I need some help with these questions. I've chosen answers, but I want to make sure if they are correct.
1)Which of the following is an acidic pH?
6
7
8
800
A: 6
None of the above
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2) Which of the following is directly produced by photosynthesis?
Glucose and oxygen
Carbon dioxide and water
Oxygen and water
Glucose and carbon dioxide
Energy in the form of ATP
A: Glucose and Oxygen
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3) A bacterium lacks which of the following structures or components?
Plasma membrane
Cell wall
Ribosomes
DNA
Nucleus
A: Nucleus
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4) The plasma membrane is made up of which of the following?
Protein only
Protein and RNA
Phospholipids only
Phospholipids and proteins
DNA only
A: Phospholipids and Proteins
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5) Which statement about linkage of genes is false?
Genes on the same chromosome are said to be linked
Genes on the same chromosome assort independently
Crossing over between two linked genes can alter phenotypes of progeny
Crossing over results in recombinant phenotypes
Genes on the same chromosome that are far apart have a higher recombination frequency than those that are close together
A: Genes on the same chromosome assort independently
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6) Genes located on mitochondrial DNA are usually inherited
randomly.
from the mother.
from the father.
evenly from both the mother and the father.
by independent assortment.
A: from the mother
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7) Which component is required for the initiation of transcription?
The start codon AUG
Promoter DNA sequence
Ribonucleoside triphosphates
Terminator DNA sequence
DNA polymerase
A: Promoter DNA
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8) Put the following four steps of eukaryotic gene expression in order, from beginning to end.
(1) Pre-mRNA is processed to make mRNA.
(2) Ribosomes translate the mRNA sequence to make proteins.
(3) mRNA is transported to the cytoplasm.
(4) DNA is used as a template to make pre-mRNA.
1; 4; 3; 2
4; 3; 1; 2
4; 1; 3; 2
4; 1; 2; 3
1; 2; 4; 3
A: 4,1,3,2
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9) RNA polymerases differ from DNA polymerases in that
RNA polymerases do not require a template
RNA polymerases use deoxyribonucleoside triphosphates as substrates
DNA polymerases use ribonucleoside triphosphates as substrates
RNA polymerases are less effective at proofreading than DNA polymerases
Only DNA polymerases are processive
A: RNA polymerases are less effective at proofreading than DNA polymerases
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10) The site on the chromosome occupied by a gene is called
Allele
Region
Locus
Type
Phenotype
A: Locus
Here are the explanations for each question:
1) Which of the following is an acidic pH?
The correct answer is 6. To determine if a pH is acidic, basic, or neutral, you need to know the pH scale. The pH scale ranges from 0 to 14, where 0 is highly acidic, 7 is neutral, and 14 is highly basic (alkaline). In this case, a pH of 6 is acidic, so the answer is 6.
2) Which of the following is directly produced by photosynthesis?
The correct answer is Glucose and Oxygen. In photosynthesis, plants and other organisms convert light energy into chemical energy in the form of glucose and release oxygen as a byproduct. So, the answer is Glucose and Oxygen.
3) A bacterium lacks which of the following structures or components?
The correct answer is Nucleus. Bacteria are prokaryotes, which means they lack a nucleus. Prokaryotes have their genetic material, DNA, scattered in the cytoplasm without a membrane-bound nucleus like eukaryotic cells.
4) The plasma membrane is made up of which of the following?
The correct answer is Phospholipids and Proteins. The plasma membrane of cells is composed of a phospholipid bilayer with proteins embedded within it. Phospholipids make up the basic structure of the membrane, while proteins perform various functions like transport, signaling, and cell adhesion.
5) Which statement about linkage of genes is false?
The false statement is "Genes on the same chromosome assort independently." Genes located on the same chromosome are called linked genes. They tend to be inherited together unless separated by a process called crossing over during meiosis. Therefore, the correct answer is "Genes on the same chromosome assort independently."
6) Genes located on mitochondrial DNA are usually inherited
The correct answer is "from the mother." Mitochondrial DNA is primarily inherited from the mother. During fertilization, only the egg contributes mitochondria to offspring, while sperm mitochondria are usually excluded. This results in maternal inheritance of mitochondrial DNA.
7) Which component is required for the initiation of transcription?
The correct answer is "Promoter DNA sequence." Transcription is the process of synthesizing RNA from a DNA template. It starts at specific DNA sequences called promoters, which signal the initiation of transcription by RNA polymerase.
8) Put the following four steps of eukaryotic gene expression in order, from beginning to end.
The correct order is 4; 1; 3; 2. The steps are as follows:
(1) DNA is used as a template to make pre-mRNA (transcription).
(2) Pre-mRNA is processed to make mRNA (RNA processing).
(3) mRNA is transported to the cytoplasm (mRNA transport).
(4) Ribosomes translate the mRNA sequence to make proteins (translation).
9) RNA polymerases differ from DNA polymerases in that
The correct answer is "RNA polymerases are less effective at proofreading than DNA polymerases." RNA polymerases are enzymes responsible for synthesizing RNA using DNA as a template. Compared to DNA polymerases, RNA polymerases have a higher error rate during RNA synthesis and are less effective in proofreading and correcting errors.
10) The site on the chromosome occupied by a gene is called
The correct answer is "Locus." A locus refers to a specific position on a chromosome where a particular gene is located. It represents the physical location or address of a gene within the genome.