Topic 1: Key Concepts in Biology Flashcards
Ciliated epithelial cell
Ciliated epithelial cells are specialized types of epithelial cells that line surfaces in the respiratory tract and uterus, equipped with cilia for moving mucus and other substances.
Cilia
Cilia are hair-like structures found on the surface of certain epithelial cells, which help in wafting substances across the tissue in one direction.
Chromosome
A chromosome is a long, coiled molecule of DNA that carries genetic information in the form of genes, essential for heredity and cellular function.
Chloroplast
Chloroplasts are organelles found in plant cells where photosynthesis occurs, converting light energy into chemical energy stored in glucose.
Cell wall
The cell wall is the outer layer composed primarily of cellulose that provides structural strength and support to plant cells.
Cell
A cell is the basic structural and functional unit of all living organisms, serving as the building block of life.
Carbohydrate
A carbohydrate is a large molecule that is synthesized from simple sugars, serving essential functions such as energy storage and structural support in organisms.
Carbohydrases
Carbohydrases are enzymes that catalyze the breakdown of carbohydrates into simpler sugars, playing a key role in digestion.
Calorimetry
Calorimetry is a method used to measure the heat transfer associated with a chemical reaction, providing insights into energy changes during the reaction.
Biuret test
The Biuret test is a chemical test that indicates the presence of proteins, resulting in a purple color when a protein-containing solution is treated with the reagent
Benedict’s test
The Benedict’s test is a chemical test used to identify reducing sugars, producing a color change that indicates the amount of reducing sugar present in a solution.
Active transport
Active transport is the movement of substances from an area of low concentration to an area of high concentration across a membrane, requiring energy input from cellular respiration to overcome the concentration gradient.
Active site
The active site refers to the specific region on an enzyme where the substrate binds, allowing the biochemical reaction to occur.
Acrosome
The acrosome is the organelle at the tip of a sperm cell that contains enzymes necessary for digesting the egg cell membrane to facilitate fertilization.
Millimetre (mm)
A unit of length equal to one thousandth of a metre, often used in various scientific measurements.
Micrometre (μm)
A unit of length equal to one millionth of a metre, commonly used to measure cells and microorganisms.
Magnification
The process of enlarging an image, calculated using the formula: image size = magnification × real size.
Lock key hypothesis
A theory suggesting that substrates must have the correct shape to fit into the active site of an enzyme, similar to a key fitting a lock.
Lipid
A large biological molecule synthesized from fatty acids and glycerol, commonly involved in energy storage and cellular structure.
Lipases
Enzymes that catalyze the breakdown of lipids into fatty acids and glycerol.
Light microscope
A type of microscope that uses a series of lenses to magnify specimens using visible light, providing lower magnification and resolution compared to electron microscopes.
Iodine test
A chemical test that produces a blue/black color when iodine solution is added to a sample containing starch.
Haploid cell
A cell that contains a single copy of each chromosome, representing half the number of chromosomes typical in gametes.
Flagella
Long, hair-like structures found in certain bacterial cells used for movement.
Eukaryotic cell
A type of cell found in plants and animals characterized by the presence of a nucleus and membrane-bound organelles.
Enzyme
A biological catalyst that increases the rate of chemical reactions in living organisms.
Emulsion test
A chemical test that produces a cloudy emulsion to detect the presence of lipids in a sample.
Electron microscope
A type of microscope that uses a beam of electrons and magnets to focus and produce highly magnified images of specimens with better resolution than light microscopes.
Egg cell
A specialized female gamete involved in reproduction, which carries genetic material from the female parent.
Diploid cell
A cell that contains two copies of each chromosome, representing a full set of chromosomes typical in somatic cells.
Diffusion
The net movement of particles from an area of higher concentration to an area of lower concentration, moving down the concentration gradient.
Denaturation
A permanent alteration in the shape of an enzyme caused by extreme pH or high temperatures, affecting its active site and preventing substrate binding.
Concentration gradient
The difference in concentration between two areas, which drives the movement of substances during processes like diffusion.
What is a vacuole?
An organelle found in plant cells that stores cell sap, providing structural support and regulating turgor pressure. Vacuoles play a crucial role in maintaining cell rigidity and storage of nutrients.
What is a sperm cell?
A specialized male gamete involved in reproduction, characterized by its mobility and genetic contribution to the offspring. Sperm cells are essential for fertilization in sexual reproduction.
Define specificity in enzymatic reactions.
The ability of an enzyme to catalyze a particular reaction; often determined by the fit of the substrate in the enzyme’s active site. Specificity is critical for the proper functioning of metabolic pathways.
What is specificity in enzymes?
The ability of an enzyme to catalyze a particular reaction; often determined by the fit of the substrate in the enzyme’s active site.
What is a specialised cell?
A cell that has undergone differentiation to perform a specific function within an organism, exhibiting unique structural features.
What are ribosomes?
Sub-cellular structures responsible for protein synthesis, translating messenger RNA into polypeptide chains.
What is resolution?
The smallest distance between two distinguishable points or objects; crucial in microscopy and imaging techniques.
What is a protein?
A large biological macromolecule composed of one or more chains of amino acids, essential for various cellular functions.
What is the rate of reaction?
The speed at which reactants are converted into products in a chemical reaction, often expressed in concentration change per unit time.
What are proteases?
Enzymes that catalyze the breakdown of proteins into amino acids, playing crucial roles in digestion and metabolism.
What is a prokaryotic cell?
A type of cell characteristic of bacteria, which lacks a membrane-bound nucleus and organelles.
What is a plasmid?
A circular DNA molecule found in the cytoplasm of prokaryotic cells, often used in genetic engineering.
What is a picometre?
A quantitative unit of length. One picometre is equal to ×10⁻¹² metres.
How many metres are in one picometre?
One picometre is equal to ×10⁻¹² metres.
