Observation is broken up into three parts. The first is the date. Then you have the activity and last you have a brief description of what is being observed.
The web page (below) provides: Mesozoic ("Middle Life") Era
This is the second of three geologic eras squeezed into the Phanerozoic ("Evident Life") Eon that covers the last 10% of Earth's whole geologic history. This is the era we all think of when we imagine the Ancient Earth! Rampaging dinosaurs! Dive-bombing pterodactyls! Endless forests of giant ferns! Erupting Volcanoes! (Sorry, no cave men! They didn't show up until the end of the Cenozoic.)
The Mesozoic Era lasted about 180 million years, from about 245 million years ago to about 65 million years ago. The Mesozoic is divided into just three time periods: the Triassic, the Jurassic, and the Cretaceous. Since lots of things were going on in each time period, we can only summarize the events. You can learn more by going to your library or searching the Internet for words like "Mesozoic" or the names of each of the periods.
In the view above, we see Earth in the middle of the Jurassic Period, in mid-Mesozoic times (sort of a middle-middle view). The supercontinents Gondwanaland and Laurasia collided some time back to form a single super-super continent called Pangea ("All-Earth"). But plate tectonics continues its irresistible motions, and even as we look, Pangea is beginning to break up into the continents we know now. At upper left, North America is just breaking away from the northwest coast of Africa, and the Atlantic Ocean and Gulf of Mexico are beginning to form. The Appalachian Mountains of the eastern United States are a high, rugged mountain range, something like the Rocky Mountains of today. Over the next fifty million years or so, South America, India, and Antarctica will all break away from Africa and move toward their present positions.
Life is diversifying rapidly, and beginning to look familiar. The dominant animals on both land and sea are reptiles, the most famous of which are the dinosaurs. Dinosaurs began in the Triassic, spread during the Jurassic, and dominated Earth in the Cretaceous. They are so prominent that the Mesozoic is also called "The Age of Reptiles." But dinosaurs are not the only life form around: birds and mammals also appear during the Mesozoic, as well as deciduous trees and flowering plants.
The climate during the Mesozoic is warm; so warm that there are no ice caps at all, even at the poles! Plants grow like crazy in the warmth and moisture, so there is food everywhere for your average hungry 50-ton Ultrasaurus! So what happened to this Dino Paradise? More change! A mass extinction like those in the Paleozoic ended the idyllic Mesozoic Era (if you can call dodging your friendly local T-Rex as idyllic). More than half of all existing life forms disappeared, including virtually all of the dinosaurs. Why? There are many hypotheses, including disease, volcanic eruptions, and giant impacts. (Pay a visit to the Dinosaur Floor to learn more.
seems based on text above, most correct is "A" definitely not "C"
BioSafety Level (BSL) 3 labs,
perform work with indigenous or exotic agents that may cause serious or
potentially lethal diseases through the inhalation exposure. Biological Safety
Levels (BSL) are a sets of protections assigned to the activities that occur in
specific biological laboratories. BSL protects laboratory workers, the
surrounding environment and also the community.
Answer:
There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus.
<u>Gravity</u>: A good example of gravity dispersal is the marigold flower. When they are ready, these seeds drop to the ground.
<u>Wind</u>: There are two types of wind dispersal adaptations, the floaters, and the fliers:
<u>(wind) Floaters</u>: The common dandelion is a good example of this type of seed dispersal.
<u>(wind) Fliers</u>: Maple seeds grow in pairs, but when they are mature, they separate, and a strong wind can pull them from the stem
<u>Ballistic</u>: Some common examples of this type of dispersal are garden peas. When the cells grow older, the result is that the pods break open and twist. This twisting actions pops the seeds lose and pushes them away from the pod.
<u>Water</u>: Coconuts have a husk that surrounds the seed. This husk is very buoyant and a coconut seed can float across hundreds of miles of ocean before washing ashore on a new island to germinate and grow into a tree.
<u>Animals</u>: there are also two types of these, hitchhikers and edibles. Seeds that stick to the outside of animals, or are spread when they go out the other end after being eaten:
<u>Hitchhikers</u>: Some examples are cockleburs and foxtail.
<u>Edibles</u>: These seeds are surrounded by good tasting fruit, like apples and peaches.
