Why mosquito bites and it causes
itching?
A mosquito does not actually bite you, of course. It sucks
your blood.
To help enable effective blood sucking, it first injects
anti-coagulant saliva to stop the blood from clotting or forming a scab while it
feeds. When the mosquito goes away, its saliva stays in the pocket under your
skin.
Now comes the itchy part. Your body releases histamine to
fight off a foreign substance. It is the same as an allergic reaction. The
histamine causes swelling around the area and as a side effect, it itches.
What are the names and uses of the
various laboratory tools?
Tools include beakers, microscopes, tweezers, hot plates,
lasers, voltmeters, test tubes, Erlenmeyer flasks, thermometers, test tube
racks, Bunsen burners, crucibles, tripods and more. They are used to measure,
observe and gather data for experiments, as well as to perform reactions and to
heat things. More advanced laboratory equipment includes items such as
spectrometers, centrifuges and chromatographs.
Safety Tools
1. Eye Wash: In case materials get into your eyes, use this
to rinse them out
2. Safety Shower: In case materials get onto your clothing or
body, use this to rinse them off
How does caffeine effect plant
growth?
Minerals like potassium are often found alongside caffeine
when it occurs in plant sources like coffee beans, and that could help the plant
grow faster. However, the caffeine itself would be unlikely to have any affect
on the plant's rate of growth.
I tested it and the plant grew at normal rate but the leaves
were more wrinkly and browner
How do you determine if a molecule
is polar or non-polar?
A polar molecule is a molecule that has a net dipole moment
due to its having unsymmetrical polar bonds.
Two factors go into determining if a molecule is a polar. To
determine if a molecule (or ion) is polar or non-polar, you must determine both
factors.
1) The polarity of the individual bonds in the molecule;
2) The shape or geometry of the molecule
First, to determine if a given individual bond is a polar,
you need to know the electro negativity of two atoms involved in that bond. To
find the electro negativities of all the elements, look at the periodic table
(follow the link to the left of this answer under Web Links). If the electro
negativity of the two atoms has a difference of 0.3 or less, then the bond is
non-polar. If the electro negativity difference is greater that 0.3 but less
than 1.7, then the bond is polar.
Once you know which bonds in the molecule are known as polar
and which are non-polar, you must use the shape of the molecule. You need the
shape because two polar bonds, if oriented correctly can cancel each other out
(like two equally strong people pulling in opposite directions on a rope --
nobody moves). There are 3 possible outcomes:
What are the examples of
homeostasis?
Regulation of body temperature, control of blood glucose
levels, the regulation of salt and water balance
What is an analogy for a smooth
endoplasmic reticulum?
Endoplasmic reticulum (ER) is like a manufacturing plant,
like a factory, where proteins and lipids are made. This is also where things
are packaged into boxed and sent off to different places. In the cell the smooth
ER is a network of membrane bound bodies which lack ribosomes (the molecules
used in protein synthesis) and its primary function is to modify, encapsulate
and transport newly synthesized proteins and lipids which will be secreted or
remain in the cytoplasm as membrane bound vesicles. The smooth ER can also be
compared to a highway, or a protein and lipid highway, if you will. It is
sometimes called the transitional ER because it contains exit sites from which
transport vesicles carrying these proteins and lipids bud off for transport to
the Golgi apparatus. It is usually prominent in cells that specialize in lipid
metabolism and synthesis.
Does seed germination affect plant
growth?
Germination does affect plant growth
Without germination in the plant, the plant is not able to
grow. The germination is the beginning of life for the seed plant
However, the rate of germination is not directly related to
rates of plant growth one can find speedy germinating seeds, which grow slowly
and vice versa.
What is a recessive gene?
With the birth of a child, it gets its genes from both
parents. Some genes 'override' other genes. Using hair color as example:
If one parent is blond (Pb) and one parent is black hair
(Pd), blond would be the recessive gene, and dark would be the dominant gene.
Meaning:
Pb x Pb = Blond Pd x Pd = Dark
Pb x Pd = Dark Pd x Pb = Dark < /FONT > Recessive genes occur in the genotype (inside the body,
disease, disorder) or fenotype (appearance, blue eyes brown eyes). In all other
cases, the dominant gene will override the recessive gene.
What is cell biology?
Cell biology is the science of studying how cells function
such as their reproduction and metabolism, their internal and external anatomy.
What is the difference between an
acid and a base?
Base is any thing, which has a capability to abstract a
proton.
Using the simplest definition, an acid is something when
added to water releases hydrogen ions (H+), also called protons. A base, or an
alkali, is something that when added to water releases hydroxide (OH-) ions.
The strength of a basic (or alkaline) or acidic solution is
measured using the pH scale. A pH of 7 is perfectly pure neutral water (neither
acidic nor basic), and pH below 7 is acidic, and a pH above 7 is basic.
There is another definition, which says that an acid releases
H+ and a bases remove H+ from water. This definition is a bit more general than
the first one above. Note that releasing OH- is the same as removing H+. This is
because when OH- mixes with H+, they form neutral H2O, and so for every OH-
released, one H+ is removed by combining them into water.
The final definition of an acid and base is the most general,
but the hardest to understand conceptually, and it is not always taught in high
school because of this. According to this definition, acids are electron pair
acceptors, and bases are electron pair donors.
How much salt is in the human
body?
50 Kilo human has about 7 tablespoons of salt within him.
What is the optimum temperature
for catalyses?
For any chemical reaction, the reaction rate increases with
temperature, so the higher the temperature, the faster the rate. For any
enzymatic reaction, the reaction rate will increase with temperature until the
temperature at which the enzyme begins to denature is reached, and this is the
optimum temperature.
The denaturizing temperature depends on the composition of
the protein (its amino acid sequence), which varies for catalyses from different
organisms. Therefore, the answer to your question is that the optimum
temperature is dependent on the source organism.
What is a terrestrial organism?
'Terra' is the Latin word for earth. Therefore, an animal
that lives on the surface of the earth is called terrestrial. This is the same
root word as 'extraterrestrial' meaning an alien.
What are analogies for
mitochondria?
Well, as you know, the mitochondria are the producers of most
of a cell's energy and the nucleolus creates ribosomes. The cell wall is only in
a plant cell and is a rigid layer of non-living material that surrounds the
cells of plants and some organisms.
What happens when the cell
membrane or plasma membrane ruptures or breaks down?
When cell membrane ruptures Ions leek out and unless repaired
in time the cell will die. As we know that the plasma membrane is not
stationary, and it is made of lipids and protein, so when damage happens the
cell repairs itself by producing new part like the damaged one that is why it is
dynamic.
Which is better to grow plants in
Rock sand or soil?
When we grew plants inside, with no wind, and the plants in
the rocks grew better than the plants that were growing from the sand and dirt
from outside.
What are living and nonliving
reservoirs?
Viruses are both living as well as non-living. They have
reservoirs of genes. A single nucleotide is a unit of gene. Viral genes make use
of host raw material (non-living elements/organic moieties/ water etc.,)
including elements to synthesize organic molecules or macromolecules.
Subsequently, viruses replicate themselves thereby reproduce within the living
cells. On crystallization, they become non-living and can stay in this state for
years until they enter again into a living host to multiply. Certain plant
viruses are transmitted to the progeny through seeds. Viruses evolve as any
other living being. Therefore, now virus names are written in italics like
binomial/trinomial names similar to scientific name of any other living organism
i.e. Tobacco mosaic virus (read as italic).
All living entities on this earth (including viruses) are
part of Biosphere. Biosphere consists of genes that constitute the Genosphere.
Viral genes put together constitute Virosphere. Cancer is also caused by genes,
which lie within an organism. Certain cancers are caused by viruses and others
by genes, which reside in our body. These are called as virogenes or cancer
genes. These can be inherited to the offspring. Thus, living organisms
(Biosphere) are a reservoir of virogenes. No wonder there can be any life
without water. Life is only on this planet earth. To discovering life in
Universe, we first try to find water. Earth is a reservoir of living as well as
nonliving including water!
What is a characteristic feature
of a carrier protein in a plasma membrane?
Carrier proteins are globular proteins which are specific it
their action and thus regulate the entry and exit of particles into the cell.
They help in the conduction of ionic substances and polar substances.
What are some things that have
algae in them?
Yeast is considered Algae. The Research I have done says that
Dairy Products have Algae.
What is the natural habitat of
E.coli?
The E.coli was first identified in the colon region of large
intestine and so it was given the name "coli" (found in colon) they are
coliforms. It luxuriously grows in our large intestine and it is an important
normal microflora of human. It will not do any harm when present in intestine
and if it enters the blood or other sites of the body, it causes urinary tract
infection
How do keep respiratory system
healthy?
The circulatory system supplies food and oxygen to the body's
cell. It carries away waste production of energy. The wastes must then be
removed.
Who created the two-part naming
system used in biology?
The scientific naming system that is used worldwide today was
first devised by Swedish naturalist Carl Linnaeus in 1737. He proposed a
two-part naming system, which classifies every living organism with a string of
Latin and Greek identifiers. Full names are devised starting with kingdom and
extending downward through phylum, subphylum, class, order, family, genus and
species. The two-part name, or binomial name, consists of the genus and species
of the organism and used to prevent the confusion that may arise with common
names.
The binomial nomenclature (two-part name) of an organism
belongs to a universal format: the genus of the organism is the first name,
which is always capitalized, and acts as a noun. The species of the organism is
always the second name, is minuscule (lower-case), and acts as an adjective.
Take, for example, the cougar. The cougar's genus is Puma, and its species is
known as concolor. The entire name would read as follows, Puma concolor or P.
concolor for short.
What is an organ that belongs to
more than one organ system?
One answer is the pancreas. It belongs to both the endocrine
and digestive systems.
Another one is bone marrow. It is part of the skeletal and
the circulatory system because it makes both red and white blood cells.
Why do leaves change color?
Leaves are the food factories of plants. During the spring
and summer, leaves are actively making food and they are filled with
chlorophyll, which gives green color. As summer, ends and the days get shorter
and cooler, food production stops and the leaves stop producing food. The
chlorophyll disappears and they begin to change into the yellows, oranges, and
reds that we see in autumn.
Why would a tongue not detect mild
sweetness after eating foods with high sweetness?
This happens because of the "desensitization" of sensory
receptors on the sensory cells of your tongue. This phenomenon occurs in all of
our senses, where a strong and continuous stimulus desensitizes us to the same
stimulus, so that it is harder to detect. For example, this is how you adjust to
new smells, or why it is harder to hear after attending a loud concert. It is
part of how your body is able to adapt to new environments. The sensory cells of
your sensory organs regulate and “desensitize” these receptors in multiple ways.
For instance, sensory receptors on the cell surface can be deactivated or cells
can internalize the receptors and degrade them, both of these events effectively
reduce the number of functioning receptors on the cell surface and thus reduce
its ability to detect a stimulus.
Why do preserved foods not spoil?
Plant and animal cells must stay in an isotonic, or neutral,
solution to survive. When salt or sugar is added, many of the cells wither and
die, and the bacteria cannot live on dead cells.
Sometimes they have agents added that do not allow bacteria
and other microbes to colonize and grow on the food. Microbes like bacteria and
fungus break down the food causing the spoilage.
There are bacteria and other microorganisms, which live in
all sorts of environments. Some tolerate oxygen and some do not. Some tolerate
salt and some do not.
There are certain limits or parameters outside of which most
or no microorganisms can remain active, however this is theoretical. There have
been microorganisms such as Archea living in thermal vents, hot springs, salt
lakes, and other extreme environments for ages and ages.
Some microorganisms create "spores" which are like hard
seeds, which can survive for many years under harsh conditions, waiting until
conditions are right to germinate and become active again. One example of this
is Bacillus Anthracis, the bacteria that causes Anthrax.
What is an analogy for
microtubules?
Microtubules have two main functions in cells and in doing so
act like a skeleton as well as like railroad tracks. Microtubules are the main
structural component of the cytoskeleton in cells, which provides the cell with
structure and rigidity and determines the shape of the cell. They also serve to
transport vesicles and proteins within the cytoplasm through transport proteins
called kinesins and dyneins, which act much like railroad cars.
What is the tallness trait of a
pea plant moving separately from the color trait an example of?
This is an example of Mendel's second law, the Law of
Independent Assortment, which states that the appearance of one trait will not
affect the appearance of another. Current understanding of genetic inheritance,
however, has shown that this is not always the case because two genes, which are
located close to each other on the same chromosome, will most likely be
inherited together.
What are two things that enter the
cell for cellular respiration?
Carbohydrate molecules and oxygen enter the cell during
cellular respiration.
How does the structure of a crab
relate to its habitat?
Its hard exoskeleton protects it for most predators &
keeps water off its flesh. The claws are used for mating duels & protection.
The reason for so many legs is for grip on and off land.
What are blood enzymes?
Enzymes are proteins that carry out chemical reactions (as
opposed to structural enzymes). Most of the detectable enzymes in the blood come
from the various tissues and organs of the body. Abnormal levels may reflect
problems with a particular organ.
The most common blood enzymes test is for liver enzymes. When
the cells of the liver are damaged, enzymes can leak out and detected in the
blood. Another common test measures enzymes from heart damage, such as from a
heart attack.
How do organisms adjust to changes
in temperature?
Some of the most common way for an organism to adjust to
changes in body temperature is through perspiration or panting. As previously
mentioned, this is all part of the balance mechanism known as homeostasis, which
is usually defined as the "maintenance of a relatively stable, internal
environment."
What does an anther have on it?
The anther is the part of the flower that holds the pollen.
This and the filament both make up the stamen.
Do all vascular plants develop
annual rings?
Vascular plants are those, which have phloem and xylem
structures within them to transport water and nutrients around the plant. Most
of the plants you see around you are vascular. Think about grass or herbaceous
plants - you will not find growth rings in those if you cut them through the
middle.
Growth rings occur is plants with lignin in their stems
(trees in other words). The rings are caused by the different rates of growth in
summer and winter. In summer the tree grows quicker, the lignin fibers are less
dense, and the ring is a bit lighter in color. In winter, growth is slower and
the fibers are pack closer and appear darker.
Annual growth rings are near universal in the trees of the
temperate regions. Trees growing in the tropics experience an even temperature
environment over the year and rings are less pronounced or absent.
How does the odor of flower petals
help pollination?
The purpose of the perfume is to attract a pollinator -
insect, bat, bird or whatever. The reward for the pollinator is a meal of
nectar, which is produced by the flower.
Why does DNA twist?
If it did not twist, would you expect it to fit into the
miniscule cell? As we all know, if we join all of the DNA molecules from a
person's body end to end, we would get length three times the distance from the
centre of the earth to the sun! Therefore, DNA does not have a choice but to
follow the super solenoid structure. This is also aided by the purine-pyrimidine
linkages, to balance the weight of DNA components. Why pressing down on the
cover slip does not remove excess water. Because of Newton's Third Law of
Motion: Every action has an equal an opposite reaction and hydraulic pressure.
When you press down on the cover slip, the water underneath it pushes back
against you with the same force that you are pressing down on it. If you want to
get the water to move out from under the cover slip, you need to direct it to
the side. One way to do this is to lift an edge and break the suction, then set
it back down on one edge first to let the water run out, then press it down.
This creates a side motion so the water does not push straight up into the cover
slip, but pushes at an angle, which allows it to run out.
The same principle applies to squeezing an egg. If you
squeeze an egg in your hand with even pressure all the way around, it will not
crack because the eggshell presses back into your hand with the same pressure.
The pressure is so evenly distributed around the egg that it resists breaking.
However, if you hold it with more pressure going into it from a side angle, like
only squeezing a part of the egg, then it will break. That is the same idea as
the cover slip; if you use an angle from the side, the force pushing back at you
that does not have support so it allows the water to leak out.
What are some examples of chemical
and physical changes?
Chemical changes are irreversible changes such as combustion
and frying an egg.
Physical changes are reversible changes such as ice melting
and deflating a ball.
What is the importance of
genetics?
It also improves the human race is some cases such as the
lately people being born without appendix.
Hitler kind had the idea of genetics in mind when he created
his 'master race' of blue-eyed blonde hair people. As a result, today blue eyes
are getting rarer and rarer as the green/brown eye gene takes over.
1 in 100,000 people on average have a mutation. Mutations are
what cause evolution. If for example a baby were born with, a natural immunity
to AIDS then that would be a beneficial mutation to human race. If that child
grew up and had many children then eventually the gene would spread and one day
all people would be immune to aids.
What is the movement of
paramiciumcillia?
Paramecium: This large single-celled protist contains many,
many short little "hair-like" structures called cillia that cover the entire
cell. The cillia move like little oars that help the paramecium swim and gather
food into its "food grove". The paramecium appears a light pink in color. It is
known as a Ciliate.
What are analogies for centrioles?
A Centriole is like a straw because they both are tubes that
let things get from one end to the other end.
The centriole has a round look to it because it is made from
nine triplets of microtubules that make a straw-like (as said above) look.
Why do organisms live in certain
places?
Think of that, the temperature difference in the desert is
huge. So in order to survive, the cactus plant reduces heat gain and heat loss
as well as water loss. (E.g. narrow pin shaped leaves, long extensive roots)
Why do substances react with each
other?
Chemical reactions occur because the products of the reaction
have less energy than the reactants (drive toward less energy). These reactions
release energy into the environment, like the burning of a match. Chemical
reactions also occur because the products are more random (less ordered) than
the reactant (drive toward greater entropy).
What are the uses of formycin B?
Formycin B is a drug used to destroy of intestinal parasites.
How does iodine kill germs?
The microbiocidal action of Iodine is due to the active form,
I2, which is polarized by water and like all halogens (chlorine, fluorine,
bromine, etc.), acts as an extremely potent oxidizer. Activated iodine (I2)
reacts in electrophilic reactions with enzymes of the respiratory chain as well
as with amino acids located in cell membrane and cell wall proteins. The
well-balanced tertiary structure necessary for maintaining the respiratory chain
as well as cell integrity is destroyed and the microorganism is irreversibly
damaged.
What are the complementary
base-pairing rules for biology?
In DNA, Adenine bonds with Thymine, Cytosine bonds with
Guanine. In RNA, Thymine is replaced with Uracil (bases capitalized for easy
emphasis/reference, not grammar.)
Purines and Pyrimidines are two families of Nitrogenous
bases.
In DNA:
Adenine and Guanine: Purines
Cytosine and Thymine: Pyrimidines
Adenine bonds with Thymine and Guanine bonds with Cytosine.
A&T have 2 hydrogen bonds and G&C have 3 hydrogen
bonds.
What is the difference between
xylem and phloem?
Both xylem and phloem are vascular tissues found in a plant.
Xylem is a tubular structure, which is responsible for water transport from the
roots towards all of the parts of the plant. Phloem is also a tubular structure,
which, on the other hand, is responsible for the transportation of food and
other nutrients needed by plant.
Why is water conservation in c3 c4
and cam plants important?
Cam stands for Crassulacean acid metabolism.
C3 and C4 conserve less water than Cam plants.
Actually, C4 plant captures more carbon than C3 plant. In the
struggle to reduce carbon dioxide concentration in the atmosphere, genetic
scientists have modified some large-scale crops into C4 bases. Cam plant is
wholly different from C3 and C4 and examples of are the cactus and other
succulent plants in order to survive in dry dusty regions. In Cam plants, carbon
fixation occurs at night while C3 and C4 plants carry out photosynthesis during
daylights.
What does veterinary medicine have
to do with physiology and biochemistry?
A lot of Physiology will teach about the function of animals
and their parts. This is very important, so you know about the animals you take
care of and about parts affected by certain illnesses and injury. Biochemistry
is the chemical processes of living things- digestion, defecation, blood, etc.
What is the main difference
between a bird heart and a mammalian heart?
The bird heart has a single aortic arch on the right side of
its body while the mammalian heart has one on the left.
What are the lowest and highest
temperatures humans can survive?
Being in cold temperature air with proper shelter and
clothing, humans can survive indefinitely, even if the temperature is below zero
degrees. However, a person in regular clothing immersed in water just above
freezing will last only a few minutes.
As for heat: A sauna can reach temperatures of close to 200
degrees, but since the air is around 10% humidity, it actually feels comfortable
and has many healing properties. However, if the air is 90% humidity, then the
safe temperature is more like around 110 degrees.
So maybe a better question to ask is at what
temperature and humidity combinations are humans capable of surviving?
What has caused evolution?
1) Different individuals have different characteristics
2) these differences result in varying abilities to reproduce
under local circumstances
3) Some of these differences are inherited
4) Those inherited differences that result in highly
successful reproduction rates are the ones that will be present at higher
percentages in the new generation.
Evolution is common sense but they have very close common
ancestors. Now, think about evolution on a family, tribe, society level. Some
individuals preserve there species line by being protectors or servants. (ex:
ants, bees, certain species of birds) further ex: if a son helps raise 20 of his
siblings but does not reproduce himself, then, the DNA from his parents will
still be transferred in great abundance even if he doesn’t reproduce at all.
Sometimes behavioral evolution is harder to explain in only simple definitions.
Think about it.
What are organelles, which carry
out autophagy?
Autophagy, being the degradation of cytoplasmic components as
well as other organelles, is generally done with the lysosomes. The lysosomes,
contain enzymes (hydrolase and others) to digest these worn out, damaged, or
infected parts, which keeps the cell healthy and clean. mTOR regulates this
process (mammalian target of rapamycin). Lysosomes do carry out a similar
procedure to autophagy. It is called autolysis, and that is when the lysosome,
excretes all of its digestive juices into the cell. It is like a self-destruct
and the entire cell is condemned to a digestive end. Do not worry it only
applies to damaged cells.
What best describes the amoebas
division?
(1) It is a Mode of asexual account in which a single parent
is involved. The amoeba cell, which is unicellular, divides into two daughter
cells, which are identical. First, the nucleus divides, then the cytoplasm and
then plasma membranes.
(2) Sporulation when the environmental conditions are
unfavorable, the amoeba cell secrets a 3 forming a cyst. This is called
encystations. When are favorable the cell divides by multiple fission and form
small pseudopodiospores the like totally wall breaks all the houses
pseudopodiospores are released.
Are there ribosomes in a plant
cell?
Yes, in fact there are ribosomes in both plant and animal
cells.
That is right. Ribosomes are the site of synthesis of
polypeptide chains; proteins are formed from polypeptide chains. Both animals
and plants need proteins for many purposes, not least as enzymes.
There are also ribosomes in prokaryotic cells, but these are
smaller. The ribosomes in prokaryotes have a sedimentation rate of 70S (Svedberg
units); eukaryotes have 80S ribosomes.
They are the sites of protein synthesis, which makes them as
important as other cell organelles.
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