Hearing gives an animal advantages such as being able to listen out for predators, so the animal can run away. The hearing can aid the animal when hunting for other animals, because it can stay still and wait for the right timing to attack, etc.
Answer:
One of the characteristic feature of the phospholipid bi- layer is that like dissolve likes.Therefore,polar molecules and compounds pass though the hydrophllic heads,while non-polar lipid soluble substances pass through the hydrophobic tail,but can not diffuse across the head.
The plasma membrane is amphipathic.It is made up of the hydrophilic heads and hydrophobic tails
Cortisol is made of lipid.Therefore,it will diffuse easily across the bi layer of the plasma membrane though the tail,while LH and Epinephrine,will not diffuse across this hydrophobic barriers,since they are made up of polar molecules.
Explanation:
The correct answer for the question is B. Fossil.
Fossils are remnants, traces of animals or plants, from the past ages that have been preserved. Fossils may be classified as cast and mold fossil, insect preserved in amber, petrified wood, compression fossil of a fern and pyritized ammonite.
Population of older female elephants different from the younger female elephants is described below.
Explanation:
- THE OLDEST ELEPHANTS wandering Mozambique’s Gorongosa National Park bear the indelible markings of the civil war that gripped the country for 15 years: Many are tuskless. They’re the lone survivors of a conflict that killed about 90 percent of these beleaguered animals, slaughtered for ivory to finance weapons and for meat to feed the fighters.
-
Hunting gave elephants that didn’t grow tusks a biological advantage in Gorongosa. Recent figures suggest that about a third of younger females—the generation born after the war ended in 1992—never developed tusks. Normally, tusklessness would occur only in about 2 to 4 percent of female African elephants.
- New, as yet unpublished, research she’s compiled indicates that of the 200 known adult females, 51 percent of those that survived the war—animals 25 years or older—are tuskless. And 32 percent of the female elephants born since the war are tuskless.
- A male elephant’s tusks are bigger and heavier than those of a female of the same age, says Poole, who serves as scientific director of a nonprofit called ElephantVoices. “But once there’s been heavy poaching pressure on a population, then the poachers start to focus on the older females as well,” she explains. “Over time, with the older age population, you start to get this really higher proportion of tuskless females.”
- “The prevalence of tusklessness in Addo is truly remarkable and underscores the fact that high levels of poaching pressure can do more than just remove individuals from a population,” says Ryan Long, a behavioral ecologist at the University of Idaho and a National Geographic Explorer. The “consequences of such dramatic changes in elephant populations are only just beginning to be explored.”
- keystone species is the correct answer.
<u>keystone species</u> which keeps the number of other animal population in
control and low in the entire ecosystem. They play an important role
through this process and helps the food chain effectively.
dominant species - most common species; found often in the ecosystem.
invasive species - which fights for itself survival and can cause harm to
ecosystem. non-native to an ecosystem
