Internal vs External Fertilization Development Fertilization Fertilization is
![Internal vs External Fertilization & Development Internal vs External Fertilization & Development](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-1.jpg)
![Fertilization • Fertilization is the union of egg and sperm – Egg (n) + Fertilization • Fertilization is the union of egg and sperm – Egg (n) +](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-2.jpg)
![External Fertilization • External fertilization occurs outside of female parent – Fish – Amphibians External Fertilization • External fertilization occurs outside of female parent – Fish – Amphibians](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-3.jpg)
![External Fertilization • Produce many eggs in water because: – Eggs are laid in External Fertilization • Produce many eggs in water because: – Eggs are laid in](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-4.jpg)
![Internal Fertilization • Internal fertilization occurs inside the female parent – Reptiles (lay many Internal Fertilization • Internal fertilization occurs inside the female parent – Reptiles (lay many](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-5.jpg)
![Internal Fertilization • Chance of survival is high • Zygote forms inside the female Internal Fertilization • Chance of survival is high • Zygote forms inside the female](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-6.jpg)
![Parthenogenesis • Eggs develop without fertilization – Bees – There are three main categories Parthenogenesis • Eggs develop without fertilization – Bees – There are three main categories](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-7.jpg)
![Hermaphrodites • Hermaphrodites have both male and female reproductive organs – Hydra, snail, – Hermaphrodites • Hermaphrodites have both male and female reproductive organs – Hydra, snail, –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-8.jpg)
![Hermaphrodites • Protandry: When the organism starts as a male, and changes gender to Hermaphrodites • Protandry: When the organism starts as a male, and changes gender to](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-9.jpg)
![Development of the fertilized egg • External Development – Develops outside the parent – Development of the fertilized egg • External Development – Develops outside the parent –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-10.jpg)
![The Egg • Eggs have – Amnion – fluid filled sac (moist, cushion) – The Egg • Eggs have – Amnion – fluid filled sac (moist, cushion) –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-11.jpg)
![Internal Development • Internal Development occurs in mammal inside female 1. Placental – mammals Internal Development • Internal Development occurs in mammal inside female 1. Placental – mammals](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-12.jpg)
![Non-placental Mammals 1. Non-placental – have external development • Marsupials & monotremes egg laying Non-placental Mammals 1. Non-placental – have external development • Marsupials & monotremes egg laying](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-13.jpg)
- Slides: 13
![Internal vs External Fertilization Development Internal vs External Fertilization & Development](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-1.jpg)
Internal vs External Fertilization & Development
![Fertilization Fertilization is the union of egg and sperm Egg n Fertilization • Fertilization is the union of egg and sperm – Egg (n) +](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-2.jpg)
Fertilization • Fertilization is the union of egg and sperm – Egg (n) + Sperm (n) = zygote 2 n
![External Fertilization External fertilization occurs outside of female parent Fish Amphibians External Fertilization • External fertilization occurs outside of female parent – Fish – Amphibians](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-3.jpg)
External Fertilization • External fertilization occurs outside of female parent – Fish – Amphibians – Aquatic vertebrates
![External Fertilization Produce many eggs in water because Eggs are laid in External Fertilization • Produce many eggs in water because: – Eggs are laid in](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-4.jpg)
External Fertilization • Produce many eggs in water because: – Eggs are laid in the water – There is no parental care – Fertilization & development occur outside the female body
![Internal Fertilization Internal fertilization occurs inside the female parent Reptiles lay many Internal Fertilization • Internal fertilization occurs inside the female parent – Reptiles (lay many](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-5.jpg)
Internal Fertilization • Internal fertilization occurs inside the female parent – Reptiles (lay many eggs) – Birds (lay only a few eggs) – Mammals • development takes place inside the female body
![Internal Fertilization Chance of survival is high Zygote forms inside the female Internal Fertilization • Chance of survival is high • Zygote forms inside the female](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-6.jpg)
Internal Fertilization • Chance of survival is high • Zygote forms inside the female body.
![Parthenogenesis Eggs develop without fertilization Bees There are three main categories Parthenogenesis • Eggs develop without fertilization – Bees – There are three main categories](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-7.jpg)
Parthenogenesis • Eggs develop without fertilization – Bees – There are three main categories for honey bees. • The queen is the center of the hive because she is responsible for laying eggs. She mates once and retains the sperm for the rest of her reproductive life. When the queen lays her eggs, she deposits them in different sized receptacle. The smaller cells, about 5 mm in diameter, contain fertilized eggs destined to become sterile female workers. – The larger cells, about 7 mm in diameter, contain future male drones. These eggs are not fertilized, and reproduce via parthenogenesis. –
![Hermaphrodites Hermaphrodites have both male and female reproductive organs Hydra snail Hermaphrodites • Hermaphrodites have both male and female reproductive organs – Hydra, snail, –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-8.jpg)
Hermaphrodites • Hermaphrodites have both male and female reproductive organs – Hydra, snail, – Earthworms are example of hermaphrodite. Although they possess ovaries and testes, they have a protective mechanism against self fertilization and can only function as a single sex at one time. • Sexual reproduction occurs when two worms meet and exchange gametes, copulating on damp nights during warm seasons. Fertilized eggs are protected by a cocoon, which is buried on or near the surface of the ground.
![Hermaphrodites Protandry When the organism starts as a male and changes gender to Hermaphrodites • Protandry: When the organism starts as a male, and changes gender to](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-9.jpg)
Hermaphrodites • Protandry: When the organism starts as a male, and changes gender to a female later in life. – The Clownfish • Generally one anemone contains a 'harem', consisting of a large female, a smaller reproductive male, and even smaller non-reproductive males. • If the female is removed, the reproductive male will change sex and the largest of the non-reproductive males will mature and become reproductive. It has been shown that fishing pressure can change when the switch from male to female occurs, since fishermen naturally prefer to catch the larger fish. • The populations are generally changing sex at a smaller size, due to artificial selection.
![Development of the fertilized egg External Development Develops outside the parent Development of the fertilized egg • External Development – Develops outside the parent –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-10.jpg)
Development of the fertilized egg • External Development – Develops outside the parent – Aquatic development: develops in water. Egg get nutrition from yolk sac. – Terrestrial Development: land development
![The Egg Eggs have Amnion fluid filled sac moist cushion The Egg • Eggs have – Amnion – fluid filled sac (moist, cushion) –](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-11.jpg)
The Egg • Eggs have – Amnion – fluid filled sac (moist, cushion) – Yolk sac – nutrition – Allantois – derived from gut lining. Filled with blood vessels (gas & nutrient exchange **similar to placenta in mammals**) – Chorion – membrane surround embryo yolk sac – Shell – outer covering porous
![Internal Development Internal Development occurs in mammal inside female 1 Placental mammals Internal Development • Internal Development occurs in mammal inside female 1. Placental – mammals](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-12.jpg)
Internal Development • Internal Development occurs in mammal inside female 1. Placental – mammals that possess an internal structure that forms joining of embryo and mother (mice, cats dogs, whale, human) • • Allows for longer internal development Exchange of O 2, CO 2 & nutrients between mother and embryo
![Nonplacental Mammals 1 Nonplacental have external development Marsupials monotremes egg laying Non-placental Mammals 1. Non-placental – have external development • Marsupials & monotremes egg laying](https://slidetodoc.com/presentation_image_h2/f7b13e1aed445414ef489febbbda67d9/image-13.jpg)
Non-placental Mammals 1. Non-placental – have external development • Marsupials & monotremes egg laying mammals