A. appearances B. imitating C. distinguish D. isolate E. advantageous F. diverse G. identical H. criterion I. markings J. poisonous K. threatening |
Why different species start looking exactly the same
Is it better to stand out from the crowd or be similar to the background? For birds, the answer is complicated. While peacocks(孔雀) show off their brightly colored feathers to attract mates and ward off predators(捕食者), other birds find it
Groups of birds flying together often come from the same species, making it hard to
“In imitation, you often want to look like something because there’s an advantage to being that other thing. You want species to think you’re
While it may not seem like it at first, imitating other birds is helping to create more
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A. hiding B. viewing C. fed D. immediately E. enabled F. figure G. largely H. attack I. prefer J. balancing K. fit |
If you have ever had a cat, or have watched one of the many funny cat videos online, you'll know that cats have a mind of their own. A lot of the things they do are hard to understand—they like to climb up tall furniture,
Now scientists have managed to
According to Tony Bufflington, a veterinarian and professor at Ohio State University in the US, cats' strange behavior
"Cats today still have many of the same instincts that
In the wild, cats are hunters. Their bodies and great
cats' hunting instinct is also what makes them
However, cats can also be prey. This explains why they like to stay in small spaces like drawers or washing machines—they are
But knowing how cats' minds work is not only useful for better understanding them. It may also help cats' owners to better meet cats' needs.
For example, owners could try to make climbing easier for cats by moving their furniture around. They could also use "food puzzles" to make eating feel more like hunting instead of just feeling
A. carved B. unknowingly C. ecosystem D. artificial E. elemental F. changing G. practically H. wrinkled I. unmoving J. species K. inspection |
Magical Creatures: AN APPRECIATION OF AUTUMN MOTH (蛾)
Moths seem to have a bit of a bad reputation: to some they are ill indications or something scary, to others they are dull in comparison to our well-loved butterflies. But moths are an essential part of a(n)
My first meeting with an Angle Shades moth was nearly a non-encounter. I almost passed by without noticing it, thinking it was a fallen leaf on a fence post. But there was something about it that stopped me in my tracks. Its angular shape perhaps? Or the way it sat,
The Canary-shouldered Thorn, with its hairy buttercup-coloured body and yellow and orange wings, reminds me of a fallen silver birch (白桦树) leaf. A night-flyer, it favours gardens and woodlands, and is often drawn to
There’s more to these imitators than fallen leaves. The Green-spotted Crescent, which
distance; remove; break away from; intend; eager; result in; surf; refer to; short; keep somebody company; recover; threat; stick |
The measures were effective. Up to now, the antelope population
A. advantageous B. programming C. fashion D. fueled AB. advanced AC. sacrifice AD. capped BC. habitually BD. appetite CD. likelihood ABC. unnecessarily |
Eating a calorie-rich diet brought us humans a great advantage: time. We spent less of the day obtaining food. We saved countless hours of needless chewing. Instead, we invested time in doing the things that make us human: we started to
Calories made humanity possible. Calories are what
Out there in nature, carrying extra body weight brings serious, even deadly, disadvantages. To the evolving primate, greater body mass means slower acceleration and a(n)
As we became more
All of these have left us with the following paradox: Why were humans generally able to resist vastly over-consuming calories up until about fifty years ago?
Quoted from Mark Schatzker’s The End of Craving
A. published B. weight C. obesity D. beginning E. less F. vulnerable G. admissions H. rise I. reduction J. Globally K. impacts |
The climate crisis is damaging the health of fetuses (胎儿), babies and infants across the world, six new studies have found.
Scientists discovered increased heat was linked to fast weight gain in babies, which increases the risk of
The studies,
“From the very
The link between heat and rapid
Hotter temperatures also increased the number of admissions of young children to emergency departments in New York City, another new study found. The scientists looked at 2.5m admissions over eight years and found that a 7℃
The burning of fossil fuels drives the climate crisis but also causes air pollution and a new study in Denmark assessed the impact of dirty air on 10,000 couples trying to conceive naturally. It found that increases in particle pollution of a few units during a menstrual cycle led to a decrease in conception of about 8%.
Wellenius said an important aspect of the studies was that they showed that
A. bind B. exact C. intently D. covers E. alert F. instantly G. remains H. springs I. attack J. identify K. triggered |
Antibodies play a key role in the immune system. They begin the process of getting rid of the invaders that may cause harm or infection. This lesson
What Are Antibodies?
Antibodies, also known as immunoglobulins, are Y-shaped proteins that are produced by the immune system to help stop intruders from harming the body. When an intruder enters the body, the immune system
Function
The antibodies act sort of like the immune system’s scouts. They find antigens, stick to them, and
How Antibodies Fight Antigens
So what happens when an antigen tries to enter the body? When it does, the immune system is
First, the virus is met by a type of cell called B cells. The B cells are responsible for creating antibodies to match the antigen. Remember, each type of antibody matches to only one antigen. After the B cells have created their antibodies, the antibodies stick to the virus, marking it for the next round of
After the antigen has been destroyed, the cleanup crew comes along. A wave of phagocytes large cells that can consume foreign matter, eats the
Immunizations
After an infection is defeated, the antibodies still remain in the body. They are left there to wait in case that particular antigen returns. Immunizations take advantage of the fact that antibodies remain in the body after an infection is eradicated. Most immunizations consist of a weak or diluted form of an antigen-not enough of the antigen to make the patient sick, but just enough to trigger the creation of antibodies. This way, the body can