Biology Flashcards CELLS PDF

What is the cell membrane made up of? Phospholipids bilayer, proteins and cholesterol. What does cell membrane do? The cell membrane has a fluid semi-permeable barrier against harmful mutations and is used as a getaway for desired materials. What is the purpose of the cytoplasm? Cytoplasm is a jel...

What is the cell membrane made up of? Phospholipids bilayer, proteins and cholesterol. What does cell membrane do? The cell membrane has a fluid semi-permeable barrier against harmful mutations and is used as a getaway for desired materials. What is the purpose of the cytoplasm? Cytoplasm is a jelly-like substance that is responsible for supporting the organs and also providing nutrients to the cell. What is the mitochondria and what takes place in it? The powerhouse of the cell where cellular respiration takes place, where glucose is transferred into energy. What is the folded membrane of a mitochondria called? The cristae is folded which increases surface area meaning more energy can be generated. What takes place in chloroplast? Photosynthesis Why do the thylakoids stack? Thylakoids stack is called grana, the stack to increase SA which means more energy can be generated. Why do plants have a cell wall? To provide its rigid structure since they don't have bones. What is an enzyme? An enzyme is a protein that speeds up reactions without being used itself. (biological catalyst) What do substrates bind to on the enzyme? The active site What are the two types of active sites? Lock and key model. Induced fit model. What is denaturing? Because of high temp or high ph the hydrogen bonds are broken the shape of the active site changes. This means it can no longer bind to substrates and catalyse the reactions. This is irreversible. What are inhibitors? An inhibitor stops an enzyme from binding with its substrate by changing the shape of the binding to its active site. Competitive inhibitors? Binds to the active site Non-competitive inhibitors? Binds to somewhere else on the enzyme to change the active site What is simple diffusion? The Movement of small uncharged molecules across a semipermeable membrane. An area of high concentration to low concentration. What is facilitated diffusion? The movement of large and charged molecules from an area of high concentration to low concentration. The materials move across the semipermeable membrane through proteins. What is osmosis? The movement of water across a semipermeable membrane from an area of high water potential to an area of low water potential. What is active transport? Movement of substances from low concentration to an area of high concentration. The materials move across a semipermeable membrane through specific proteins in the cell membrane as protein pumps. What is cytosis? Transport mechanism of bulk quantities of molecules or large particles into and out of cells by folding of membranes. What is endocytosis? The taking in of substances into the cell by infolding of membranes What is tonicity? Measurement of water on either side of a semi-permeable cell membrane. What is hypertonic? High concentration of solutes outside the cell. What is hypotonic? High concentration of solutes inside the cell. What is isotonic? The concentration of solutes is the same inside and outside the cell. What will happen to an animal and plant cell for hypertonic? Animal cell will shrivel, plant cell will become plasmolysed What will happen to an animal and plant cell for hypotonic? Animal cell will burst, plant cell will become turgid What will happen to an animal and plant cell for isotonic? Animal cells will remain uncharged, plant cells will become flaccid. What is photosynthesis? Process of using light energy to convert water and carbon dioxide into glucose for the plant to use an energy to carry out its life process. What is the photosynthesis equation? 6CO2 + 6H20 = C6H1202 + 02 Why is light needed for photosynthesis? Light is needed for photosynthesis because light is absorbed by the chlorophyll found in the chloroplast. Chlorophyll is a green pigment that gives the plant colour. The light energy is turned into chemical energy. The chemical energy is produced so photosynthesis can occur. What is the light dependent phase of photosynthesis? Occurs in the thylakoid membrane of the grana. Solar energy hits the chlorophyll and the electrons contained there gain energy and are passed along a series of proteins to create ATP. Light energy is used to split water into oxygen and hydrogen. What is the light dependent equation? CO2 + ATP = C6H1202 What is the light independent phase of photosynthesis? Light independent does not require sunlight and happens in the stroma. Carbon dioxide delivered by energy carrying molecules to the stroma undergo a series of enzyme controlled reactions where carbon dioxide and hydrogen are joined together to make glucose. ATP produced by light dependent reactions is used to run this cycle. The glucose is stored as starch used in respiration. What increases photosynthesis? Higher temp, higher light intensity, higher co2 ions. What decreases photosynthesis? Too high temp. Decrease in water, light wavelength. What is cellular respiration? Converts glucose into ATP. ATP stores energy to fuel many life process including growth, mitosis, reproduction, photosynthesis and active transport. When would aerobic respiration take place? It will take place during everyday activities or prolonged but slower energy. The cells of the body require less ATP per second so enough oxygen can be delivered quickly enough to meet ATP demands. As a result the body can survive these action sfor longer durations without having to resort to anaerobic respiration. When would anaerobic respiration take place? It will take place during intense exercise when cells need large amount of ATP but the cells of the body cant get enough to meet the demands of ATP just through aerobic. Instead the cell switched to anaerobic respiration within the cytoplasm converting glucose into two pyruvate and 2 ATP molecules during glycosis for a fast and immidate production of ATP maintaining ATP demand in the cell process. What is the aerobic word equation? Glucose+Oxygen→Carbon Dioxide+Water+ATP What is the anaerobic word equation? Glucose→Lactic Acid+ATP What is DNA replication? DNA replication is the process by which a cell copies its DNA, creating two identical strands from one original strand. This is essential before mitosis, ensuring that each new cell receives an identical copy of the genetic information. What are the four main enzymes of DNA replication? Helicase: the unzipping enzyme DNA polymerase: the builder enzyme Primase: the primer enzyme Ligase: the glue enzyme What is mitosis? Mitosis is the process of cell division that results in two genetically identical daughter cells, each with the same number of chromosomes as the original parent cell. It occurs in somatic (body) cells and is crucial for growth, repair, and asexual reproduction. What is prophase? The first stage of mitosis, the chromatin condenses into visible chromosomes. What is metaphase? The chromosomes line up in the middle of the cell. What is anaphase? The spindle fibres pull apart the chromosome pairs. What is telophase? The new cell membrane forms creating two daughter cells. What is G0 Phase? The stable phase, he cell spends majority of their life here carrying out regular functions. What is the G1 phase? The growth phase, Cell caries out normal function but increases in size and production of proteins and organelles. What is the S phase? Replication, Dna undergoes replication to create two identical genomes. What is the G2 phase? Growth 2, Cells produce more proteins and organelles and create replicated DNA for any errors and damage. What is the M phase? Mitosis, PMAT.