5.fundamental unit of life Flashcards
who discover cells
rrobert hooke
cell theorry was first proposed by
Schleiden and Schwann.
who discovered the nucleus
robert brown
What was the primary contribution of Robert Hooke in the field of cell biology?
He observed and described the first cells in a cork slice.
Which scientist is credited with the discovery of free-living cells in pond water?
Antonie van Leeuwenhoek
The term ‘protoplasm’ was coined by which of the following scientists?
(a) Schleiden
(b) Schwann
(c) Purkinje
(d) Leeuwenhoek
(c) Purkinje
The cell theory states that:
The cell theory states that:
Which of the following organisms is an example of a unicellular organism?
(a) Mushroom
(b) Paramecium
(c) Oak tree
(d) Human
(b) Paramecium
The discovery of which tool in 1940 greatly advanced the study of cell structure?
(a) Light microscope
(b) Optical lens
(c) Scanning electron microscope
(d) Transmission electron microscope
(d) Transmission electron microscope
What is the primary function of the nucleus discovered by Robert Brown?
(a) Energy production
(b) Genetic material storage and regulation of cell activities
(c) Synthesis of proteins
(d) Photosynthesis in plant cells
(b) Genetic material storage and regulation of cell activities
What determines the shape and size of a cell?
(a) The age of the organism
(b) The specific function it performs
(c) The type of nutrients it receives
(d) The presence of organelles
(b) The specific function it performs
Which of the following cells has a changing shape?
(a) Nerve cells
(b) Muscle cells
(c) Amoeba
(d) Red blood cells
(c) Amoeba
What is the primary function of the plasma membrane?
(a) To produce energy
(b) To store genetic material
What is the primary function of the plasma membrane?
(a) To produce energy
(b) To store genetic material
(c) To separate the cell contents from the external environment
(d) To aid in cell division
(d) To aid in cell division
What is the primary function of the plasma membrane?
(a) To produce energy
(b) To store genetic material
(c) To separate the cell contents from the external environment
(d) To aid in cell division
What type of membrane is the plasma membrane classified as?
(a) Permeable membrane
(b) Selectively permeable membrane
(c) Impermeable membrane
(d) Semi-permeable membrane
(b) Selectively permeable membrane
How do substances like oxygen and carbon dioxide move across the plasma membrane?
(a) Active transport
(b) Osmosis
(c) Diffusion
(d) Filtration
(c) Diffusion
What is the movement of water molecules through a selectively permeable membrane called?
(a) Diffusion
(b) Osmosis
(c) Active transport
(d) Facilitated diffusion
(b) Osmosis
When carbon dioxide accumulates in a cell, it moves out of the cell due to which process?
(a) Active transport
(b) Osmosis
(c) Diffusion
(d) Endocytosis
(c) Diffusion
Which of the following components in a cell performs specific functions such as waste removal and material synthesis?
(a) Cell membrane
(b) Organelles
(c) Cytoplasm
(d) Nucleus
(b) Organelles
What is the primary role of the nucleus in a cell?
(a) Energy production
(b) Genetic material storage
(c) Waste removal
(d) Protein synthesis
(b) Genetic material storage
What is osmosis?
The net diffusion of water across a selectively permeable membrane.
What type of solution has a higher water concentration than the cell?
(a) Isotonic solution
(b) Hypertonic solution
(c) Hypotonic solution
(d) Saturated solution
(c) Hypotonic solution
What will happen to an animal cell placed in a hypotonic solution?
(a) The cell will shrink.
(b) The cell will swell up.
(c) The cell will stay the same size.
(d) The cell will burst and die
(b) The cell will swell up.
In an isotonic solution, what happens to the movement of water across the cell membrane?
There is no net movement of water.
What happens to a cell placed in a hypertonic solution?
) The cell will lose water and shrink.
Which of the following describes the movement of water in a hypotonic solution?
More water enters the cell than leaves.
What role does a selectively permeable membrane play in osmosis?
It allows water to pass while controlling the movement of solutes.
When an animal cell is placed in a hypertonic solution, it undergoes a process called:
(a) Cytolysis
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(c) Osmotic pressure
(d) Osmotic balance
(b) Plasmolysis
In a solution with lower solute concentration compared to the cell, water moves:
(a) Out of the cell
(b) Into the cell
(c) In and out equally
(d) Not at all
(b) Into the cell
Which of the following statements is true about osmosis?
(a) It is a form of active transport.
(b) It requires energy input from the cell.
(c) It is a special case of diffusion.
(c) It is a special case of diffusion
What is the main composition of the plant cell wall?
Cellulose.
How do cell walls benefit plant cells in hypotonic environments?
They provide structural support and prevent bursting.
Question: What structure covers the nucleus?
(a) Plasma membrane
(b) Cell wall
(c) Nuclear membrane
(d) Cytoplasm
Nuclear membrane.
Which type of cells lack a nuclear membrane?
Prokaryotic cells.
What is the undefined nuclear region in prokaryotic cells called?
(a) Chromatin
(b) Nucleus
(c) Nucleoid
(d) Nucleolus
(c) Nucleoid
What are chromosomes composed of
DNA and protein.
What phenomenon occurs when a living plant cell loses water through osmosis?
Plasmolysis.
Which type of cells are capable of absorbing water by osmosis?
Only living cells.
What are functional segments of DNA called?
genes
What is one role of the nucleus in a cell?
To direct chemical activities and cellular reproduction
Which type of cells have a defined nuclear membrane?
eukaryotic cells
What distinguishes eukaryotic cells from prokaryotic cells?
Eukaryotic cells contain membrane-enclosed organelles and a nuclear membrane.
What are cell organelles?
They are specialized structures within a cell that perform specific functions.
: In prokaryotic cells, what is absent besides a defined nuclear region?
Membrane-bound organelles.
Question: What is the primary structure of the endoplasmic reticulum (ER)?
(a) A solid structure
(b) A large network of membrane-bound tubes and sheets
(c) A spherical organelle
(d) A rigid cell wall
(b) A large network of membrane-bound tubes and sheets
Which type of endoplasmic reticulum has ribosomes attached to its surface?
) Rough endoplasmic reticulum (RER).
What is the main function of ribosomes attached to the rough endoplasmic
Protein manufacture.
hat does the smooth endoplasmic reticulum (SER) primarily help to synthesize?
(c) Lipids
Question: What is the process called when proteins and lipids help in building the cell membrane?
(a) Membrane degradation
(b) Membrane transport
(c) Membrane biogenesis
(d) Membrane fusion
(c) Membrane biogenesis
Question: In prokaryotic cells, which of the following is absent?
(a) Ribosomes
(b) Endoplasmic reticulum
(c) Plasma membrane
(d) Cytoplasm
(b) Endoplasmic reticulum
Question: The smooth endoplasmic reticulum (SER) is primarily involved in which of the following processes?
(a) Photosynthesis
(b) Energy production
(c) Lipid metabolism
(d) Protein folding
(c) Lipid metabolism
In liver cells of vertebrates, what crucial role does the smooth endoplasmic reticulum (SER) play?
(a) Protein synthesis
(b) Lipid storage
(c) Detoxification of poisons and drugs
(d) Energy production
) Detoxification of poisons and drugs
: Which part of the endoplasmic reticulum (ER) is involved in detoxifying harmful substances in the cell?
(a) Rough endoplasmic reticulum (RER)
: Which part of the endoplasmic reticulum (ER) is involved in detoxifying harmful substances in the cell?
(a) Rough endoplasmic reticulum (RER)
(b) Smooth endoplasmic reticulum (SER)
(c) Golgi apparatus
(d) Ribosome
(c) Golgi apparatus
(d) Ribosome
: Which part of the endoplasmic reticulum (ER) is involved in detoxifying harmful substances in the cell?
(a) Rough endoplasmic reticulum (RER)
(b) Smooth endoplasmic reticulum (SER)
(c) Golgi apparatus
(d) Ribosome
In addition to serving as transport channels, what is another significant function of the ER
acilitating biochemical reactions.
Who first described the Golgi apparatus?
) Camillo Golgi
The Golgi apparatus is primarily involved in which of the following functions?
Storage, modification, and packaging of products.
Question: How does the Golgi apparatus relate to the endoplasmic reticulum (ER)?
It often has connections with the membranes of the ER.
What happens to materials synthesized near the ER?
They are packaged and dispatched through the Golgi apparatus.
n addition to packaging products, what other role does the Golgi apparatus play?i
Formation of lysosomes.
Question: Which of the following processes can occur in the Golgi apparatus?
(a) Synthesis of ATP
(b) Formation of complex sugars from simple sugars
(c) Cellular respiration
(d) Genetic transcription
(b) Formation of complex sugars from simple sugars
Question: The stacks of membranes in the Golgi apparatus are referred to as:
(a) Vesicles
(b) Cisterns
(c) Tubules
(d) Golgi bodies
(b) Cisterns
Question: What are lysosomes primarily composed of?
(a) Protein fibers
(b) Membrane-bound sacs filled with digestive enzymes
(c) Carbohydrate granules
(d) Lipid droplets
(b) Membrane-bound sacs filled with digestive enzymes
Question: Where are the enzymes found in lysosomes made?
(a) Golgi apparatus
(b) Smooth endoplasmic reticulum (SER)
(c) Rough endoplasmic reticulum (RER)
(d) Nucleus
Rough endoplasmic reticulum (RER)
What is the main function of lysosomes in the cell?
(a) Protein synthesis
(b) Energy production
(c) Waste disposal system
(d) DNA replication
(c) Waste disposal system
Lysosomes contain enzymes that are capable of breaking down which type of material?
Organic material
Question: Which cell organelle is responsible for breaking complex substances into simpler substances within the cell?
(a) Mitochondria
(b) Golgi apparatus
(c) Lysosomes
(d) Ribosomes
(c) Lysosomes
How many membrane coverings do mitochondria have?
2
question: What is the characteristic of the outer membrane of mitochondria?
(a) It is smooth
(b) It is porous
(c) It has ribosomes attached
(d) It is thick
(b) It is porous
Question: What is the significance of the folds in the inner membrane of mitochondria?
(a) They store DNA
(b) They increase surface area for ATP-generating chemical reactions
(c) They store waste materials
(d) They transport water
(b) They increase surface area for ATP-generating chemical reactions
What is the main molecule produced by mitochondria that provides energy to the cell?
ATP (Adenosine triphosphate).
Question: Why are mitochondria considered unique organelles?
(a) They can divide independently of the cell
(b) They have their own DNA and ribosomes
(c) They are only present in plant cells
(d) They cannot generate energy
(b) They have their own DNA and ribosomes
What ability do mitochondria have due to their own DNA and ribosomes?
They can make some of their own proteins.
Plastids are found in which type of cells?
Plant cells.
Question: What are the two main types of plastids?
(a) Nucleoplasts and vacuoplasts
(b) Chromoplasts and leucoplasts
(c) Chloroplasts and mitochondria
(d) Lysosomes and peroxisomes
(b) Chromoplasts and leucoplasts
Question: Which pigments do chloroplasts contain besides chlorophyll?
(a) Blue or red pigments
(b) Yellow or orange pigments
(c) Black or white pigments
(d) Pink or purple pigments
(b) Yellow or orange pigments
Question: Leucoplasts primarily store which materials?
(a) Sugars and fats
(b) Starch, oils, and protein granules
(c) Vitamins and minerals
(d) Water and waste
(b) Starch, oils, and protein granules
How are chloroplasts similar to mitochondria?
They both have their own DNA and ribosomes.
What is the material inside the chloroplasts where membrane layers are embedded called?
(a) Matrix
(b) Stroma
(c) Cytoplasm
(d) Nucleoplasm
(b) Stroma
What is the main function of leucoplasts in plant cells?
Storage of starch, oils, and proteins.
Question: What is the primary function of vacuoles in cells?
Storage of solid or liquid contents.
How do vacuoles differ in size between plant and animal cells?
They are larger in plant cells.
: What types of substances are commonly stored in plant cell vacuoles?
(a) Water only
(b) Lipids and fats
(c) Amino acids, sugars, organic acids, and proteins
(d) Minerals and salts
(c) Amino acids, sugars, organic acids, and proteins
Question: What percentage of the cell volume can the central vacuole occupy in some plant cells?
(a) 10-20%
(b) 30-40%
(c) 50-90%
(d) 100%
(c) 50-90%
Which of the following processes is responsible for the formation of most cells for growth in organisms?
A) Meiosis
B) Photosynthesis
C) Mitosis
D) Respiration
Mitosis
During mitosis, how many daughter cells are formed from a single mother cell?
A) One
B) Two
C) Three
D) Four
B) Two
What is the chromosome number in daughter cells compared to the mother cell after mitosis?
A) Half the number
B) Double the number
C) The same number
D) Triple the number
C) The same number
: Which type of cell division is involved in the formation of gametes in reproductive organs?
A) Mitosis
B) Binary fission
C) Budding
D) Meiosis
D) Meiosis
What happens to the chromosome number in daughter cells produced by meiosis?
A) It doubles
B) It remains the same
C) It reduces to half
D) It triples
C) It reduces to half
: How many new cells are produced when a cell divides by meiosis?
A) Two
B) Three
C) Four
D) Eight
C) Four
: Which of the following structures is present in plant cells but not in animal cells?
A) Nucleus
B) Cell membrane
C) Cell wall
D) Mitochondria
C) Cell wall
: Both plant and animal cells have a central vacuole. true /false
False (Plant cells typically have a large central vacuole, while animal cells may have smaller, multiple vacuoles.)
(True/False)
Question: Animal cells have centrioles, which are usually not present in plant cells.
True
Centrioles are paired barrel-shaped organelles located in the cytoplasm of animal cells near the nuclear envelope
(True/False)
Question: The cell membrane is present in both plant and animal cells.
true
Which of the following organelles is responsible for providing structural support to plant cells?
cell wall
Which type of cell typically has a cell wall made of peptidoglycan?
A) Eukaryotic animal cells
B) Eukaryotic plant cells
C) Prokaryotic bacterial cells
D) Eukaryotic fungal cells
Prokaryotic bacterial cells
Which of the following is a characteristic feature of eukaryotic cells?
A) Circular DNA
B) No nucleus
C) Linear DNA
D) No ribosomes
Linear DNA
In which of the following cells are mitochondria absent?
A) Plant cells
B) Animal cells
C) Fungal cells
D) Prokaryotic cells
D) Prokaryotic cells
Which of the following structures is commonly found in eukaryotic cells but not in prokaryotic cells?
A) Ribosomes
B) Cell membrane
C) Endoplasmic reticulum
D) Cytoplasm
C) Endoplasmic reticulum
the key features that eukaryotic cells have but prokaryotic cells lack:
Membrane-bound nucleus
Mitochondria
Endoplasmic reticulum (rough and smooth)
Golgi apparatus
Lysosomes
Chloroplasts (in plant cells)
Large central vacuoles (in plant cells)
Cytoskeleton (microtubules, actin filaments, intermediate filaments)
Linear DNA organized into chromosomes
Mitotic division
Complex flagella and cilia
