1.
One type of organism has some photosynthetic members but is primarily unicellular. They do have a true nucleus and organelles. Into which kingdom does this organism most likely belong?
Correct Answer
A. Protists
Explanation
This organism is most likely a member of the kingdom Protists because it is primarily unicellular, has a true nucleus, and organelles. Protists are a diverse group of eukaryotic microorganisms that can be unicellular or multicellular, and they include various types of algae, protozoa, and slime molds.
2.
Which of the following is NOT used to determine the phyla to which a plant belongs?
Correct Answer
C. Presence of chloroplasts
Explanation
The presence of chloroplasts is not used to determine the phyla to which a plant belongs. Chloroplasts are present in most plants and are responsible for photosynthesis. However, the presence or absence of chloroplasts does not provide information about the classification of plants into different phyla. Other characteristics such as the absence of a vascular system, presence of seeds, and absence of flowers are commonly used to determine the phyla to which a plant belongs.
3.
A heterozygous that has a selective advantage over the homozygous dominant individual, is an example of ------.
Correct Answer
C. Dominant lethal
Explanation
A heterozygous individual that has a selective advantage over the homozygous dominant individual indicates that the dominant allele is lethal in homozygous form. This means that individuals who carry two copies of the dominant allele will not survive, while individuals who carry one copy of the dominant allele and one copy of the recessive allele will have a selective advantage and survive. Therefore, this situation is an example of dominant lethal inheritance.
4.
Which of the following lists characteristics of a dicot?
Correct Answer
B. Two cotyledons, a tap root and a branched leaf veins.
Explanation
The correct answer is "Two cotyledons, a tap root and a branched leaf veins." This answer is correct because it accurately lists the characteristics of a dicot. Dicots are plants that have two cotyledons, which are the embryonic leaves in a seed. They also have a tap root system, which is a main root that grows vertically into the ground, and branched leaf veins, which can be seen in the pattern of veins on the leaves.
5.
Which of the following traits do lizards and adult salamanders have in common?
Correct Answer
B. Jaws, lungs
Explanation
Lizards and adult salamanders have jaws and lungs in common. Both reptiles have jaws that allow them to eat and catch prey, and lungs that enable them to breathe air. While lizards have scaly skin, and salamanders have wet skin, these are not traits they share in common. Similarly, neither lizards nor salamanders have fur or feathers, so these traits are not applicable to them.
6.
Which kingdoms include both unicellular and multicellular organisms?
Correct Answer
A. Fungi and plants
Explanation
Fungi and plants are the kingdoms that include both unicellular and multicellular organisms. Fungi include both unicellular yeasts and multicellular molds and mushrooms. Plants include both unicellular algae and multicellular land plants. Therefore, the correct answer is Fungi and plants.
7.
Organisms that are members of the same order must also be members of the same ......
Correct Answer
B. Class
Explanation
Organisms that are members of the same order must also be members of the same class. In biological classification, the order is a higher taxonomic rank than the genus, species, and family. It groups together organisms that share similar characteristics and are more closely related to each other. The class, on the other hand, is a higher taxonomic rank than the order, and it includes a broader range of organisms that share common characteristics. Therefore, if organisms belong to the same order, they must also belong to the same class.
8.
Types of gametes produced by a homozygous individual is -------.
Correct Answer
A. One
Explanation
A homozygous individual has two identical alleles for a particular gene. Therefore, they can only produce one type of gamete, as both alleles are the same.
9.
In Drosophila, if you cross a red-eyed male with a white-eyed female, all the male offspring would be ____ and all the female ones would be _____.
Correct Answer
D. White eyed, red eyed
Explanation
When a red-eyed male is crossed with a white-eyed female in Drosophila, all the male offspring would be white-eyed. This is because the gene for eye color is located on the X chromosome, and in Drosophila, females have two X chromosomes while males have one X and one Y chromosome. The red eye color is dominant and is carried on the X chromosome. Since males only inherit one X chromosome from their mother, if it carries the white eye color gene, they will express the white eye color. On the other hand, all the female offspring would be red-eyed because they inherit one X chromosome from each parent, so even if they inherit the white eye color gene from their mother, they will also inherit the red eye color gene from their father, resulting in red eye color.
10.
In the following pedigree, if you know that the yellow gene (A) dominates the green one (a), then the genotype of the member number (1) is --------.
Correct Answer
D. AA or Aa
Explanation
Based on the information given, the yellow gene (A) dominates the green gene (a). This means that if an individual has at least one copy of the yellow gene (A), it will express the yellow phenotype. Therefore, the genotype of member number (1) can be either AA or Aa, as both genotypes have at least one copy of the dominant yellow gene (A).
11.
Genetic cases where two different phenotypes having the same genotype .......
Correct Answer
B. Sex-influenced and sex-limited
Explanation
Sex-influenced and sex-limited are two genetic cases where two different phenotypes can have the same genotype. In sex-influenced inheritance, the expression of a trait is influenced by the sex of the individual. For example, male pattern baldness is more common in males than females, even though the gene for baldness is present in both sexes. In sex-limited inheritance, the expression of a trait is limited to one sex. For example, milk production in mammals is limited to females. Therefore, both sex-influenced and sex-limited inheritance can result in different phenotypes with the same genotype.
12.
A non-disjunction is the failure of homologous chromosomes or sister chromatids to separate during gamete formation. If a turner hemophiliac child born to normal parents. So where did the non-disjunction occur?
Correct Answer
A. Father
Explanation
The non-disjunction likely occurred in the father. Non-disjunction is the failure of chromosomes to separate properly during gamete formation. Since the child is a turner hemophiliac, it suggests that the father's sperm had an extra X chromosome, resulting in the child's condition.
13.
The genotypes of a husband and wife are AB and AO. Among the blood types of their children, how many different genotypes and phenotypes are possible?
Correct Answer
D. 4 genotypes; 3 pHenotypes
Explanation
The genotypes of the husband and wife are AB and AO. The possible genotypes of their children can be AA, AB, AO, and BO. Therefore, there are 4 possible genotypes. However, when it comes to phenotypes, the blood types of the children can be A, B, or O. Since the AB genotype results in the AB blood type, there are only 3 possible phenotypes.
14.
If the gene (A) for a normal character dominates the gene (a) for a certain disease. In the following pedigree, what is the genotype of each of the members I (2) and II (4)?
Correct Answer
D. I (2) is Aa and II (4) is Aa
Explanation
In the given question, it is stated that gene A for a normal character dominates gene a for a certain disease. This means that the presence of gene A will mask the presence of gene a, resulting in a normal phenotype. Member I (2) is genotype Aa, which means that they have one copy of gene A and one copy of gene a. Member II (4) is also genotype Aa, indicating that they also have one copy of gene A and one copy of gene a. This is the only option where both individuals have the same genotype, so it is the correct answer.
15.
Protistans are connecting link between ………..
Correct Answer
C. Monerans and kingdoms of multicellular organisms
Explanation
Protistans are considered to be the connecting link between Monerans (single-celled organisms) and the kingdoms of multicellular organisms (such as plants, animals, and fungi). This is because protistans exhibit characteristics of both single-celled and multicellular organisms. They can be unicellular or multicellular and have features similar to both plants and animals. Therefore, they serve as a transitional group between the simpler Monerans and the more complex kingdoms of multicellular organisms.
16.
The scientific (and common) names of three animals are: Canis familiaris (dog), Canis lupus (wolf), and Vulpes vulpes (fox). These three animals all belong to the same …....
Correct Answer
D. Family but different species
Explanation
The correct answer is "Family but different species" because although these animals belong to the same genus "Canis" (which is a group of closely related species), they belong to different families. The dog belongs to the family Canidae, the wolf belongs to the family Canidae, and the fox belongs to the family Canidae. Therefore, they are in the same family but different species.
17.
Which of the following genotypes represents a dihybrid?
Correct Answer
C. WwSs
Explanation
A dihybrid refers to an individual that is heterozygous for two different traits. In this case, the genotype WwSs represents a dihybrid because it has two different alleles for each of the two traits being considered (Ww for one trait and Ss for the other).
18.
An adult organism is found to have no feathers or fur and to breathe via lungs, not gills. Using the key shown in the figure below, the organism ......
Correct Answer
D. Could be either a reptile or an ampHibian
Explanation
Based on the given information, the organism does not have feathers or fur and breathes through lungs, which suggests that it is not a bird or a mammal. The key does not provide any specific information about the presence or absence of scales, so it could be a reptile. Additionally, the key does not mention anything about the ability to live on land or in water, so it could also be an amphibian. Therefore, the correct answer is that the organism could be either a reptile or an amphibian.
19.
Use the diagram below that shows the levels of classification for living organisms, to determine the level (E).
Correct Answer
C. Class
Explanation
The diagram shows the levels of classification for living organisms, with Order, Phylum, Class, and Family listed in order. The level (E) refers to the position in the classification hierarchy. Based on the diagram, the level (E) is Class.
20.
If there is a family history of genetic disorders, knowing the gender of an unborn child can be important because .........
Correct Answer
C. C) male children are more likely to have X-linked traits show up in their pHenotype
Explanation
Knowing the gender of an unborn child can be important in the context of a family history of genetic disorders because male children are more likely to have X-linked traits show up in their phenotype. This is because males have only one X chromosome, making them more susceptible to inheriting and expressing X-linked disorders. On the other hand, females have two X chromosomes, providing a potential protective mechanism against these disorders. Therefore, knowing the gender of an unborn child can help in understanding the likelihood of certain genetic disorders based on their inheritance pattern.
21.
In Mendel's F2 generation, one out of four plants had white flowers because ------.
Correct Answer
B. Both parents were heterozygous purple
Explanation
In Mendel's F2 generation, one out of four plants had white flowers because both parents were heterozygous purple. This means that both parents carried the gene for purple flowers, but also carried a recessive gene for white flowers. When these two heterozygous parents are crossed, there is a 25% chance that their offspring will inherit two recessive genes for white flowers, resulting in white flowered plants.
22.
A soft-bodied, invertebrate animal could NOT belong to the phylum .......
Correct Answer
C. Arthropoda
Explanation
A soft-bodied, invertebrate animal could NOT belong to the phylum Arthropoda because Arthropods have a hard exoskeleton made of chitin, which provides support and protection to their body. Soft-bodied animals, on the other hand, lack this exoskeleton and have a more flexible body structure. Therefore, it is not possible for a soft-bodied animal to belong to the phylum Arthropoda.
23.
When sex cells combine to produce offspring, each sex cell will contribute --------.
Correct Answer
B. Half the normal number of chromosomes
Explanation
During the process of sexual reproduction, two sex cells (gametes) combine to form an offspring. Each sex cell contributes half of the genetic material, including chromosomes, to the offspring. This ensures that the offspring receives a balanced and complete set of chromosomes, with half coming from each parent. Therefore, each sex cell contributes half the normal number of chromosomes.
24.
The figure below shows the digits of one of the front legs in a Dog. What is the proper classification of the dog?
Correct Answer
C. Carnivora
Explanation
Based on the figure provided, it is not possible to determine the proper classification of the dog. The figure only shows the digits of one of the front legs, which is not enough information to classify the dog accurately. Therefore, the correct answer cannot be determined from the given information.
25.
A recessive allele (t) is responsible for a condition called dystonia. A man who has this condition marries a woman, where no one of their three children has the condition. What are the possible genotypes of the man and woman?
Correct Answer
D. The father is tt; the mother may be Tt or TT
Explanation
The condition dystonia is caused by a recessive allele (t). The fact that none of their three children have the condition indicates that they are not homozygous recessive (tt). Therefore, the father must be heterozygous (Tt). The mother can either be homozygous dominant (TT) or heterozygous (Tt) since both genotypes would result in none of their children inheriting the condition. Therefore, the possible genotypes for the man and woman are the father being tt and the mother being either Tt or TT.
26.
Which is the correct genetic pattern for the following figures A, B, C, D, and E respectively?
Correct Answer
B. Law of segregation / incomplete dominance / Dominant lethal / Complementary genes / Independent assortment
27.
The probability of producing heterozygous offspring from crossing a heterozygous parent with another homozygous dominant parent for a particular trait would be --------.
Correct Answer
C. 50%
Explanation
When crossing a heterozygous parent with a homozygous dominant parent, the heterozygous parent will contribute one dominant allele and the homozygous dominant parent will contribute two dominant alleles. This means that there is a 50% chance of producing heterozygous offspring, as there is a 50% chance of the offspring inheriting the dominant allele from the heterozygous parent.
28.
In a family of four including a normal mother, a normal father, a color-blind son and a normal son; who do you think has the defective X gene other than the affected son?
Correct Answer
A. The mother
Explanation
In this scenario, the color-blindness trait is caused by a defective X gene, which is a recessive trait. Since the father is normal, he must have two normal X genes. The affected son inherited one defective X gene from the mother and one normal X gene from the father. The normal son inherited two normal X genes, one from each parent. Therefore, the only person who can have the defective X gene other than the affected son is the mother.
29.
Homologous chromosomes may differ in --------.
Correct Answer
B. Allele composition
Explanation
Homologous chromosomes may differ in allele composition. Alleles are alternative forms of a gene that occupy the same genetic locus on homologous chromosomes. Therefore, homologous chromosomes may have different alleles at the same genetic loci, resulting in variations in allele composition between the chromosomes. This variation in allele composition is one of the factors that contribute to genetic diversity and the differences observed among individuals.
30.
A man of blood type A, whose mother had blood type O, marries a woman of blood type B, whose father was blood type O. The chances of this couple's having a child with blood type O are --------.
Correct Answer
A. 25%
Explanation
The chances of this couple's having a child with blood type O are 25%. This is because both parents have a recessive allele for blood type O. The man has blood type A, which means he has one allele for blood type A and one allele for blood type O. The woman has blood type B, which means she has one allele for blood type B and one allele for blood type O. When they have a child, there is a 25% chance that both parents will pass on their O alleles, resulting in a child with blood type O.
31.
What factors can affect a person's height?
Correct Answer
C. Both genes and environmental factors
Explanation
Both genes and environmental factors can affect a person's height. Genes play a significant role in determining a person's potential height, as certain genes can influence the production of growth hormones and the development of bones. However, environmental factors such as nutrition, exercise, and overall health also play a crucial role in determining how much a person's genes are expressed, ultimately affecting their height. Therefore, it is a combination of both genetic and environmental factors that determine a person's height.
32.
The first eukaryotes to evolve were ………
Correct Answer
D. Protistans
Explanation
Protistans were the first eukaryotes to evolve. Eukaryotes are organisms that have complex cells with a nucleus enclosed by a membrane. Protistans are a diverse group of eukaryotic microorganisms that include various single-celled organisms such as amoebas, paramecia, and algae. They are considered the first eukaryotes because they evolved from prokaryotes, which are simpler organisms without a nucleus. Protistans played a crucial role in the evolution of more complex organisms and are believed to be the ancestors of plants, animals, and fungi.
33.
In domestic chickens, some males show a feathery pattern called cock feathering. Other males and all females show a pattern called hen feathering. Cock feathering is an autosomal recessive trait that is displayed in males only. Two heterozygous birds are mated. What are their PHENOTYPES ?
Correct Answer
D. Male with hen feathering, female with hen feathering
Explanation
The correct answer is "Male with hen feathering, female with hen feathering." This is because cock feathering is an autosomal recessive trait that is only displayed in males. Since both birds are heterozygous, they have one dominant allele and one recessive allele for the cock feathering trait. However, since the trait is recessive, it is not expressed in either bird's phenotype. Therefore, both birds will have the hen feathering pattern.
34.
The gene for Rh+ blood is dominant over the gene for Rh- blood. An Rh+ve woman whose mother was Rh-ve marries an Rh-ve man, both of whose parents were Rh-ve. What percentage of their children will be expected to be Rh+ve?
Correct Answer
C. 50%
Explanation
When the Rh+ve woman marries an Rh-ve man, there is a 50% chance that the woman is heterozygous for the Rh gene (Rh+ve/Rh-ve) and a 50% chance that she is homozygous for the Rh gene (Rh+ve/Rh+ve). If she is heterozygous, there is a 50% chance that each child will inherit the Rh+ve gene from her. If she is homozygous, all of her children will inherit the Rh+ve gene. Therefore, there is a 50% chance that each child will be Rh+ve.
35.
A woman suffers from a hair loss marries a bald man produce a daughter and a son, their daughter has no signs of hair loss but their son is bald, the genotype of the son is -------.
Correct Answer
C. Pure or hybrid bald
Explanation
The woman suffers from hair loss, which means she has the genotype for baldness. The fact that their daughter has no signs of hair loss suggests that she does not have the genotype for baldness. However, their son is bald, indicating that he inherited the genotype for baldness from his mother. Since the mother is known to have the genotype for baldness and the daughter does not, it is likely that the son has a pure or hybrid genotype for baldness. Therefore, the correct answer is "Pure or hybrid bald."
36.
A man married a woman and had four girls. If the woman got pregnant again, what is the probability of the 5th child to be a boy?
Correct Answer
D. 50%
Explanation
The probability of having a boy is 50% because the gender of a child is determined by the combination of chromosomes from both parents. Each parent contributes one chromosome, either X or Y, which determines the gender of the child. Since the man has an equal chance of passing on either an X or Y chromosome, and the woman has an equal chance of passing on either an X or Y chromosome, the probability of having a boy is 50%.
37.
Males tend to inherit more sex-linked conditions because _____.
Correct Answer
B. There is no corresponding alleles on the Y-chromosomes
Explanation
Males tend to inherit more sex-linked conditions because there are no corresponding alleles on the Y-chromosomes. Sex-linked conditions are typically caused by mutations in genes located on the sex chromosomes, with the X chromosome being more commonly associated with these conditions. Since males have one X and one Y chromosome, any mutation on the X chromosome will not have a corresponding allele on the Y chromosome to compensate for it. Therefore, males are more likely to express sex-linked conditions if they inherit the mutated allele on their X chromosome.
38.
Which of the following animals shares a common phylum with the animals in the picture?
Correct Answer
C. Animal C
Explanation
Animal C shares a common phylum with the animals in the picture because all the animals in the picture belong to the same phylum.
39.
The duck-billed shares a common character with the goose in -------.
Correct Answer
D. Both incubate their eggs
Explanation
The correct answer is "Both incubate their eggs." This is because both the duck-billed and the goose share the characteristic of incubating their eggs. Incubation is the process in which the parent bird sits on the eggs to provide warmth and ensure proper development. This behavior is common among many bird species, including ducks and geese.
40.
What will be the phenotype and genotype of a daughter born to a bald mother and non-bald father?
Correct Answer
C. B B+ non-bald
Explanation
The phenotype refers to the physical characteristics or traits that are expressed, while the genotype refers to the genetic makeup of an individual. In this case, the mother is bald, which suggests that she carries the recessive allele for baldness (b). The father is non-bald, indicating that he does not carry the recessive allele. Since baldness is a recessive trait, the daughter will need to inherit two copies of the recessive allele (bb) from both parents in order to express the phenotype. However, since the father does not carry the recessive allele, the daughter will inherit one dominant allele (B) from him, making her genotype Bb. This means that she will not be bald, as the dominant allele masks the expression of the recessive allele.
41.
One of the following common characteristics between the Kangaroo and the Deer is NOT true -----.
Correct Answer
A. Both are placental mammals
Explanation
The correct answer is "Both are placental mammals." This is because while kangaroos are marsupials, which means they give birth to relatively undeveloped young and then carry them in a pouch, deer are placental mammals and give birth to fully developed young.
42.
The graph below shows the time of origin and the complexity of four different living organisms, (Trypanosoma, Rhizopus nigricans, Polysiphonia and Coccus bacteria ). To which of them the letter (A) refers -------.
Correct Answer
B. Rhizopus nigricans
43.
If a male inherits a sex-linked gene for color blindness ______.
Correct Answer
A. It always be expressed
Explanation
If a male inherits a sex-linked gene for color blindness, it will always be expressed. This is because males only have one X chromosome, and if they inherit a color blindness gene on that chromosome, they do not have another X chromosome to compensate for it. Unlike females, who have two X chromosomes and can have one normal gene to compensate for the color blindness gene, males do not have this option. Therefore, if a male inherits a sex-linked gene for color blindness, it will always be expressed.
44.
If the father of a fetus is Rh positive and the mother is Rh negative, what are the chances that there will be a mother-fetus incompatibility problem? Assume that the couple has already had a child Rh+ve and that there has been no medical treatment to prevent this problem.
Correct Answer
B. At least 50%
Explanation
When the father is Rh positive and the mother is Rh negative, there is a possibility of mother-fetus incompatibility problem because the fetus can inherit the Rh positive factor from the father. This can lead to the mother's immune system producing antibodies against the Rh positive factor, which can cause complications in future pregnancies. Therefore, there is at least a 50% chance of a mother-fetus incompatibility problem in this scenario.
45.
Heterozygous parents who have had one child with a recessive disease will still have a ____ chance of their second child being born with the same recessive disease.
Correct Answer
D. 25%
Explanation
When both parents are heterozygous, it means that they carry one copy of the recessive disease allele and one copy of the dominant allele. In this case, each parent has a 50% chance of passing on the recessive allele to their child. Therefore, the chance of both parents passing on the recessive allele to their second child is 0.5 x 0.5 = 0.25, or 25%.
46.
In a certain genetic trait some genes are switched on in one of the two sexes while they are switched off in the other sex. For example only males can have prostate cancer and only females can have ovarian cancer, although both males and females can carry the genes for these conditions. So this trait is a …………
Correct Answer
B. Sex-limited trait
Explanation
In this genetic trait, certain genes are switched on in one sex and switched off in the other sex. This means that the expression of the trait is limited to one sex. For example, only males can have prostate cancer and only females can have ovarian cancer, even though both sexes can carry the genes for these conditions. Therefore, this trait is a sex-limited trait.
47.
What are the two genetic cases (A) and (B) shown in the figure below?
Correct Answer
A. A is independent assortment / B is complete linkage
Explanation
The figure likely shows the results of a genetic cross between two traits. In case A, the traits are independently assorted, meaning that they segregate independently during gamete formation. In case B, the traits show complete linkage, meaning that they are located close together on the same chromosome and tend to be inherited together.
48.
Vascular bundles are not found in …….
Correct Answer
D. BryopHytes
Explanation
Bryophytes are non-vascular plants, meaning they do not have specialized tissues for transporting water and nutrients throughout the plant. Vascular bundles, on the other hand, are present in gymnosperms, pteridophytes, and angiosperms. These bundles consist of xylem and phloem tissues that help in the transportation of water, minerals, and sugars. Therefore, the absence of vascular bundles in bryophytes is the correct answer.