. ___________ is a bird with a rare but not unheard-of plumage variation, such as very light or very black plumage, which is commonly a sign of leucism or melanism.

The most exotic birds like _________ use these metabolic pathways to change the structure of carotenoids and lead to produce porphyrins.

1. Owls
2. Pigeons
3. Turacins
4. Ducks

__________ plumage is notably prevalent in raptors and gulls, both of which can take up to three years to mature.

1. Juvenile 
2. Natal
3. Subadult
4. Basic

_____________ is also known as winter plumage or non-breeding plumage.

1. Basic plumage
2. Nuptial plumage
3. Natal plumage
4. Juvenile plumage

______________ is a condition in which a bird's head feathers or other patches are removed during a molt or as a result of injury or disease.

1. Leucism
2. Hybrid
3. Baldness
4. Albinism

______________ have less distinct plumage until they reach adulthood.

1. Young birds
2. Immature birds
3. Adult
4. Eggs

___________is the process of regrowing feathers.

1. Mating
2. Molting
3. Breeding
4. None of the above

The color of the natal plumage is usually basic, and they function to ___________ the young one.

1. Insulate
2. Camouflage
3. Insulate and camouflage
4. Attract

___________ are the same chemicals that give humans their various skin tones and colors.

1. Melanin
2. Carotenes
3. Porphyrins
4. Chlorophylls

Embryo development in _______________ animals, on the other hand, occurs within the female member of that species.

1. Viviparous
2. Wild animals
3. Oviparous
4. Aquatic animals

Fertilization occurs after gametogenesis and before embryogenesis.

1. True
2. False

The given image explains external fertilization.

1. True
2. False

Only a single parent is involved in sexual reproduction.

1. True
2. False

1. Across: 3 – Oviparous, 4 – Zygote Down: 1 - Fertilization, 2 – Embryo
2. Across: 3 – Embryo, 4 – Fertilization Down: 1 - Oviparous, 2 – Zygote
3. Across: 3 – Zygote, 4 – Embryo Down: 1 - Fertilization, 2 – Oviparous
4. Across: 3 – Oviparous, 4 – Fertilization Down: 1 - Zygote, 2 – Embryo

__________ is a process in which two parents take part in producing the young one.

1. Asexual reproduction
2. Binary fission
3. Sexual reproduction 
4. Fragmentation