Cell: The Unit of Life

A few chromosomes have non-staining secondary constrictions at a constant location. This gives the appearance of a small fragment called the:

A chromosome where the centromere is slightly away from the middle, resulting in one shorter arm and one longer arm, is known as:

A chromosome with the centromere exactly in the middle, forming two equal arms, is called:

Every chromosome essentially has a primary constriction called the centromere, on the sides of which disc-shaped structures are present called:

The plasma membrane is selectively permeable. Based on the biochemical nature of the lipid bilayer and the provided diagram, how do polar molecules (Substance B) cross the membrane, given that they cannot pass through the non-polar tails?

Small bristle-like fibers sprouting out of the bacterial cell that help in attachment to rocks in streams or to host tissues are called:

Microbodies are minute membrane-bound vesicles that contain various enzymes. They are present in:

What happens to the sedimentation coefficient ($S$) of a ribosome if the concentration of $Mg^{2+}$ ions falls significantly below 0.001M?

How many doublets and singlets of microtubules are present in the axoneme of a eukaryotic flagellum respectively?

A cell organelle 'X' is involved in the synthesis of lysosomes and is also the site where acrosome of sperm is formed. Identify 'X'.

The non-polar tail of a phospholipid molecule is made up of:

Proteins that are totally buried in the membrane are called:

The cell wall is a non-living, rigid structure that forms an outer covering for the plasma membrane of:

Which of the following processes is crucial for the formation of intercellular junctions?

The 'Fluid Mosaic Model' proposed by Singer and Nicolson describes the plasma membrane as a quasifluid structure. This property is not only important for the lateral movement of proteins but also facilitates several other dynamic cellular processes. Based on the diagram and your knowledge of the Grade 11 Biology curriculum, which set of activities is primarily enabled by membrane fluidity?

In eukaryotic cells, the plasma membrane is mainly composed of lipids called phosphoglycerides. What is the characteristic feature of these lipids?

Identify the incorrect statement about the cell wall.

Which of the following is a function of the cell wall in both plants and bacteria?

The lipid molecules in the plasma membrane are arranged with their heads towards the outer sides and tails towards the inner part. This arrangement ensures that:

The primary cell wall of a young plant cell is dynamic. As the cell matures, the primary wall:

The Golgi apparatus consists of many flat, disc-shaped sacs called:

Which of the following is the site of the 'dark reaction' or carbon fixation in photosynthesis?

The flat membranous sacs present in the stroma of the chloroplast are:

Which of the following is common to both mitochondria and chloroplasts?

The cytoplasm of eukaryotic cells contains several proteinaceous structures that help maintain cell shape and aid in motility. Collectively, these are called:

In a plant cell, as the cell matures, where is the secondary cell wall typically deposited?

Lysosomes are considered part of the endomembrane system. Which organelle is primarily responsible for their formation?

Within the thylakoid membrane, where are the enzymes of the ATP synthase complex ($CF_0-CF_1$) located in relation to the stroma?

The ribosome is often referred to as a 'protein factory'. Which of the following is the specific site where the nascent polypeptide chain exits the ribosome?

In the cell wall, the 'Middle Lamella' is primarily composed of:

Which of the following is true about the nucleolus?

Which of the following is a function of the basal body?

What is the charge of histone proteins which helps them bind to DNA?

Centrioles are found in the cells of:

During cell division, the network of chromatin condenses to form distinct structures called:

Which of the following is correct regarding the telocentric chromosome?

The small amount of RNA present in the chromatin is primarily:

In a nucleosome, how many base pairs of DNA are typically wrapped around the histone octamer?

The 'central hub' of a centriole is:

Which type of chromosome has the centromere at the very tip?

Which organelle helps in the detoxification of drugs in the liver?

The enzymes of the lysosome are produced by:

The RER is continuous with the outer membrane of the:

Which of the following statements about the endomembrane system is TRUE?

In various protists like Amoeba, the endomembrane system forms specialized vacuoles to handle different physiological needs. Based on the functions provided in the diagram, identify the vacuole types V1 and V2.

The Endoplasmic Reticulum (ER) divides the intracellular space into two distinct environments. According to the structural organization shown in the diagram, in which compartment are the ribosomes located in a Rough ER?

The endomembrane system functions through the highly coordinated movement of materials. Based on the functional branching shown in the diagram, what are the most likely contents of the vesicles following Path A and Path B?

What is the primary function of the 'Food Vacuole' in organisms like Paramecium?

During O-linked glycosylation, sugars are attached to the hydroxyl group of which amino acid residues?

Which of the following statements about the ER is INCORRECT?

Which plastid is responsible for trapping light energy for photosynthesis?

Plastids divide by a process similar to:

The enzyme RuBisCO, essential for photosynthesis, is located in the:

Ribbon-shaped chloroplasts are characteristic of:

Plastids are easily observed under the microscope because:

The size of chloroplasts in different plant species is generally:

If a plant is deprived of light for a long period, its chloroplasts may lose chlorophyll and internal organization, becoming:

Plastid differentiation is a highly dynamic and regulated process. During leaf senescence, the chloroplast undergoes a dismantling of its thylakoid system, and the liberated lipids are sequestered into prominent 'plastoglobuli'. This results in the formation of a specific plastid type, shown as 'Organelle X' in the diagram, which can occasionally revert to a functional chloroplast during the 'regreening' process. Identify 'Organelle X'.

Which of the following is the most abundant protein in the chloroplast stroma, and arguably on Earth?

What is the significance of the chloroplast being a 'semi-autonomous' organelle?

The number of microtubules in the central part of a basal body is:

Prokaryotic flagella are made of the protein:

The two central microtubules in the axoneme are ________ each other.

Which of these is absent in the $9+2$ axoneme structure?

What happens to the $9+2$ arrangement at the very tip of the cilium?

Radial spokes are made of:

The basal body of a eukaryotic flagellum is structurally similar to:

Which statement accurately describes the 'Recovery Stroke' of a cilium?

What determines the plane of ciliary beating?

Which of the following is true for the 'central singlets' of the axoneme?

Each microtubule in a centriole triplet is made of how many protofilaments?

The formation of the spindle apparatus is essential for:

Centrioles are found in:

In the '9+0' pattern, what does '0' represent?

In the structural 'cartwheel' organization of a centriole, the internal components are arranged in a specific spatial hierarchy. Based on the provided flowchart representing the cross-sectional connectivity, what is the identity and primary role of 'Component K'?

The number of protofilaments typically found in the B and C tubules of a centriolar triplet is:

In the absence of centrioles, as seen in higher plants, the spindle is described as:

The connection between the two centrioles in a pair before $S$-phase is maintained by:

What is the consequence of 'over-expression' of Plk4 in a human cell?

In the 'triplet' microtubule, which tubule is considered 'complete' in terms of protofilaments?

Which organelle is NOT involved in the $C_2$ cycle (Photorespiration)?

Are microbodies found in the cells of fungi?

The primary substrate for peroxisomal oxidation is usually:

What type of enzymes are found inside microbodies?

An unknown organelle 'X' is isolated from a eukaryotic cell. Based on the functional and structural characteristics mapped in the diagram below, identify the organelle.

In the metabolic pathway shown below, which occurs during the germination of oily seeds such as castor, identify the organelle labeled 'G' and its correct structural description.

Compared to mitochondria, peroxisomes lack which of the following features?

Which of the following serves as the primary electron acceptor for the first enzyme (Acyl-CoA oxidase) in the peroxisomal $\beta$-oxidation pathway?

In animal cells, peroxisomes are particularly abundant in which of the following organs due to their role in detoxification?

The matrix of a microbody is generally described as being: