Answer: The answer is crystallization
Explanation:
The correct answer is: d) begins later in life
Eggs or female reproductive cells are formed well before birth in a huge number (primordial oocytes). But, the number of oocyte decreases after birth constantly (there are 2 million oocytes at birth and 40,000 of them in puberty). At menopause, no egg cells are left.
On the other hand, the first sperms are formed only from puberty, but the production of those cells never stops.
Answer:
The area under a speed-time graph represents the distance travelled.
Organisms that originated in a certain geographic region and can only be found in that region are said to be endemic.
Explanation:
Endemic organisms are taxonomic species (plants and animals) which originates and distributed only in specific geographic regions. This state of evolution is called endemism.
They are said to be native or indigenous to that particular region which can be an ecological habitat, an entire nation, an island, a mountain range etc. Certain parts are known for majority of their species being endemic like St. Helen Island, New Caledonia Island, Hawaiian Islands, Southern regions of Africa, and Australia.
The species becomes endemic to a particular region because of the presence of certain bio-geographical environmental qualities of that habitat which are favorable to that species.
When these conditions become unfavorable, then species becomes restricted leading to endangerment or extinction of the species.
Examples:
- Kangaroo - Australia
- Nilgiri Tahr, - Nilgiri Hills, India
- The Redwood trees of West Coast of the USA
- Plants like kalo, sumac of Hawaii