WorksheetsBiology sem 1 finals practice
Total questions: 83
Worksheet time: 42mins
A scientist observes that when she opens the back door of her house to let her cat out, the songs of a certain species of bird abruptly change. She wants to follow up on her observations with an experiment. Which of the following is the best hypothesis for explaining the birds’ song changes?
The bird species switches from song to warning call whenever it sees a potential enemy.
The bird species has a variety of songs that it sings, regardless of what is happening in its environment.
The scientist is mistaken and the songs do not change.
A scientist wishes to test a new antibiotic’s ability to treat stubborn bacterial infections. He tests his hypothesis that the antibiotic works better than existing treatments by giving bacterial infections to mice and treating them with the antibiotic. He then determines how many of the mice recover from their infections. What is missing from his experimental design?
He is missing a control group of mice that received a half dose of the new antibiotic.
He is missing a control group of mice that did not receive the new antibiotic.
Nothing is missing—he has done everything he needs to do for this to be a successful experiment.
Why are theories stronger and more reliable than hypotheses?
because we believe in them more
because they are based on many experimentally tested hypotheses
because theories are educated guesses.
Which of the following statements correctly identifies and describes the type of bond found between oxygen and hydrogen in neighboring water molecules, shown as a dashed line here?
polar covalent bonds because hydrogen is more electronegative than oxygen
ionic bonds because oxygen is more electronegative than hydrogen
hydrogen bonds because oxygen is more electronegative than hydrogen
Proteins have a unique shape which can be seen in their tertiary structures. The shape of the protein relates to its function.
True
False
Why are amino acids called “amino acids?”
They are single molecules that contain both an amine group and a carboxylic acid group.
They are subunits of macromolecules that act as both strong acids and strong bases in solution.
They are acidic and were first discovered by a Russian researcher by the name of Aminov.
Which of the following macromolecules are made from simple sugars?
proteins
complex carbohydrates
nucleic acids
Fatty acids are a component of what type of macromolecule?
lipids
complex carbohydrates
nucleic acids
Which of the following is NOT a function of lipids?
store and transmit hereditary information
store energy
cushioning the organs from mechanical shock
What level of protein structure is associated with the alpha helix and beta-pleated sheet?
primary
secondary
tertiary
Explain why cooked egg white never turns back into the clear egg white seen in a raw egg.
because the protein is denatured in raw egg white
because the protein is denatured in cooked egg white
because the denaturing of the egg proteins is not reversible
Which of the following is not a component of a nucleotide?
nitrogenous base
fatty acid
sugar
Where is most of the DNA found in the cell?
nucleus
mitochondria
Golgi apparatus
Why do water molecules have difficulty crossing a phospholipid bilayer?
they are too big
they are too nonpolar
they are too polar
Which type of microscope can be used to view cellular organelles such as the endoplasmic reticulum and Golgi apparatus?
light microscope
transmission electron microscope
scanning electron microscope
Which if the following are found in eukaryotic cells but not prokaryotic cells?
Nucleus
Cell membrane
ribosomes
Prokaryotic cells include bacteria and they do not have a nucleus.
True
False
What is the major component of the plant cell wall?
starch
glycogen
cellulose
Which of the following carbohydrates is used to store energy in animal cells?
starch
glycogen
cellulose
What process makes bread dough rise?
glycolysis
oxidative phosphorylation
fermentation
Which type of cellular respiration would you expect to find inside a jar full of Greek yogurt?
Alcoholic fermentation
Lactic acid fermentation
Aerobic respiration
Celery sticks and papers contain the same polysaccharide. What is it?
Cellulose
Starch
Glucose
Enzymes bring down the activation energy of a biochemical reaction. They are recovered unchanged at the end to help more such reactions. Enzymes can thus be called -
Hereditary materials
Structural polymers
Biological catalysts
The pentose sugar present in DNA is called the -
Deoxyribose
Sucrose
Ribose
Which of the following statements is true?
The nitrogen base absent in RNA is Adenine.
DNA is double-stranded and RNA is single-stranded
RNA strands are antiparallel and DNA strands are parallel
Identify the amino acid :
What is the main function of the Golgi Body?
It maintains turgor pressure
It modifies, sorts, and ships proteins for export or for use inside the cell.
It controls the hereditary information
Which of these is a possible explanation for the presence of a rigid cell wall in plants?
Plants remain exposed to changes in temperature and thus require rigid cell walls to protect themselves.
Plants are subjected to water pressure and a cell wall helps them against bursting or shrinking.
Plant cells have a rigid cell wall to protect themselves from grazing animals.
I am a big water-filled organelle in plants. My membrane has a fancy name - 'Tonoplast'
Vacuole
Plasmodesmata
Golgi apparatus
I am a secret passage through the plant cells only.
Vacuole
Plasmodesmata
Golgi apparatus
I am a stitch-like watertight seal between fluid filled animal tissues like urinary tract
Tight junction
Mitochondria
Golgi apparatus
I am a stitch-like watertight seal between fluid filled animal tissues like urinary tract
Tight junction
Mitochondria
Plasmodesmata
I break down macromolecules from food like carbs and proteins and release a large amount of ATP. I 'power' the cell.
Vacuole
Golgi apparatus
Mitochondria
Chitin is used as surgical thread and is found in the cell wall of -
Bacteria
Fungi
Plants
Identify the organelle in the image :
Chloroplast
Nucleus
Endoplasmic reticulum
Identify the homologous chromosome of chromosome number 1.
3
4
5
Can 3 be a homologous chromosome for 1? Why or why not?
Yes because they have the same position of centromere.
No, even though the genes are almost at the same position in both, they are not the same genes.
No, because they don't have the same position of centromere.
Sometimes prokaryotic cells like bacteria have an extra piece of circular DNA in their cells. This extra piece of DNA is called -
Nucleoid
Nucleus
Plasmid
A proton gradient is created in mitochondria during cellular respiration because it is required to operate the ATP synthase. Energy from high-energy electrons is used to pump protons actively into the -
Inner mitochondrial membrane
Intermembrane space
Cristae
What is the Mendelian principle of independent assortment?
When diploid organisms make gametes, each gamete receives only one copy of an allele.
During metaphase 1, the arrangement of each homologous pair of chromosome is random with respect to each other.
When dominant and recessive alleles are present as a pair, dominant masks the recessive.
Which of the following type of cells will be closer to its Hayflick limit?
A skin cell in a 70-year old lady
A red blood cell in an infant
A brain cell in a 40-year old doctor.
A normal cell spends most of its time in interphase. What can you conclude from this?
During interphase, the stages prophase, metaphase, anaphase and telophase happen. It takes longer than other phases.
During interphase, DNA and all organelles are replicated after that there are checkpoints for quality control. It takes longer than other phases
During interphase, there are checkpoints for quality control. It takes longer than other phases.
Cancer cells are practically immortal because they can keep dividing forever. This is possible because -
They can keep dividing even when there are other cells close by.
They have their own telomerase which keeps adding new telomeres to the chromosomes.
They can stimulate blood supply and deviate veins near the growth.
The cell below is about to start the process of meiosis. At the end of meiosis, how many chromosomes will the resulting gametes have?
8
4
16
Gregor Mendel is called the Father of Modern Genetics because -
He formulated the three principles of heredity which are universally applicable.
He discovered what genes are and experimented with peas to prove it.
He formulated the right pattern of inheritance of human blood groups.
Ed has a heterozygous type A blood group and Cherry has heterozygous type B blood group.
What is the probability that their baby Lyra has a type B blood group?
50%
25%
75%
Is it possible for a mom with type AB blood group and a dad with type A blood group to have a baby with type O blood group? Why?
Yes because dad can be heterozygous type A
No because for the baby to have O, both parents must have at least one 'i'
No because the mom can still have a genotype of IA i
In the diagrammatic representation of DNA replication below, triangle shape labeled '2' is the enzyme that unwinds/opens up the DNA double helix. What is it's name?
Primase
Single strand binding proteins
Helicase
Enzyme that builds DNA strands but can only add on to existing strands
DNA Polymerase
Primase
Okazaki fragments
Primer
Ligase
Enzyme that creates a complementary RNA fragment next to the DNA about to be replicated
DNA Polymerase
Primase
Okazaki fragments
Primer
Ligase
The fragments of lagging strand
DNA Polymerase
Primase
Okazaki fragments
Primer
Ligase
Small fragments of RNA that the DNA polymerase adds nucleotides to
DNA Polymerase
Primase
Okazaki fragments
Primer
Ligase
Enzyme that connects two fragments to close the gap between them
DNA Polymerase
Primase
Okazaki fragments
Primer
Ligase
The DNA replication model can be called -
Dispersive
Semi conservative
Conservative
In meiotic prophase, homologous chromosomes pair up and exchange parts of their genes. This process is the one of the sources of variation in sexually reproducing organisms. What is this process called?
Random fertilization
Independent assortment
Crossing over
If haploid number is 'n' and diploid number is '2n', in approximately how many different combinations of chromosomes can result in meiosis?
n2
2n
2n2
Mature human nerve cells never divide. Two common neurological disorders - Alzheimer’s and Parkinson’s result due to degeneration of nerve cells.
Why are these diseases progressive and cannot be cured by medications?
The damage caused by these disorders cannot be compensated because antibiotics do not work in the brain.
The degenerated nerve cells cannot be repaired because mature nerve cells do not undergo mitosis.
These diseases are progressive because nerve cells divide uncontrollably and become cancerous.
Why are prolonged exposures to both tanning booths and sun without sunscreen can be equally life-threatening?
Both produce ultraviolet radiation which can cause melanoma in the skin
Both produce gamma rays that can damage the tissues in the heart.
Both produce infra red radiation that can cause the skin to tan irreversibly.
What is one key difference between prokaryotic and eukaryotic DNA?
Prokaryotic DNA is present within chromosomes. Eukaryotic DNA is present in the nucleus.
Prokaryotic DNA is not associated with histones. Eukaryotic DNA is intricately packaged with histones.
Prokaryotic DNA does not have deoxyribose. Eukaryotic DNA has deoxyribose.
A pigeon zygote contains 80 chromosomes.
How many chromosomes did the zygote receive from its mother?
40
20
80
A hedgehog has a chromosome number of 2n = 34.
Which of the following is true?
The species is diploid with 34 pairs of chromosomes.
A gamete from this species is haploid with 17 chromosomes.
The species is haploid with 34 homologous pairs.
Homologous pairs line up in the center of the cell.
Prophase I
Metaphase I
Metaphase II
Crossing over occurs.
Prophase I
Metaphase I
Metaphase II
Chromosomes line up in single file in equatorial plane
Prophase I
Metaphase I
Metaphase II
Which of the following are true regarding the process of meiosis?
Chromosome number is reduced from diploid to haploid.
Homologue pairs do not have any crossovers during prophase I.
Sister chromatids in a cell undergoing meiosis are always exactly identical.
Which of the following are true regarding the process of mitosis?
Chromosome number is reduced from diploid to haploid.
Chromosome number remains exactly the same as it was before mitosis.
4 daughter cells are made from one cell in one division.
Which statement correctly describes the offspring of asexual reproduction?
They are exact clones of each other and their parents.
They have variations because of crossing over.
Asexual reproduction involves meiosis to make gametes.
What type of vegetative reproduction is shown in the image of Hydra below?
Binary fission
Budding
Meiosis
The diagram below shows a cell moving from one phase of meiosis to another.
Which of the following best describes what happens during the phases of meiosis shown in the diagram?
Chromosomes that have already undergone crossing over line up in the middle of the cell, and then sister chromatids separate.
Attached homologous chromosomes line up in the middle of the cell, and then individual chromosomes separate.
Chromosomes extend from the poles of the cells and separate the structures that have aligned at the center.
Which of the following are overall products of cellular respiration?
ATP and carbon dioxide
Oxygen and ATP
Glucose and oxygen
What are the three main stages of aerobic cellular respiration?
Glycolysis, Krebs cycle, electron transport chain (oxidative phosphorylation)
Krebs cycle, fermentation, glycolysis
Electron transport chain (oxidative phosphorylation), glycolysis, fermentation
On a cool and brisk day, if you take a deep breath in and then exhale, you'll see a "fog" that forms as a result of your exhaled breath.
Which of the following products of cellular respiration does that "fog" contain?
Oxygen and water
Carbon dioxide and water
Oxygen and carbon dioxide
What is the role of oxygen in cellular respiration?
Oxygen promotes glycolysis
Oxygen is required for photosynthesis
Oxygen is the final electron acceptor in ETC
Both autotrophs and heterotrophs perform this process
Photosynthesis
Cellular respiration
Fermentation
A process where cells break down food molecules (glucose) to release energy they contain.
Photosynthesis
Cellular respiration
Fermentation
It is a process for cells to obtain energy from sugar in the absence of oxygen. There are two types.
Photosynthesis
Cellular respiration
Fermentation
Commercially important process used in baking, brewing, making yogurt and cheese.
Photosynthesis
Cellular respiration
Fermentation
Only autotrophs can perform this process
Photosynthesis
Cellular respiration
Fermentation
How many chromosomes are shown in this picture? How many chromatids?
4 chromosomes, 4 chromatids
4 chromosomes, 8 chromatids
8 chromosomes, 4chromatids
Found only in animal cells
Cell wall
centrosome
Mitochondria
Found only in plant cells
Cell wall
centrosome
Mitochondria
Found in both plant and animal cells
Cell wall
centrosome
Mitochondria
Found in both plant and animal cells
Cell wall
centrosome
nucleus
