Answer:
I think it is both 1 and 2
Explanation:
Answer:
Synaptic transmission consists of three steps: (1) intracellular vesicles loaded with neurotransmitters are targeted to the presynaptic membrane; (2) an action potential triggers exocytosis to release the neurotransmitters to the synaptic cleft between two neurons
hope this helps !!!!
Answer:
El híbrido va a ser esteril.
Explanation:
En la cruza entre dos especies distintas, cuando ocurre, existen distintos mecanismos de aislamiento reproductivo, que son barreras que inhiben o interrumpen el flujo génico entre especies distintas. Es decir que no habrá exito reproductivo de estas cruzas. Se trata de caracteres biológicos propios de cada especie que previenen la reproducción con otras especies.
Estos mecanismos de aislamiento reproductivo pueden ser precigóticos o postcigóticos.
1.Pre-copulatorios o pre-cigóticos:
- Ecológico o por aislamiento de hábitat;
- Por incompatibilidad de gametas.
2. Post-copulatorios o cigóticos:
- Inviabilidad del híbrido;
- Híbrido con viabilidad o fertilidad disminuido;
- Interacciones citoplasmáticas.
La mula es producto de la cruza entre dos especies distintas: una yegua (Equus ferus caballus) y un burro (Equus africanus asinus). Es un ejemplo de la accion de mecanismo poscigótico, en el cual se forma un híbrido viable esteril. Este ejemplar puede nacer, crecer y sobrevivir, pero que no puede producir gametas funcionales, por lo cual no puede reproducirse.
Trophic cascades are powerful indirect interactions that can control entire ecosystems
Answer:
Earth's surface didn't look much different. With few exceptions.
The global climate is cooler and drier, and seasonal, similar to modern climates. As the climate began to cool down grasslands continued to expand and forests started to dwindle in extent. In the seas, kelp forests made their first appearance and soon became one of Earth's most productive ecosystems. Water from the Atlantic Ocean poured in through the Strait of Gibraltar to deluge the Mediterranean Basin. The event is called the Zanclean flood. Parts of of southern Norway and southern Sweden that had been near sea level rose to form the Hardangervidda plateau and the South Swedish highlands.
Shorty after, the glaciations, uplift of the Rocky mountains and Panama seaway closure began to reshape the Earth.
Explanation:
