Answer:
Condyle
Explanation:
The condyle is one of the outgrowth or projections present at the surface of the bone. The condyle is large and round in shape. It has a smooth articular surface and serves in joints formation. The condyle is present at the end of one bone and joins it with other bones.
Example: occipital condyles of occipital bone serve in joint formation with the first vertebra of the vertebral column.
A small, rounded depression on a bone that is meant for articulation is called a fossa. It is a hollow or depression that helps connect other structures like muscles or other bones.
Explanation:In the field of biology, specifically in the study of human or animal anatomy, a small, rounded depression on a bone that is meant for articulation is called a(n) fossa. This is a specific type of bone landmark, where other structures, such as muscles, tendons, or other bones, would connect. To help remember this, think of a 'fossa' as a hollow or depression in a bone that helps to form a joint. It's different from a trochanter, which is a large, rough projection, a tuberosity, which is a moderate protuberance where muscles and connective tissues attach, a condyle, that is a smooth, rounded articulating area, and a foramen, which is a hole that allows passage of nerves and or vessels.
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which type of biome is the least productive
Hello There!
The "TUNDRA" biome is the least productive biome there is.
The tundra biome is known for its frost-molded landscapes, very low temperatures and little precipitation.
There are two types of the tundra biome. These are called the alpine tundra and the polar/arctic tundra.
Answer:
tundra
Explanation:
apex
Mendel crossed peas having round seeds and yellow cotyledons (seed leaves) with peas having wrinkled seeds and green cotyledons. All the F1 plants had round seeds with yellow cotyledons. Diagram this cross through the F2 generation, using both the Punnett square and forked-line, or branch diagram, methods.
Answer:
Let:
Y = Yellow R = Round
y = green r = Wrinkled
If you look at the F1 generation, all the plants are round and yellow, so these are the dominant traits and each offspring is heterozygous for both traits. The cross for the F2 generation would then be:
YyRr x YyRr
In a Punnett it would look like the attached picture.
For the forked-line diagram, first you will need to know the gentypes and ratio of each trait in a monohybrid cross. Select one trait, and then branch each gentype to the next trait, linking it with each possible genotype combination of the monohybrid cross.
Attached is a picture of the Forked Branch diagram for this cross.
Mendel crossed pea plants with different traits and observed the inheritance patterns in the F2 generation. The Punnett square and forked-line methods can be used to diagram this cross. The F2 generation showed a ratio of 9/16 round yellow seeds, 3/16 wrinkled yellow seeds, 3/16 round green seeds, and 1/16 wrinkled green seeds.
Explanation:Mendel crossed peas with round seeds and yellow cotyledons (seed leaves) with peas having wrinkled seeds and green cotyledons. In the F1 generation, all the plants had round seeds with yellow cotyledons. To diagram this cross through the F2 generation, we can use both the Punnett square and forked-line methods. Using the Punnett square, we can see that in the F2 generation, there is a 9/16 probability of getting round yellow seeds, 3/16 probability of wrinkled yellow seeds, 3/16 probability of round green seeds, and 1/16 probability of wrinkled green seeds. This demonstrates independent assortment of the two traits.
which type of molecule prevents cell membranes from dissolving in water?
a. Nonpolar fatty acids
b. Large globular proteins
c. Polar nucleotides
d. Complex carbohydrates
Answer:
d. Complex carbohydrates
Explanation:
Complex carbohydrates prevents cell membranes from dissolving in water.
Answer:
The answer is a. Nonpolar fatty acids
Explanation:
The answer is a. Nonpolar fatty acids
What makes a cell membrane insoluble in water is that it contains a hydrophobic end. This hydrophobic end normally consists of two fatty acid chains nonpolar molecules, which are carbons and hydrogens. Fatty acids can be saturated or unsaturated.
What hormones need to be released in order to signal the thyroid gland to secrete thyroid hormone? Select all that apply.
a. TRH
b. TSH
c. ACTH
d. CRH
Answer:
Thyroid Stimulating Hormone (TSH)
Explanation:
TSH also called thyrotropin is released by the anterior pituitary gland and stimulates the thyroid glands to secrete the thyroid hormones throxine, triiodothyronine and tetraiodothyronine. Release of TSH is due to the stimulation of the anterior pituitary gland by the hypothalamus through the hormone Thyroid Releasing Hormone (TSH). Adrenocorticotropin hormone (ACTH) is released by the anterior pituitary gland due to hypothalamic stimulation through the hormone Corticotropin Hormone (CRH) that helps in synthesis and release of ACTH.
What are the functions of hydrochloric acid in the stomach?
Final answer:
Hydrochloric acid in the stomach functions to create an acidic environment necessary for killing bacteria and enabling the digestion of proteins by activating the enzyme pepsin and denaturing proteins for efficient breakdown.
Explanation:
Hydrochloric acid (HCl) in the stomach serves several important functions in the digestive process. The stomach produces HCl as part of the gastric juice, and its functions include:
Activation of Pepsinogen: HCl activates the enzyme pepsinogen, converting it into pepsin. Pepsin is crucial for breaking down proteins into smaller peptides and amino acids. This initial protein digestion is a fundamental step in the overall digestion process.Optimization of Enzyme Activity: HCl helps create an acidic environment that optimizes the activity of digestive enzymes. While pepsin works on proteins, the acidic pH also facilitates the activity of other enzymes, such as gastric lipase, which begins the digestion of fats.Sterilization of the Stomach Contents: The acidic environment created by HCl helps to sterilize the stomach contents by killing many bacteria and other microorganisms that may be ingested with food. This is part of the body's defense mechanism against potentially harmful pathogens.Denaturation of Proteins: HCl assists in the denaturation of ingested proteins, unfolding their three-dimensional structures. This process makes it easier for enzymes like pepsin to access and break down the peptide bonds within the proteins.Activation of Intrinsic Factor: Intrinsic factor, a glycoprotein produced in the stomach, is necessary for the absorption of vitamin B12 in the small intestine. HCl plays a role in releasing vitamin B12 from food, allowing it to bind with intrinsic factors for absorption later in the digestive tract.The acidic environment created by hydrochloric acid is critical for the overall efficiency of the digestive process. It prepares ingested food for further digestion and absorption in the small intestine, ensuring that nutrients are properly broken down and made available for absorption into the bloodstream.
What are the correct steps in the transformation of a sedimentary rock into a metamorphic rock? rock eroded away and deposited in alluvial fan ® rock buried deeply and melted by intrusion rock eroded away and deposited in ocean basin ® volcano erupts through ocean floor and melts rocks rock eroded away and deposited in ocean basin ® rock buried under many layers of sediments rock eroded away and deposited in ocean basin ® rock pulled into subduction zone and melted
Answer:
hey...im not sure about the answer but i think it is the 2nd option which is: rocks buried deeply and melted by intrusion rock erodedaway and deposited in ocea n base
hope it helps
Metamorphic rocks are produced when rocks are affected to high pressures, high temperatures, hot mineral-rich fluids, or, more usually, any accumulation of these possessions. Thus, option B is correct.
What results in sedimentary rock into a metamorphic rock?If subjected to sufficient heat and pressure, sedimentary rocks like bituminous coal, limestone, and sandstone can undergo nonfoliated metamorphic rock formation, giving rise to anthracite coal, marble, and quartzite.
These kinds of conditions can be found deep inside the Earth or where tectonic plates collide.
Metamorphism, which occurs when magma interacts with the surrounding rock, is another process that can produce nonfoliated rocks.
Therefore, deep-buried rock that has been melted by incursion rock was lost to erosion and dumped in the ocean basin.
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An influx of sodium into the resting cell would lead to this.
Answer:
The influx of sodium ions causes the depolarization in the resting cells.
Explanation:
Resting cells has the membrane potential of -70 mV. Potassium ions are abundant in the resting cell.
The influx of sodium ions in the resting cells will increase the membrane potential from -70mV to 30mV. The cells will depolarize die to the influx of sodium ions and the cell inside environment will become more positive than outside environment of the cell.
Thus, the cells will depolarize by the influx of sodium ions.
Predict what would happen if Griffith had mixed some heat-killed type IIIS (virulent) bacteria and some heat-killed type IIR (non-virulent) bacteria and injected these into a mouse.
A. The mouse would have contracted pneumonia and died because the type IIIS would have been transformed by the type IIR bacteria.
B. The mouse would have contracted pneumonia and died because the type IIR would have been transformed by the type IIIS bacteria.
C. The mouse would have lived because the type IIIS bacteria are not pathogenic.
D. The mouse would have lived because the type IIR bacteria are not pathogenic.
E. The mouse would have lived because only living bacteria can be transformed.
The mouse in the scenario would survive. This result comes from Griffith's experiments showing that transformation, where a strain of bacteria changes by contact with another strain's DNA, requires living bacteria. Since both types of bacteria are heat-killed, they can't cause pneumonia or become transformed.
Explanation:In the scenario proposed, where Griffith mixed some heat-killed type IIIS (virulent) bacteria and some heat-killed type IIR (non-virulent) bacteria and injected these into a mouse, the mouse would have survived. This conclusion comes from Griffith's transformation principle experiments.
This effect occurs because transformation, or the process of one strain of bacteria changing due to being in contact with another strain's DNA, requires living bacteria. Since both types of bacteria, IIIS and IIR, are heat-killed, they are not alive and thus not capable of being transformed or causing pneumonia.
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With the exception of identical twins, it is said that no two people are just alike. But is this true? Is it virtually impossible for people other than identical twins to have exactly the same DNA and be identical to each other? WHY or WHY NOT?
Answer:
yes
Explanation:
As they can be the family of the same father and mother
A muscle of mastication
a. Masseter
b.Temporalis
Answer:
A.Masseter
Explanation:
allow me to explain,Those are the four muscles of mastication. You've got the temporalis, the masseter (which is this muscle here) and you've got the medial and lateral pterygoid muscles. The medial pterygoid muscles are involved in elevation and side to side movements of the mandible.
A number of different types of mutations in the HBB gene can cause human β-thalassemia, a disease characterized by various levels of anemia. Many of these mutations occur within introns or in upstream noncoding sequences. Explain why mutations in these regions often lead to severe disease, although they may not directly alter the coding regions of the gene.
Answer:
Mutations in introns create alternative splicing site which in turn make mRNA with reduced or no translation.
Explanation:
Introns regulate the splicing of heterogenous RNA during post transcriptional modifications as well as affect the stability of mature mRNA. The stable mRNA is more likely to be translated into proteins. So, introns also regulate the translation of mRNA.
In human beta thalassemia, mutations in intron create alternative splicing sites which in turn affect the formation of beta globin chain of hemoglobin. Lack of beta globin chain reduces the amount of functional hemoglobin and causes anemia.
On which bone does Styloid Process occurs?
Answer:
the styloid process is located rt.above or superior to the sternum.
of the chest, between the rib cage.
Explanation:
it is actually located rt. above the sternum.
The first line of defense against pathogens includes:
A. Inflammation and phagocytosis
B. The skin and mucous membranes
C. Interferon and complement
D. Fever and lysozyme
E. Skin and phagocytosis
Answer: Option B
Explanation: The first line of defense acts a barrier and does not allows the foreign materials to enter inside the body. It includes chemical and physical barriers that are always ready to protect the body from infection.
Example: Skin and mucous membrane.
Skin is largest organ and it acts as a barrier between pathogens and human body. It acts a waterproof material and the pathogens cannot get inside through skin unless the skin is broken.
Mucous membranes also acts as first line of defense and breaks the cell wall of many bacteria entering through the openings of the body.
So, skin and mucous membrane are the first line of defense.
____ patterns occur all around us in nature.
Hello There!
"Natural" patterns occur all around us in nature.
If a volcano were to erupt and release large amounts of ash into the air, how would this affect the climate on Earth? A. The ash would increase the albedo and decrease the global temperature. B. The ash would decrease the albedo and increase the global temperature. C. The ash would increase the greenhouse gases, thus increasing temperature. D. The ash would decrease the greenhouse gases, thus decreasing temperature.
Answer:
A. The ash would increase the albedo and decrease the global temperature
Explanation:
The volcanoes can have a big impact on the global temperature. If the volcanic eruption is big enough, and the volcanoes manages to propel very large amount of ash in the atmosphere, the whole planet will feel the effect. The ash will make a layer in the atmosphere around the planet. This layer will increase the albedo of the atmosphere, as the ash will block big portion of the sunlight. That will result in much less sunlight reaching the surface of the Earth, thus in sharp decrease in the global temperatures.
25 points question!!!!
What is the state of Michigan doing to fix the problem of purple loosestrifes? (invasive species)
I need a source( from where did you get the answer)
The purple loosestirfes are a beautiful wild plant. They are native of Eurasia, more specifically Macedonia, and they have been brought by accident in North America. Once there, this plant managed to spread out very quickly in the wetlands, rapidly overtaking the territory of the native species. The problem became very serious, especially in Michigan, so the scientists from the universities started to make projects in order to stop this invasive species from destroying the local flora and even fauna. The biggest steps made have been by releasing natural enemies of this plant where it has spread out. The natural enemies are all insects, and they have selectively been released to be only harmful tot he purple loosestrife, but not the other plants. The effects have been good, as the insects managed to reduce the density of this invasive species by a lot, opening up space for the native species to thrive again.
Source: Michigan State University
In an electrophoretic study of enzyme variation in a species of pelican, you find 77 A1A1, 45 A1A2, and 18 A2A2 individuals at a particular locus in a sample of 140. What are the allele frequencies for the A1 and A2 alleles? Calculate the genotype frequencies for this locus.
Answer:
Frequencies of allele [tex]A_{1}[/tex] and [tex]A_{2}\\[/tex] are [tex]0.74[/tex] and [tex]0.26[/tex] respectively.
Frequencies of Individuals with genotype [tex]A_{1}A_{1}, [tex]A_{2}A_{2} and [tex]A_{1}A_{2} are [tex]0.55, 0.128, 0.32[/tex] respectively.
Explanation:
As per Hardy Weinberg's equation -
[tex]p^{2} +q^{2} +2pq= 1[/tex] ----------Equation (A)
[tex]p+q= 1[/tex]-----------Equation (B)
Where "p" represents the frequency of "[tex]A_{1}[/tex]
"q" represents the frequency of "[tex]A_{2}[/tex]
[tex]p^{2}[/tex] represents frequency of individual [tex]A_{1}A_{1}[/tex]
[tex]q^{2}[/tex] represents frequency of individual [tex]A_{2}A_{2}[/tex]
[tex]pq[/tex] represents frequency of individual [tex]A_{1}A_{2}[/tex]
Here genotype frequencies are -
[tex]A_{1}A_{1} = 77\\p^{2} = \frac{77}{140} \\= 0.55\\[/tex]
[tex]A_{2}A_{2} = 18\\q^{2} = \frac{18}{140} \\= 0.128\\[/tex]
Substituting this values in equation A, we get
[tex]0.55 + 0.128 + 2pq = 1\\2pq = 1-(0.128+ 0.55)pq = 0.321[/tex]
Frequencies of allele [tex]A_{1}[/tex] and [tex]A_{2}\\[/tex] are -
For [tex]A_{1}[/tex][tex]= \sqrt{p^{2} } \\= \sqrt{0.55} \\= 0.74[/tex]
Substituting this value in equation B, we get
[tex]p+q=1\\0.74 + q = 1\\q = 1-0.74\\q = 0.26[/tex]
Frequencies of allele [tex]A_{1}[/tex] and [tex]A_{2}\\[/tex] are [tex]0.74[/tex] and [tex]0.26[/tex] respectively.
Frequencies of Individuals with genotype [tex]A_{1}A_{1}, A_{2}A_{2}, A_{1}A_{2}[/tex]are [tex]0.55, 0.128, 0.32[/tex] respectively.
A cell bearing CD8 on its surface would be most similar to or have the most in common with which of the following cells?
Question 8 options:
follicular dendritic cells
NK cells
monocytes
macrophages
dendritic cells
Answer:
Option). NK cells.
Explanation:
Cluster of differentiation 8 (CD8) can bed defined as a transmembrane glycoprotein that acts a co-receptor for the receptor present on T cells (TCR). The CD8 is marker for [tex]T_c[/tex] cells (cytotoxic T cells) as it is predominantly present on cell surface of these cells.
Along with cytotoxic cells, CD8 molecule is also expressed in surface of natural killer cells (NK cells), thymocytes, and myeloid dendritic cells.
Hence, a cell having CD8 on its surface (cytotoxic T cell) would be most similar to NK cells.
The correct answer is c. monocytes.
CD8, also known as cluster of differentiation 8, is a protein found on the surface of certain cells of the immune system. Specifically, CD8 is expressed on the surface of cytotoxic T cells, which are a type of lymphocyte that plays a crucial role in the immune response. These cells are capable of directly killing infected cells, particularly those infected with viruses or transformed by cancer.
Monocytes are a type of white blood cell that circulate in the blood and can differentiate into macrophages and dendritic cells once they migrate into tissues. Monocytes express CD8 at a lower level compared to the high levels found on cytotoxic T cells, but they are still part of the immune system's response to infection and are involved in phagocytosis and antigen presentation.
Let's consider the other options:
a. Follicular dendritic cells: These cells are found in lymphoid follicles and are involved in the humoral immune response by presenting antigens to B cells. They do not express CD8.
b. NK cells (Natural Killer cells): These cells are part of the innate immune system and can kill infected or cancerous cells without prior sensitization. While they share some functions with CD8+ T cells, they do not express CD8.
d. Dendritic cells: These are antigen-presenting cells that process antigen material and present it on the surface to other cells of the immune system. They can express CD8, but not typically at the levels seen on cytotoxic T cells.
e. Macrophages: These are specialized cells involved in the detection, phagocytosis, and destruction of bacteria and other harmful organisms. While they can be derived from monocytes, they do not typically express CD8.
Therefore, monocytes are the cells that would be most similar to or have the most in common with a cell bearing CD8 on its surface, as they can express CD8 and are part of the immune system's response.
Mr. Brown's blood typing results showed no agglutination when his blood sample was mixed with either plasma containing anti -A or anti - B antibodies. What is his blood type and what blood type can he receive?
Answer:
Mr Brown's blood type: AB
He can receive blood from: A, B, AB and O blood type (universal recipient)
Explanation:
Mr. Brown's blood does not exhibit agglutination with both plasma having anti -A or anti - B antibodies. The anti -A antibodies and B antigen are present in B blood type while A blood type has anti - B antibodies and A antigen.
Mr. Brown's blood does not show agglutination for both A and B antigens which means that his blood lack both anti -A or anti - B antibodies. The blood type that lacks both anti -A or anti - B antibodies is "AB" blood type. So, Mr. Brown's blood type is the "AB" blood type.
Since his blood lack both antibodies, he can receive blood from all blood types, that is, A, B, AB, and O.
How does the sheep brain compare to the human brain? Identify at least two differences.
Answer:
Sheep Brain:
Sheep brain is smaller in size the human brain. The convolutions or folds are absent in sheep brain. Olfacory bulb is more developed in shhep's brain as compared to human brain. Sheep brain is more elongated in shape.
Human brain:
Human brain is large in size. The convolutions are more numerous in human brain. Human's brain olfactory bulb is less developed as compared with sheep's brain. Human brain is round in shape.
One of the reasons we eat food is to gain energy. How can we calculate the amount of energy that a food contains?
Answer:
By calculating the total calorific value of each food ingredients
Explanation:
Food’s energy content is due to its calorific values or the amount of calories it it. Carbohydrate, protein and fat are the major constituents of a food. Suppose, the amount of carbohydrate, protein and fat intake in an adult is equal to X, Y and Z grams
In one gram of carbohydrate , protein and fat there are 4 , 4 and 9 calories per gram
Thus, the total calories in the food of adult will be equal to
[tex](X * 4 + Y * 4 + Z* 9)[/tex] calories
Which muscle is deeper in the body: the internal oblique muscle or the transverse abdominal muscle?
Answer:
Transverse abdominal muscle
Explanation:
Both internal oblique muscle and transverse abdominal muscles are muscles of abdominal wall and are present in pairs. The fascicles of the internal oblique muscle extend towards those of external oblique muscles. Therefore, the internal oblique muscle is closer to skin.
Transverse abdominal muscle is deep muscle of abdominal wall. Its fascicles are arranged around the abdominal wall. This makes it deeper than internal oblique muscle.
The 3 vital centers in the CNS are located in:
a. Pons
b. Cerebral cortex
c. Midbrain
d. Medulla oblongata
e. Cerebral peduncles
Answer:
Medulla oblongata
Explanation:
Medulla oblongata is the part of hindbrain and have three vital centers located in it. The vital centers present in medulla are:
1. Cardiac center
2. respiratory center
3. and vasomotor center.
The cardiac center is also known as cardio inhibitory center and is involved in regulation of heart beat. The basic rhythm of breathing is under regulation of respiratory center while diameter of blood vessels is regulated by vasomotor center.
They are about twice the size of red blood cells and turn into a macrophage when they migrate out of the blood into the tissues.
A. Lymphocytes
B. Neutrophils
C. Monocytes
D. Eosinophils
Answer:
C. Monocytes
Explanation:
Monocytes are 10-24 micrometer in diameter as compared to red blood cells which are only 7-8 micrometer in diameter. Monocytes are one of the agranular leukocytes and transform into macrophages when they migrate from blood to tissues. Their function is to kill the pathogens and cellular debris by the process of phagocytosis.
A decrease in ones perception of a stimulus whose intensity has not changed due to higher neural inhibition is
a. habituation.
b. convergence.
c. divergence.
d. Adaptation
e. Illusion
Answer:
Habituation.
Explanation:
Habituation may be defined as a form of simple learning in which the innate response of an individual perception decreases after repeated stimulation. Some components of organisms are involved in the habituation learning.
The individual response towards a particular stimulus decreases if the same stimuli is repeated over again and again or the stimulus of same intensity. Neural inhibition maintains the stimulus intensity.
Thus, the correct answer is option (a).
On which bone does Mandibular Fossa occurs?
Answer:
Mandibular Fossa occurs on temporal bone.
Explanation:
Mandibular fossa also known as glenoid fossa, the depression of temporal bones. Mandibular fossa articulates with the mandible and interacts with mandibular condyle. Glaserian fissure divides the mandibular fossa into two parts.
Articular tubercle bounds the mandibular fossa anteriorly. The mandibular fossa is bounded posteriorly by the temporal bone. Mandibular fossa development may get arrested due to the separation of mandibular condyle.
Which of the following would be true according to Bergmann’s and Allen’s rules?
a. The Berbers of Morocco have long limbs to absorb heat.
b. The Inuit in Greenland are tall and long-limbed.
c. The Yupik of Alaska have short, squat bodies to retain heat.
d. The Igbo of Nigeria have short, squat bodies to dissipate heat.
Answer:
c. The Yupik of Alaska have short, squat bodies to reatin heat
Explanation:
Acoording to Bergmann's and Allen's rules, the appearance of the humans directly depends on the environment in which they live. The main reason for this rules are that the humans have to develop certain advantageous traits in order to be able to survive in certain type of environment. The Yupik people of Alaska are a nice example of this. The climate in Alaska is very cold. There's lot of snow and long winters with freezing temperatures. The winds are also strong and cold. This has resulted in the Yupik people developing shorter bodies. They also became stockier, with wider chest, larger lung capacity, and also preserving fat below the eyes. These adaptations have been result of the environment, as the type of body they have helps in preserving the heat. The fat below the eyes helps prevent damage to the eyes from the cold, and the larger lung capacity helps them in breathing in colder air.
When the charge inside the cell returns to the resting potential following depolarization, it is called:
Answer:
Repolarization
Explanation:
Repolarization refers to the phase during which the resting potential is restored after depolarization. This means that the inside of the axon membrane becomes negative again compared to the outside.
Repolarization is obtained by the functioning of K+ ion channels. The opening of K+ ion channels allows the K+ to move outside of the axon. Movement of positively charged ion (K+) outside of axon makes the inside negative again and the resting potential is restored.
Muscle that is involuntary and branches is
a. cardiac
b. skeletal
c. smooth
d. visceral
Answer:
Cardiac muscle.
Explanation:
Cardiac muscle is also known as heart muscle. These muscles regulate the proper working and functioning of the heart.
Cardiac muscles are involuntary muscles and show striations under the microscope. These muscles are uninucleate and connected by the intercalated disc. Cardiac muscles are branched so that each cardiac cells may attach with atleast with or four other cardiac cells.
Thus, the correct answer is option (A).
What is the hole in the center of the iris? What is its function?
Answer:
Pupil
Function: serves as site for entry of light into the eyeball.
Explanation:
The hole in the center of the iris is called pupil. The light enters the eyeball through the pupil. The pupil is circular or oval in shape and appears mostly black in color. With the help of muscular iris, the size of the pupil changes according to the intensity of incoming light.
Hence, the pigmented portion of the eyes of vertebrates (the iris) has a hole in its center called pupil to allow the light to enter the eyeball.