Biology: Life and Systems

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Cell Theory and Organelles

Subtopic

Cell Theory and Organelles under Biology: Life and Systems for Grade 8 IB.

Preview questions (no answers)

1.
$What is the function of a vesicle in a cell?$
A. $To produce sugar$
B. $To transport materials around the cell$
C. $To hold the DNA$
D. $To provide structural support$
2.
$Which of the following is true regarding the size of cells?$
A. $All cells are large enough to see with the naked eye$
B. $Most cells are microscopic$
C. $Animal cells are always larger than plant cells$
D. $Prokaryotic cells are larger than eukaryotic cells$
3.
$Which part of the microscope is the lens you look through at the top?$
A. $Objective lens$
B. $Ocular lens$
C. $Condenser$
D. $Base$
4.
$Which cell structure is described as 'semi-permeable'?$
A. $Cell wall$
B. $Cytoplasm$
C. $Cell membrane$
D. $Nucleus$
5.
$Which structure allows for communication and transport between adjacent plant cells?$
A. $Gap junctions$
B. $Plasmodesmata$
C. $Tight junctions$
D. $Desmosomes$
6.
$Why is the nucleus often referred to as the 'control center' of the cell?$
A. $It produces all the energy for the cell$
B. $It contains the instructions for making proteins and cell operation$
C. $It regulates the passage of materials into the cell$
D. $It is located in the exact center of every cell$
7.
$Which organic molecule is the primary component of the 'tails' in the phospholipid bilayer?$
A. $Glycerol$
B. $Phosphate group$
C. $Fatty acids$
D. $Amino acids$
8.
$8 mm$
A. $20 \mu m$
B. $2 \mu m$
C. $200 \mu m$
D. $0.2 \mu m$
9.
$What is the primary function of the middle lamella in plant tissues?$
A. $To act as a site for the light-independent reactions of photosynthesis$
B. $To serve as a 'glue' that cements the cell walls of adjacent plant cells together$
C. $To provide a channel for the movement of mRNA between cells$
D. $To store starch granules for winter survival$
10.
$Which functional group of the phospholipid molecule is responsible for the 'attraction' to water?$
A. $The non-polar fatty acid tails$
B. $The polar phosphate head$
C. $The glycerol backbone which is strictly hydrophobic$
D. $The cholesterol molecules embedded between the tails$

Download the worksheet for Biology: Life and Systems - Cell Theory and Organelles to practice offline. It includes additional chapter-level practice questions.

Human Body Systems (Digestive, Respiratory, Circulatory)

Subtopic

Human Body Systems (Digestive, Respiratory, Circulatory) under Biology: Life and Systems for Grade 8 IB.

About Topic & Revision

Preview questions (no answers)

1.
$What is the name of the two large tubes that branch off the trachea into each lung?$
A. $Capillaries$
B. $Bronchi$
C. $Esophagus$
D. $Arteries$
2.
$How does oxygen move from the lungs into the bloodstream?$
A. $By active transport$
B. $By diffusion$
C. $By peristalsis$
D. $By pumping$
3.
$Which blood vessel carries oxygenated blood from the lungs back to the heart?$
A. $Pulmonary Artery$
B. $Vena Cava$
C. $Aorta$
D. $Pulmonary Vein$
4.
$Which organ is the final part of the digestive tract where waste leaves the body?$
A. $Large Intestine$
B. $Anus$
C. $Rectum$
D. $Appendix$
5.
$In the human heart, the right and left sides are completely separated by a thick muscular wall called the septum. Based on the path of blood flow shown in the diagram, what is the primary biological advantage of this structural division?$
A. $It allows the heart to store a larger volume of blood between beats.$
B. $It prevents the mixing of oxygenated and deoxygenated blood to maintain efficiency.$
C. $It reduces the pressure of the blood before it enters the lungs.$
D. $It acts as a primary site for the exchange of gases within the heart.$
6.
$Which organ is primarily responsible for the production of protease, lipase, and amylase simultaneously?$
A. $Stomach$
B. $Pancreas$
C. $Liver$
D. $Salivary glands$
7.
$Which of the following identifies the correct order of the respiratory system structures through which air passes during inhalation?$
A. $Nose -> Larynx -> Trachea -> Bronchi -> Alveoli$
B. $Nose -> Bronchi -> Alveoli -> Trachea$
C. $Nose -> Trachea -> Lungs -> Pharynx$
D. $Nose -> Alveoli -> Bronchi -> Trachea$
8.
$What is the primary function of the pulmonary veins?$
A. $To carry oxygenated blood from the lungs to the left atrium.$
B. $To carry deoxygenated blood from the heart to the lungs.$
C. $To carry oxygenated blood from the heart to the rest of the body.$
D. $To carry deoxygenated blood from the upper body to the right atrium.$
9.
$If a person consumes a large amount of an antacid, raising the pH of their stomach to 7, which process will be most significantly inhibited?$
A. $The emulsification of fats by bile.$
B. $The breakdown of starch by salivary amylase.$
C. $The activation of pepsinogen into pepsin for protein digestion.$
D. $The absorption of water in the large intestine.$
10.
$Which of the following best explains why people with a low red blood cell count (anemia) often feel tired and short of breath?$
A. $Their blood is too thin to flow through the narrow capillaries of the brain.$
B. $They cannot produce enough carbon dioxide to trigger the breathing reflex.$
C. $Their blood has a reduced capacity to transport oxygen to tissues for aerobic respiration.$
D. $The lack of red blood cells causes the heart to stop beating effectively.$

Download the worksheet for Biology: Life and Systems - Human Body Systems (Digestive, Respiratory, Circulatory) to practice offline. It includes additional chapter-level practice questions.

Genetics and DNA Structure

Subtopic

Genetics and DNA Structure under Biology: Life and Systems for Grade 8 IB.

About Topic & Revision

Preview questions (no answers)

1.
$What is the term for a different version or form of a specific gene?$
A. $Allele$
B. $Nucleotide$
C. $Chromosome$
D. $Mutation$
2.
$What happens to the amount of DNA in a cell before it divides?$
A. $It is halved$
B. $It stays the same$
C. $It doubles$
D. $It disappears$
3.
$Which of these traits is most likely to be determined by your DNA?$
A. $Favorite food$
B. $Natural hair color$
C. $Ability to speak French$
D. $Knowledge of science$
4.
$Who are the two scientists credited with creating the first accurate 3D model of the DNA double helix?$
A. $Darwin and Wallace$
B. $Watson and Crick$
C. $Schleiden and Schwann$
D. $Hooke and Leeuwenhoek$
5.
$Which of the following is true about the genetic code?$
A. $It is different for every single species on Earth.$
B. $It is nearly universal among all living organisms.$
C. $It only applies to animals, not plants.$
D. $It changes every time a cell divides.$
6.
$What provides the energy required to link nucleotides together during DNA replication?$
A. $Sunlight$
B. $The phosphate groups themselves$
C. $The sugar molecules$
D. $The nitrogenous bases$
7.
$How many hydrogen bonds form between Cytosine and Guanine in a DNA molecule?$
A. $1$
B. $2$
C. $3$
D. $4$
8.
$Which part of the DNA molecule carries a negative charge, allowing it to migrate toward a positive electrode during gel electrophoresis?$
A. $The nitrogenous bases$
B. $The deoxyribose sugars$
C. $The phosphate groups$
D. $The hydrogen bonds$
9.
$Analyze the hierarchy of genetic material. Which list is correctly ordered from smallest to largest?$
A. $Nucleotide, Gene, DNA molecule, Chromosome, Nucleus$
B. $Gene, Nucleotide, Chromosome, DNA molecule, Nucleus$
C. $Nucleus, Chromosome, DNA molecule, Gene, Nucleotide$
D. $Nucleotide, DNA molecule, Gene, Chromosome, Nucleus$
10.
$U A C$
A. $The protein will be longer than normal.$
B. $The protein will be shorter than normal and likely non-functional.$
C. $The protein will have one amino acid changed but remain the same length.$
D. $There will be no change to the protein.$

Download the worksheet for Biology: Life and Systems - Genetics and DNA Structure to practice offline. It includes additional chapter-level practice questions.

Ecology and Interactions in Ecosystems

Subtopic

Ecology and Interactions in Ecosystems under Biology: Life and Systems for Grade 8 IB.

About Topic & Revision

Preview questions (no answers)

1.
$What happens to the waste and remains of organisms in an ecosystem?$
A. $They disappear completely$
B. $They are broken down by decomposers$
C. $They turn into energy for producers$
D. $They are only eaten by predators$
2.
$Which of the following is the most complex level of organization in ecology?$
A. $Organism$
B. $Population$
C. $Community$
D. $Ecosystem$
3.
$When two species both try to use the same limited resource, it is called:$
A. $Mutualism$
B. $Commensalism$
C. $Competition$
D. $Parasitism$
4.
$What is the term for the sum of all ecosystems on Earth?$
A. $Atmosphere$
B. $Hydrosphere$
C. $Biosphere$
D. $Lithosphere$
5.
$Which of the following is a density-dependent limiting factor?$
A. $A sudden volcanic eruption$
B. $A widespread contagious disease$
C. $An unusually cold winter$
D. $A forest fire caused by lightning$
6.
$Which type of ecological pyramid can sometimes be 'inverted' (smaller at the bottom) in specific aquatic ecosystems?$
A. $Pyramid of energy$
B. $Pyramid of numbers$
C. $Pyramid of heat$
D. $Pyramid of sunlight$
7.
$Bees collect nectar from flowers for food and, in the process, transfer pollen from one flower to another, helping the plants reproduce. This is an example of:$
A. $Mutualism$
B. $Competition$
C. $Parasitism$
D. $Predation$
8.
$Which of the following statements about 'Energy Pyramids' is always true?$
A. $They can be inverted if the producers are very large.$
B. $The highest level always contains the most energy.$
C. $They are always upright because energy is lost at each transfer.$
D. $They represent the number of individual organisms at each level.$
9.
$What kind of population growth is represented by a 'J-shaped' curve?$
A. $Logistic growth$
B. $Exponential growth$
C. $Linear growth$
D. $Negative growth$
10.
$CO_2$
A. $CO_2$
B. $CO_2$
C. $Both A and B are correct.$
D. $CO_2$

Download the worksheet for Biology: Life and Systems - Ecology and Interactions in Ecosystems to practice offline. It includes additional chapter-level practice questions.

Photosynthesis and Cellular Respiration

Subtopic

Photosynthesis and Cellular Respiration under Biology: Life and Systems for Grade 8 IB.

About Topic & Revision

Preview questions (no answers)

1.
$Which of the following is the correct word equation for photosynthesis?$
A. $\rightarrow$
B. $\rightarrow$
C. $\rightarrow$
D. $\rightarrow$
2.
$What is the function of the air spaces in the spongy mesophyll layer of a leaf?$
A. $To store extra water$
B. $To allow gases to circulate and reach the cells$
C. $To make the leaf float on water$
D. $To protect the leaf from insects$
3.
$What type of energy is light energy converted into during the process of photosynthesis?$
A. $Kinetic energy$
B. $Chemical energy$
C. $Thermal energy$
D. $Sound energy$
4.
$What happens to the rate of photosynthesis if the concentration of carbon dioxide in the air increases (assuming light and temperature are constant)?$
A. $The rate increases$
B. $The rate decreases$
C. $The rate stays the same$
D. $Photosynthesis stops completely$
5.
$Which of the following sets of factors can all act as 'limiting factors' for the rate of photosynthesis?$
A. $Light intensity, temperature, and carbon dioxide concentration.$
B. $Oxygen concentration, soil type, and plant height.$
C. $Glucose concentration, ATP levels, and nitrogen gas.$
D. $Number of consumers, wind speed, and lunar phase.$
6.
$Which molecule is known as the 'universal energy currency' of the cell?$
A. $Glucose$
B. $Starch$
C. $ATP$
D. $Chlorophyll$
7.
$In an ecosystem, what would happen if all the decomposers (like fungi and bacteria) stopped performing cellular respiration?$
A. $Oxygen levels would increase rapidly.$
B. $CO_2$
C. $Plants would be able to photosynthesize much faster.$
D. $The Sun's energy would no longer reach the Earth's surface.$
8.
$Which of the following statements best describes the relationship between the 'energy currency' of the cell and the processes of photosynthesis and respiration?$
A. $Photosynthesis creates ATP to be stored in the roots for winter$
B. $Respiration uses the chemical energy in glucose to phosphorylate ADP into ATP$
C. $ATP is the primary byproduct of photosynthesis released into the air$
D. $Glucose is the only molecule that can provide energy for cellular work$
9.
$CO_2$
A. $Glucose$
B. $ATP$
C. $A 3-carbon intermediate (PGA/3-PGA)$
D. $Chlorophyll$
10.
$CO_2$
A. $From the oxygen molecules inhaled during breathing$
B. $From the glucose molecule that was broken down during glycolysis$
C. $From the ATP molecules used to power the cycle$
D. $From the water molecules split during photosynthesis$

Download the worksheet for Biology: Life and Systems - Photosynthesis and Cellular Respiration to practice offline. It includes additional chapter-level practice questions.

Biology: Life and Systems

Cell Theory and Organelles

❓Preview questions (no answers)

Human Body Systems (Digestive, Respiratory, Circulatory)

❓Preview questions (no answers)

Genetics and DNA Structure

❓Preview questions (no answers)

Ecology and Interactions in Ecosystems

❓Preview questions (no answers)

Photosynthesis and Cellular Respiration

❓Preview questions (no answers)

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