Answer:
D. Warm front
Explanation:
Warm fronts typically have warmer and more moist air than the air in front of it. Replacing the cold air with warm air can cause precipitation.
Answer: Gene that arose through gene duplication, but by acquiring mutations became nonfunctional.
Explanation:
A gene is a functional unit of heredity formed by DNA. They possess a sequence of nitrogenous bases that during translation is read by ribosomes to produce molecules called proteins. A pseudogene is a DNA sequence that resembles a gene, but which has been inactivated in the course of evolution by mutations in its sequence. Thus, it is a gene that derives from other known genes and whose functions are different, <u>may have lost their functionality or have radically changed </u>it. To this day, it is not known exactly how pseudogenes are created, however some theories are as follows:
1. A gene duplication can generate two copies of a gene when only one is needed. A mutation would then occur that deactivates one of the copies. In addition, the duplication event may not be complete, so that the copy has incomplete promoters.
2. They may be fragments of the messenger RNA transcript of a gene may be spontaneously reverse transcribed and inserted into the chromosomal DNA. They lack the promoters of normal genes, so they are not expressed normally.
3. A gene may become non-functional or inactivated if such a mutation becomes fixed in the population. This can occur by normal means such as natural selection or genetic drift.
There are 8 planets in our solar system :)
Ok, a few things here:
This is an egg drop experiment, so I'm assuming you are testing out different ways of protecting the egg.
The independent variable is what you want to change: This would be the type of protection you have on the egg
The dependent variable is what would be effected by the changes in the independent variable: which would be something like the integrity of the egg after it hits the ground. You'd have to measure that somehow.
There are two types of controlled variables: <em>Internal and External.</em>
Internal variables are within the scope of the experiment and can be controlled, whereas external variables are outside the scope of the experiment and we have no control over them.
Internal:
- Height of the drop
- Type of egg
- Person dropping
- How the egg is dropped
- Surface being dropped on to
External:
- The person designated to drop the egg is sick
- You run out of eggs to drop
- Somebody loses all the planning for the experiment
- The weather forces you to do the experiment inside versus outside
- The wind blows your egg off course, leading to it hitting the ground at an angle
So, the way your teacher "chucks" the eggs off the roof should be a controlled internal variable. The action should be done as consistently as possible to avoid an uncontrolled variable.
<span>the lacrimal bone helps form the nasolacrimal canal necessary for tear translocation. A depression on the anterior inferior portion of the bone, the lacrimal fossa, houses the membranous lacrimal sac. Tears or lacrimal fluid, from the lacrimal glands, collect in this sac during excessive lacrimation. The fluid then flows through the nasolacrimal duct and into the nasopharynx. This drainage results in what is commonly referred to a runny nose during excessive crying or tear production. Injury or fracture of the lacrimal bone can result in posttraumatic obstruction of the lacrimal pathways</span>
