Upload
aimorales
View
1.140
Download
0
Tags:
Embed Size (px)
Citation preview
TIPOS DE ESTÍMULOS DETECTADOS POR LOS ANIMALES
temperatura
presión
luz
sonido
Otros organismos
Físicos Bióticos
sales
pollutants
agua
Quimicos
REPRODUCTION IN ANIMALS
• Asexual reproduction involves only one parent that produces two or more genetically similar organisms. It occurs mainly in organisms with a simple structure.
• Sexual reproduction involves two parents. A male sex cell joins with a female sex cell (fertilization) and they form a new cell called a zygote. The zygote grows into a new organism.
Budding
Fragmentation
SEXUAL REPRODUCTION
• Two parents of different sex are involved.• The offspring are different from their
parents and from each other
Gonads produce sexual cells.• The gonads in males are the testicles.• The gonads in females are the ovaries.
Sexual cells or gametes.• Ova or eggs, from the ovaries• Sperm cells, from the testes.
MALE FEMALE
GONADS Testicles Ovaries
GAMETES Spermatozoid ovule
GAMETES SIZE Small big
GAMETES SHAPE flagelle
MOBILE GAMETES? Yes no
TYPES OF FERTILIZATIONInternal fertilization •It occurs in terrestrial animals.•The male introduce sperm cells in the female’s body (copulation). •Sperm cells and ova join inside the mother
External fertilization • Occurs in some animals living in water. • The female releases a large amount of ova.• The male releases the sperm cells. • Sperm cells join ova by chance.
EMBRYONIC DEVELOPMENT
Oviparity. Oviparous lay eggs.
EMBRYONIC DEVELOPMENT
Vivipary. The embryo develops inside the body of the mother.
Ovoviviparity. The embryo develops within eggs that remain within the mother's body up until they hatch.