30592204
Descrição
FlashCards por Malachy Moran-Tun, atualizado more than 1 year ago
|
|
Criado por Malachy Moran-Tun
aproximadamente 3 anos atrás
|
|
| Questão | Responda |
| What is an Enzyme? | A biological catalyst that speeds up chemical reactions without being used up |
| Define the Following: > Active Site > Optimum > Enzyme-Substrate Complex > Denatured > Saturation Point | Active Site - the part of the enzyme that the substrate binds to Optimum - the point where there is the most enzyme activity Enzyme-Substrate Complex - the enzyme and the substrate bound together Denatured - the active site's shape has changed so the substrate cannot bind to it Saturation Point - the starting point where the enzyme activity becomes constant due to substrate concentration |
| How does the Lock and Key Model of an Enzyme Work? | > Substrates attach to the active site of an enzyme > Creating an enzyme-substrate complex > Enzyme breaks down the substrate into products |
| Why does Enzyme Activity Decrease when the Temperature is Above the Optimum? | > Enzymes become denatured: > The active site's shape changes > Substrates cannot bond with the active site > Less enzyme-substrate complexes |
| Why does Enzyme Activity Increase as the Temperature Rises? | > Molecules' speed increases > There is more kinetic energy > From the thermal energy / temperature > Leads to an increase in collisions with the enzyme's active site > Increasing enzyme-substrate complexes |
| Why does Enzyme Activity Decrease when the pH is Above the Optimum? | > Enzymes become denatured: > The active site's shape changes > Substrates cannot bond with the active site > Less enzyme-substrate complexes |
| Why does Enzyme Activity Decrease when the pH is Below the Optimum? | > Enzymes become denatured: > The active site's shape changes > Substrates cannot bond with the active site > Less enzyme-substrate complexes |
| Why does Enzyme Activity Stay Constant when the Substrate Concentration is Above the Saturation Point? | > All the enzymes in the solution are enzyme-substrate complexes > Since there are enough / more substrates than enzymes > So substrates do not have more enzymes to bond with |
| Why does Enzyme Activity Increase as the Substrate Concentration Rises? | > Increase in substrates > Increase chance in collisions with the enzyme's active site > More enzyme-substrate complexes |
| What are the Functions of the Following: > Cell Membrane > Cell Wall > Nucleus > Cytoplasm > Ribosome | Cell Membrane - controls what enters and exits the cell Cell Wall - provides structure and support to the cell Nucleus - controls the cell and its functions Cytoplasm - allows for chemical reactions to occur Ribosome - used in protein synthesis to produce proteins from amino acids |
| Order the Measurements from Metre to Picometre, including their respective Symbols | Metre (m) Millimetre (mm) Micrometre (μm) Nanometre (nm) Picometre (pm) |
| What are the Four (Main) Adapted Structures in a Sperm Cell and their Functions? | 1. Acrosome - contains enzymes which digest the outer capsule of an egg cell to allow fertilisation 2. Mitochondria - releases energy through respiration to allow for quick movement 3. Long Tail - allows the cell to quickly move forward towards the egg cell for fertilisation 4. Haploid Nucleus - contains half of all chromosomes to allow for fertilisation of an egg into a zygote |
| What are the Four (Main) Adapted Structures in an Egg Cell and their Functions? | 1. Large Cytoplasm - stores additional nutrients for the embryo during its development 2. Cell Membrane - hardens after fertilisation to stop additional sperms from entering 3. Jelly Layer - also hardens after fertilisation 4. Haploid Nucleus - contains half of all chromosomes to allow for fertilisation of the egg into a zygote by a sperm |
| What is the Main Adapted Structure of a Epithelial Cell and its Function? | Fine Hair-Like Extensions - either part of the membrane, or separate structures (cilia) which sweep from side to side to move things across the cell surface |
| What is a Chromosome? | A coiled up, thread-like length of DNA found in all cells |
| What are Diploid Cells and Haploid Cells? | Diploid - contains 2 complete sets of chromosomes (46 in humans) Haploid - contains one set of chromosomes (23 in humans) |
| What is Mitosis? | > A type of asexual reproduction > Used for growth or replacement of damaged cells > Creates two identical cells |
| What is the Order of the Cell Cycle? | Interphase Prophase Metaphase Anaphase Telophase Cytokinesis |
| What happens in Interphase? | > Cell increases the amount of subcellular structures (e.g. mitochondria and ribosomes) > Cell duplicates DNA > DNA forms X-shaped chromosomes |
| What happens in Prophase? | > Chromosomes condense > Membrane around the nucleus breaks down > Chromosomes lay free in the cytoplasm |
| What happens in Metaphase? | > Chromosomes line up at the centre of the cell |
| What happens in Anaphase? | > Spindle fibres pull chromosomes apart > Chromatids (split chromosomes) are pulled to opposite ends of the cell |
| What happens in Telophase? | > Membranes form around each set of chromosomes > These become the nuclei of the new cells > Here, the nucleus has fully divided |
| What happens in Cytokinesis? | > Cytoplasm and cell membrane divide > Forms two separate cells |
| What is the Central Nervous System? | > The brain and the spinal chord > Coordinates a response due to a stimulus > Sends information to an effector, which responds accordingly |
| What are the 3 Types of Neurones and their Function? | 1. Sensory - carry nerve impulses from receptor cells to the CNS 2. Relay - carry impulses from sensory neurones to motor neurones / CNS 3. Motor - carry impulses from the CNS to effector cells |
| What is the Structure of a Sensory Neurone? | > Long Dendron, which carries nerve impulses to the cell body (in the middle) > Short axon, which carries impulses from the cell body > (Sometimes) has a myelin sheath |
| What is the Structure of a Relay Neurone? | > Many short dendrites, which carry nerve impulses to the cell body > An axon, which carries nerve impulses from the cell body > (Sometimes) has a myelin sheath |
| What is the Structure of a Motor Neurone? | > Many short dendrites, which carry nerve impulses to the cell body > One long axon, which carries nerve impulses from the cell body > Myelin sheath |
| What is the Myelin Sheath and its Purpose? | > Fatty layer that surrounds the axon > Acts an an insulator to speed up nerve impulses > Lowers the chance that electrical signals are lost |
| What are Synapses? | > Used to connect two neurones > Transfers the nerve signal by chemicals, rather than electrical signals > Neurotransmitters diffuse across the gap between the neurones > Neurotransmitters set off a new electrical signal > Slower than regular neurone transmission |
| What are Reflexes? | > Automatic and rapid responses to stimuli > Help prevent injury |
| What is the Reflex Arc? | > Stimulus is detected by receptor cells (e.g. a sting) > Receptor cells send an electrical signal across a sensory neurone > Rather than going to the brain, the signal travels through the spinal chord (or an unconscious part of the brain) > Impulses are passed along a relay neurone by a synapse > Impulses travel along a motor neurone by a synapse > The impulse reaches an effector cell (e.g. a muscle or gland) |
| Why are Reflexes Quicker than Normal Responses? | > The signal does not pass through the brain > So, less time is spent thinking about a response > They are automatic |
| What is Meiosis? | > Method of cell division > Creates 4 genetically different haploid cells > Cells divide twice > Takes place in the testes and ovaries |
| What happens in Meiosis? | > Before cell divides, it duplicates its DNA, so there's enough for each new cell First Division: - Chromosomes line up in pairs, at the centre of the cell - Pairs are pulled apart, so each new cell has one copy of each chromosome - Each new cell has a mixture of chromosomes - This creates genetic variation Second Division: - Chromosomes line up again, at the centre of the cell - Chromosomes are pulled apart into chromatids - Creates four haploid daughter cells - These are genetically different gametes |
| What is a Gene? | A section of DNA that often contains instructions for a specific protein |
| What is a Genome? | > All of the DNA in an organism > Each body cell contains a copy of the genome |
| What is DNA's Structure? | Double-helix (2 strands that are joined together and twisted around each other) |
| What are the 4 Bases in DNA and their Pairings? | Adenine, Thymine, Guanine, Cytosine A = T G ≡ C |
| Fill in the blank: Each base in DNA is attached to a _____ called __________, and each sugar is attached to a __________ _________. This grouping is called a ________ | Each base in DNA is attached to a SUGAR called DEOXYRIBOSE, and each sugar is attached to a PHOSPHATE GROUP. This grouping is called a NUCLEOTIDE. |
| What holds the Base Pairs together in DNA? | Hydrogen Bonds |
| What are the Two Stages of Protein Synthesis? | 1. Transcription 2. Translation |
| What is RNA? | > Single stranded molecule similar to DNA > Uses Uracil instead of Thymine |
| What happens in Transcription? | Produces mRNA to form DNA. mRNA is small enough to leave the nucleus and go to the ribosome. > DNA in the nucleus unwinds due to the RNA polymerase enzyme, which binds to a non coding region > mRNA nucleotides pair up to the template strand with their complementary base pairs > Hydrogen bonds break between the mRNA nucleotides and the DNA. The mRNA is now a single strand with complementary base pairs to DNA |
| What happens in Translation? | Occurs in the cytoplasm, with the help of ribosomes. > tRNA molecules have an amino acid and anti-codon on each end, which are complementary to a codon (3 bases in DNA) > Each anti-codon is complementary to a codon on DNA > tRNA binds temporarily to the mRNA, which brings each amino acid on the molecule closer together > Peptide bonds are formed between amino acid, making a polypeptide chain form > Process continues until a "stop" codon is reached |
| What is a Phenotype? | The physical characteristics determined by alleles |
| What are Alleles? | Different forms of a gene |
| What is a Genotype? | The combination of alleles that an organism has |
| Hip hip hooray... | for DNA! |
| What is a Recessive Allele? | An allele that doesn't change the phenotype (physical characteristic) but could be passed on |
| What is a Dominant Allele? | An allele that always affects the phenotype |
| What is a Homozygous Gene? | When both alleles for a gene are the same in an organism i- i mean gey |
| What is a heterozygous Gene? | When both alleles for a gene are different in an organism |
| In Punnett Squares, what do Capital and Lowercase Letters mean? | CAPITAL IS DOMINANT lowercase is recessive |
| What is a Co-Dominant Allele? | An allele that are both expressed in the phenotype, usually blood types (e.g. AB blood) |
| What is a Mutation? | > Change in a gene that creates a new allele > Often occurring in cell division |
| What is Evolution? | Change in characteristics of a species over a long period of time |
| What is a Fossil? | The preserved remains of a dead organism (rip) from millions of years ago |
| What is Natural Selection? | When the best adapted individuals survive longer changes |
| What is Inheritance? | When the characteristics of an individual vary due to differences in the genes, some of which are caused by mutations |
| What is Environmental Change? | When the conditions in an area change, e.g., a lack of food resources causes competition between organisms |
| What are the Steps to Describe Evolution? | G.E.N.I.E.: 1. Genetic Variation 2. Environmental Change 3. Natural Selection / Survival of the Fittest 4. Inheritance 5. Evolution |
| What is Convergent Evolution? | When one characteristic evolved similarly and separately in a different species |
Quer criar seus próprios Flashcards gratuitos com GoConqr? Saiba mais.