Lesson 25b: The Reptiles (Chordates p2)

Question 1

What are 3 characteristics of reptiles?

Answer 1

A. Scales

1. Reptiles have dry skin covered with waterproof scales.
2. Their scales:
   
   • Preserve body moisture.
   • Epidermal scales arise from the skin, but are not living tissue
   • Do not grow, so the animal will molt their scales when new scales have developed
3. Reptiles shed skin and scales in one piece several times a year.

B. Ectothermic
(((1. In hot climates, they stay underground or in shady areas during the day.
2. In cold climates, they hibernate in the winter.)))

C. Are either tetrapods, or have no legs

Question 2

Explain a reptiles respiratory system…

Answer 2

They have efficient lungs for respiration

Question 3

Explain how reptiles reproduce sexually…

Answer 3

Males and females of a species mate and fertilization occurs internally

a) The zygote is encased in a leathery shell providing protection, as well as allowing for gas exchange

b) Then, most reptiles lay their eggs
(1) Oviparous: eggs are hatched after they’ve been laid by the parent
(2) Ovoviviparous: eggs are hatched inside the parent

Question 4

How can certain reptiles reproduce non-sexually?

Answer 4

They typically reproduce sexually, with a few exceptions:

1. Species of lizards reproduce asexually via parthenogenesis
   a) Eggs develop into embryos without fertilization
   b) Entire species is female, no males are present
2. Some species can reproduce both sexually and asexually, such as the Komodo Dragon

Question 5

Explain how the eggs of reptiles function…

Answer 5

a) Embryo is surrounded by an amnion that holds fluid to protect and cushion the embryo
b) Embryo is nourished by a yolk sac as it grows

c) Many reptiles rely on temperature dependent sex determination
- sex is determined by environmental temperature during the embryonic period of development.

file:///C:/Users/trgan/Sync/LisA%20school/reptiles%20eggs%20pic.png

Question 6

Tell me about order Sphenodontia…

Answer 6

1. One living species in this order: the tuatara
2. Lives over 100 years
3. Nocturnal
4. Does not have external ears
5. Third eye located on the top of the head, used for sensing light

file:///C:/Users/trgan/Sync/LisA%20school/Reptiles-%20Order%20Sphenodontia.png (((pic of the tuatara)))

Question 7

What is in order Crocodilia?

Answer 7

crocodiles, caimans, alligators, and gharial

Question 8

Explain a reptiles circulatory system…

Answer 8

1. Most reptiles have a 3-chambered heart with 2 atria and 1 ventricle.
2. Order Crocodilia has a 4-chambered heart.

file:///C:/Users/trgan/Sync/LisA%20school/3%20and%204%20chambered%20hearts.mp4

Question 9

Tell me about order Crocodilia…

Answer 9

1. Semi-aquatic
2. Predators
3. All have similar body structures:
   - elongated snout,
   - powerful jaws,
   - muscular tail,
   - large, protective, non-overlapping scales,
   - streamlined body,
   - and eyes and nostrils that are positioned on top of the head
4. 4-chambered heart

Question 10

What is in order Squamata?

Answer 10

Snakes and lizards

Question 11

Tell me about snakes in order Squamata…

Answer 11

a) Move by throwing their body side to side, known as sidewinding
b) Suffocate and drown prey
c) Some snakes eat eggs, while others eat small prey

Question 12

Tell me about lizards in order Squamata?

 - What is their size range?
 - What is in order Squamata?

Answer 12

a) Range in size from a few centimeters in length to over 10 ft long
b) Includes iguanas, horned lizards, collared lizards, chameleons, and whiptails

Question 13

What are 4 differences between snakes and lizards (Order Squamata)?

Answer 13

a) Lizards have 2 pairs of limbs, snakes have none.
b) Lizards have ears and can hear, snakes are deaf.
c) Lizards have the same type of scales over their entire body, where as snakes have specialized scales on their bellies for locomotion.
e) Lizards have eyelids, and are able to close their eyes, whereas snakes do not have eyelids.

Question 14

Tell me about order Testudines (class reptile)…

Answer 14

1. Includes turtles and tortoises
2. Turtles typically live in the water, while tortoises typically live on land
3. They have a hard shell

Question 15

Tell me about a turtle’s and tortoise’s hard shell (order Testudines)…

Answer 15

a) Their upper shell composed of bony plates is called a CARAPACE
b) Their lower shell is called a PLASTERON
c) Shells are part of the animal’s skeleton
d) They provide protection for the animal
e) Most members can pull all of their appendages into their shell and close off the opening with little trap doors

Question 16

Lesson 25b: the reptiles (chordates p2) video summary

Answer 16

file:///C:/Users/trgan/Sync/LisA%20school/Lesson%2025b%20Phylum%20Chordata%20P2%20video%20summary.mp4