Cell Biology Concepts

Sieve Tube Cells

• Plant sieve tube cells lack a nucleus

Ribosomes

• Ribosomes are not without a role in protein synthesis
• Ribosomes are composed of two subunits
• Ribosomes form polysomes and can attach to mRNA

Eukaryotes

• Anabaena is not a eukaryote

Chromosome Staining

• Safranin is not used for staining chromosomes

Cell Sizes

• Arrangement of cells in ascending order of size: Mycoplasma < Bacteria < Human RBCs < Ostrich eggs

Common Features of Cells

• Chromosomes are found in both prokaryotes and many eukaryotes

Fluid Mosaic Model

• Singer and Nicolson proposed the fluid mosaic model of the plasma membrane

Secretory Cells

• Rough Endoplasmic Reticulum is easily observed in a secretory cell

Tonoplast

• The tonoplast is the membrane boundary of the vacuole in plant cells

Eukaryotic Cells

• The cell wall of a eukaryotic cell is not made of peptidoglycans

Cell Membrane

• Carbohydrates are found in the cell membrane

Plastids vs Mitochondria

• Plastids contain thylakoids, but mitochondria do not

Cytoskeleton

• Intracellular transport is not a function of the cytoskeleton

Visualizing Mitochondria

• Janus Green is used to visualize mitochondria

Mitochondria and Chloroplasts

• Statement I being that Mitochondria and Cholorplasts are semi-autonomous ogranelles is correct
• Statement II being that Mitochondria and Chloroplasts contain DNA but lack protein synthesismachinery is incorrect

Bacteria Classification and Plasma Membrane

• Statement I claiming bacteria are classified due to cell envelope differences; is incorrect
• Statement II claiming the plasma membrane is selectively permeable; is correct

Bacterial Flagellum

• Statement I is that a bacterium flagellum is composed of three parts
• Statement II says it is composed of a filament, hook, and basal body is correct

Eukaryotic and Plant Cells

• Statement I saying that all eukaryotic cells are identical is incorrect
• Statement II claiming that a plant cell has centrioles, is incorrect

Algae and Plant Cell Walls

• Statement I: Algae cell walls are made of cellulose, galactans, mannans, and minerals
• Statement II: Plant cell walls are made of cellulose, hemicellulose, pectins, and proteins.

Matching

• Nucleolus - Site for ribosomal RNA synthesis
• Centriole - Organization like the cartwheel
• Leucoplasts - For storage of nutrients
• Golgi apparatus - Site of formation of glycolipid

Chloroplast DNA

• DNA in the chloroplast is circular and double stranded

Matching

• Axoneme: Cilia and flagella
• Cartwheel pattern: Centriole
• Crista: Mitochondria
• Satellite: Chromosome

Mitochondria and Chloroplast Membranes

• Statement I: Mitochondria and chloroplasts are both double membrane bound organelles is correct
• Statement II: The inner membrane of mitochondria is relatively less permeable compared to the chloroplasts, is incorrect

Endomembrane System

• Mitochondria, Chloroplasts and Peroxisomes are not part of the endomembrane system

Golgi Apparatus

• The Golgi apparatus is an important site for the formation of glycoproteins and glycolipids
• Protein is modified by ribosomes on the ER, within the Golgi apparatus

Plasma Membrane

• Movement of the components can be measured as fluidity of membrane
• D indicates the polar tail the tail of which contains saturated hydrocarbons

Contractile Vacuole

• Contractile vacuoles are important for osmoregulation

Cell Organelle

• Ribosomes are granular structures and composed of RNA and proteins, without any surrounding membrane

Centrosome and Centrioles

• For Centrosome and Centrioles the following statement is incorrect
• "Centrioles are made up of nine unevenly spaced peripheral fibrils of tubulin."

Schleiden and Schwann

• Mathias Schleiden discovered that all plant tissues are made up of cells
• Theodore Schwann discovered different types of animal cells at the same time

Fluid-Mosaic Model

• Fluidity enables the lateral movement of lipids within the overall bilayer

Plasma Membrane Importance

• One of the most important functions of the plasma memebrane is transport of molecules across it

Transport of Molecules

• Polar and hydrophobic molecules cannot pass through the lipid bilayer, so require a carrier protein to facilitate their transport across the membrane

Sodium-Potassium Pump

• The Sodium Potassium pump is an example of active transport

Transport

• Nonpolar molecules do not facilitate diffusion

Mitochondria

• Statement A saying that mitochondria are easily visible under a microscope and Statement D saying that mitochondria have two aqueous compartments are correct

Mitochondrial Membrane

• The inner mitochondrial membrane forms infoldings called cristae

Number of Mitochondria

• The number of mitochondria per cell depends on the physiological activity of the cells

Endomembrane System

• The nucleus is not a component of the endomembrane system

Packaging in the Golgi Apparatus

• Vesicular structures are produced through the process of lysosomes in the Golgi. They're filled with hydrolytic enzymes

Ribosomes

• Eukaryotes have 80S and prokaryotes have 70S ribosomes
• "S" denotes the sedimentation coefficient, an indirect measure of density & size

RNA Name

• In r-RNA, "r" stands for ribosomal

Chromosomes

• Interphase cells have chromatin. Dividing cells show structured chromosomes

Human Cell DNA

• A human cell has roughly a 2-metre thread of DNA distributed among its chromosomes. Each cell has 46 chromosomes

Cell Membrane Properties

• All types of molecules cannot easily pass through the membrane

Higher to Lower Concentrations

• Neutral solutes move across the plasma membrane from higher to lower concentration along the concentration gradient without transmembrane proteins

Statement

• Non polar molecules can not pass through non polar lipid bilayer.

Cell Wall Function

• Secretion is not a function of a cell wall

Components

• A constituent of an algal cell wall is cellulose, galactans or mannans
• Chitin is also not a constituent of an algal cell wall

Endoplasmic Reticulum Activity

• The endoplasmic reticulum helps with transport, synthesis of glycogen and lipoproteins

Steroidal Synthesis

• Steroidal hormones are synthesized by the Smooth Endoplasmic Reticulum

Golgi Complex Protein Receival

• The Golgi Complex receives modified proteins from the Rough Endoplasmic Reticulum at the cis face

Plastids

• Classification of plastids into the chloroplast, chromoplast, and leucoplast categories is based on pigments

Cilia and Flagella

• Flagella are responsible for the movement of surrounding fluid

Core Name

• Plasma membrane covers the central core of flagella and cilia and it is known as an axoneme

Classification

• The classification of chromosomes is based on the position of the centromere

Centromere Position

• A chromosome with a centromere that is slightly away from the center is submetacentric

Columns

• Plasma membrane is a barrier between cytoplasm and the outside
• Centrioles help in cell division
• Ribosomes synthesizes protein
• Plastids aren't not present in animal cells
• Lysomes is Rich in hrdolytic enzymes

Functions

• The following IS NOT a function of a cell wall, it doesn't help in cell recognition

Organisms

• Unicellular organisms have independent existence; All cells do arise from pre-existing cells and cytoplasm is the main part where activities occur

Vacuoles

• Tonoplast does not facilitate transport of ions against the concentration gradient into cytoplasm

Cell Organelle

• A cell organelle that contains hudrolytic enzymes is lysosomes

Carbohydrates

• Mitochondria are responsible for extracting energy from carbohydrates to form ATP

Nucleolus facts

• A fact about the Nucleolus is that it is a site for active ribosomal RNA synthesis

Golgi Complex

• The Golgi Complex participates in the formation of secretory vesicles

ER Facts

• Phospholipid Synthesis DOES NOT in the Rough Endoplasmic Reticulum

Submetacentric

• The shorter and longer arms of a submetacentric chromosome are refereed to as, p-arm and q-arm respectively

Organelles with DNA

• Mitochondria and Lysosomes do not contain DNA

Lysosome processes

• Lysosomes are formed by the process of packaging in the endoplasmic reticulum

Cellula-e

• Rudolf Virchow propounded that the concept of omnis cellula-e cellula

Mitochondria's Membrane

• Enzymes of electron transport are not embedded in the outer membrane in mitochondria

Secretory Cells

• Endoplasmic Reticulum have the highest number of cell organelles

Non-membranous structures

• Non-membranous structures in the nucleolus are the site for active synthesis of rRNA

Column Match

• For Golgi apparatus
  • The functions are, for the formation of glycoproteins and glycolipids

Eukaryotic Cells

• The important site of the formation of glycoproteins and glycolipids in eukaryotic cells is the golgi bodies

rRNA Biosynthesis

• The biosynthesis of ribosomal RNA occurs in the nucleolus

Cell components

• Smooth Endoplasmic Reticulum for Lipid synthesis
• Rough Endoplasmic Reticulum for Protein synthesis
• Golgi complex for Glycosylation
• Centriole for Spindle formation

Centromere

• the Centromere when situation in the middle of two equal arms of chromosomes is referred as Metacentric

Lists one and two match

• The correct match is Thylakoids to the flattened membranous sacs in stroma of plastids

Sieve elements

• Conspicuous nuclease with usual cytoplasmic organelles DOES NOT occurs in mature sieve tube elements

Membranes

• Mitochondria and Ribosomes & Lysosome DOES NOT occurs in endomembrane system

Columns

• (a) Endoplasmic reticulum - (v) Stack of cisternae
• (b) Sphaerosomes - (iii) stores oil
• (c) Dictyosomes - (i) Synthesis and storage of lipids
• (d) Peroxisomes - (vii) Photorespiration
• (e) Elaioplasts- (ii) Detoxification of drugs

Lamella

• The middle lamella is a layer which holds the different neighbouring cells together

Short to very long

• Acrocentric chromosome have "Centromere close situated close to the end forming one extremely short and one very long" arm

ER

• ER contains Ribosomes and are often the sites for Lipid Synethisis, so the RER must have ribosomes attacthed to it

1 Micron Filters

• Mycoplasmas are very small, so they can pass through a 1 micron filter. However, they dont have a cell wall

Endosystem

• In fact, Mitochondria and chloroplasts are not parts of the Endosystem/Endomembrane system

Column Selections

• Chromoplasts relates to carotene best as it is the pigment.

Lysosomes with PH

• It they are increased, then hydrolytic enzymes would become inactive