« previous next »

Author Question: What is the single unique characteristic that distinguishes extant birds from ot (Read 556 times)

federox

  • Sr. Member
  • ****
  • Posts: 308
on: Aug 8, 2013
What is the single unique characteristic that distinguishes extant birds from other extant vertebrates?
A) endothermy
B) feathers
C) an amniotic egg
D) flight
E) a four-chambered heart


theo

  • Hero Member
  • *****
  • Posts: 698
Reply #1 on: Aug 10, 2013
E) a four-chambered heart
Answer has to be B, 100% :D


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Only 12 hours after an egg cell is fertilized by a sperm cell, the egg cell starts to divide. As it continues to divide, it moves along the fallopian tube toward the uterus at about 1 inch per day.

Did you know?

Allergies play a major part in the health of children. The most prevalent childhood allergies are milk, egg, soy, wheat, peanuts, tree nuts, and seafood.

Did you know?

Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.

Did you know?

Limit intake of red meat and dairy products made with whole milk. Choose skim milk, low-fat or fat-free dairy products. Limit fried food. Use healthy oils when cooking.

Did you know?

The liver is the only organ that has the ability to regenerate itself after certain types of damage. As much as 25% of the liver can be removed, and it will still regenerate back to its original shape and size. However, the liver cannot regenerate after severe damage caused by alcohol.

A single-gene model explains Mendel’s ratios A single-gene model explains Mendel’s ratios
Psoriasis. This photograph demonstrates the characteristic white skin patches of this condition. Psoriasis. This photograph demonstrates the characteristic white skin patches of this condition.
When teenagers live in single-parent homes, a good relationship with grandparents is related to ... When teenagers live in single-parent homes, a good relationship with grandparents is related to ...
Births to Single Mothers Births to Single Mothers
(a) The characteristic karyotype of Klinefelter syndrome. (b) The young man (left) in these photos h (a) The characteristic karyotype of Klinefelter syndrome. (b) The young man (left) in these photos h
The effects of a single crossover in a paracentric inversion heterozygote The effects of a single crossover in a paracentric inversion heterozygote
Video: Types of Transport - Uniport, Antiport and Symport (Glucose and Na+K+ Transporters)

For a complete list of videos, visit our video library