Edexcel 9-1 GCSE Biology Topic 1 Cells Microscopes and Enzymes Questions With 100% Verified Correct Answers.

eyepiece lens - correct answer The part of the microscope you look down. magnification - correct answer How much bigger something appears compared with its actual size. objective lens - correct answer The part of the microscope that is closest to the specimen. resolution - correct answer Smallest change that can be measured by an instrument. For example, in a microscope it is the smallest distance between two points that can be seen as two points and not blurred into one point. stain - correct answer A dye used to colour parts of a cell to make them easier to see. aerobic respiration - correct answer A type of respiration in which oxygen is used to release energy from substances, such as glucose. cell (surface) membrane - correct answer The membrane that controls what goes into and out of a cell. It is often called the cell surface membrane because eukaryotic cells contain other structures with membranes. cell sap - correct answer Liquid found in the permanent vacuole in a plant cell. cell wall - correct answer A tough layer of material around some cells, which is used for protection and support. It is stiff and made of cellulose in plant cells. Bacteria have a flexible cell wall. chlorophyll - correct answer The green substance found inside chloroplasts. It traps energy transferred by light. chloroplasts - correct answer A green disc containing chlorophyll, found in plant cells. Where the plant makes glucose, using photosynthesis. chromosome - correct answer A structure found in the nuclei of cells. Each chromosome contains one enormously long DNA molecule. cytoplasm - correct answer The watery jelly inside a cell where the cell's activities take place. eukaryotic - correct answer A cell with a nucleus is eukaryotic. Organisms that have cells like this are also said to be eukaryotic. field of view - correct answer The circle of light you see looking down a microscope. mitochondrion - correct answer A sub-cellular structure (organelle) in the cytoplasm of eukaryotic cells, where aerobic respiration occurs. Plural is mitochondria. nucleus - correct answer The 'control centre' of a eukaryotic cell. ribosome - correct answer Tiny sub-cellular structure that makes proteins. scale bar - correct answer A line drawn on a magnified image that shows a certain distance at that magnification. scientific paper - correct answer An article written by scientists and published in a science magazine called a journal. It is like an investigation report but usually shows the results and conclusions drawn from many experiments. vacuole - correct answer A storage space in cells. Plant cells have a large, permanent vacuole that helps to keep them rigid. acrosome - correct answer A small vacuole in the tip of the head of a sperm cell, which contains enzymes. adaptation - correct answer The features that something has to enable it to do a certain function (job). adapted - correct answer If something has adaptations for a certain function (job), it is said to be adapted to that function. ciliated epithelial cell - correct answer A cell that lines certain tubes in the body and has cilia on its surface. cilium - correct answer A small hair-like structure on the surface of some cells. Plural is cilia. digestion - correct answer A process that breaks molecules into smaller, more soluble substances. diploid - correct answer Describes a cell that has two sets of chromosomes. egg cell - correct answer The female gamete (sex cell). embryo - correct answer The tiny new life that grows by cell division from a fertilised egg cell (zygote). enzyme - correct answer A substance that can speed up some processes in living things (e.g. breaking down molecules). epithelial cell - correct answer A cell found on the surfaces of parts of the body. fertilisation - correct answer Fusing of a male gamete with a female gamete. gamete - correct answer A cell used for sexual reproduction. haploid - correct answer Describes a cell that has one set of chromosomes. microvillus - correct answer A fold on the surface of a villus cell. These folds increase the surface area so that digested food is absorbed more quickly. Plural is microvilli. oviduct - correct answer A tube that carries egg cells from the ovaries to the uterus in females. Fertilisation happens here. specialised cell - correct answer A cell that is adapted for a certain specific function (job). sperm cell - correct answer The male gamete (sex cell). chromosomal DNA - correct answer DNA found in chromosomes but the term is often used to describe the large loop of DNA found in bacteria. DNA - correct answer A substance that contains genetic information. Short for deoxyribonucleic acid. flagellum - correct answer A tail-like structure that rotates, allowing a unicellular organism to move. Plural is flagella. plasmid - correct answer A small loop of DNA found in the cytoplasm of bacteria. plasmid DNA - correct answer DNA found in plasmids. prokaryotic - correct answer A cell with no nucleus is prokaryotic. Organisms such as bacteria, which have cells like this, are also said to be prokaryotic. standard form - correct answer A very large or very small number written as a number between 1 and 10 multiplied by a power of 10. Example: A × 10n where A is between 1 and 10 and n is the power of 10 biological catalyst - correct answer A substance found in living organisms that speeds up reactions (an enzyme). catalyst - correct answer A substance that speeds up the rate of a reaction, without itself being used up. digest - correct answer To break down large molecules into smaller subunits, particularly in the digestive system. monomer - correct answer A small molecule that can join with other molecules like itself to form a polymer. polymer - correct answer A substance made up of very long molecules containing repeating groups of atoms. (Formed by joining monomer molecules together.) product - correct answer A substance formed in a reaction. substrate - correct answer A substance that is changed during a reaction. synthesis - correct answer To build a large molecule from smaller subunits.