorsal opening
Urogenital sinus (vaginal vestibule)-ventral to the anus. Both the urethra and the vagina empty into the vaginal vestibule.
In the male, Urogenital ducts empty through the ____
In non-neutered males, the _______ are located in the sac shaped _____.
Penis
Testes
Scrotum
The entire area including the anus and external genitalia in both males and females is called the _________
Perineum
Claws
Where are they derived and what are they homologous to
Epidermal derivative in mammals that are homologous to primate nails and ungulate hooves
Foot pads
Integumentary structure of mammals composed of thicker stratum corneum
The head skeleton of mammals consists of…..
- Chondrocranium which encloses the brain and is composed of endodermal bone
- Dermal bone, which covered most of the chondrocranium
- Visceral skeleton which are endodermal bony remnants of the visceral arches of fish
In mammals, the nasal cavities have enlarged and the nasal capsules have ossified as the nasal __________ or ______
Conchae or turbinate bones
Increase surface area in the nose in order to clean and warm inspired air
Turbinate bones are homologous to the cartilaginous nasal capsule of primitive terrapods
What pathway allows animals to breathe while manipulating food in the mouth
Air flows dorsal to the secondary palate, through the nasopharynx, out the choanae at the back of the pharynx and into the glottis
Hard palate is formed from extensions of the following bones:
-incisive bone=premaxilla
Incisive bone bears 3 incisor teeth for nipping and cutting
-maxilla
Forms cranial part of the zygomatic arch
-paired palatine
Gives off the pterygoid process
A new jaw joint in mammals was established at the ______-_______ union
Dentary-squamosal
Quadrate and articular became involved in ________ and took up a position in the middle ear cavity as the ____ and _____
Sound transmission
Incus
Malleus
