Biology S3
🇬🇧
In English
In English
Practice Known Questions
Stay up to date with your due questions
Complete 5 questions to enable practice
Exams
Exam: Test your skills
Test your skills in exam mode
Learn New Questions
Popular in this course
Learn with flashcards
Manual Mode [BETA]
Select your own question and answer types
Other available modes
Complete the sentence
Listening & SpellingSpelling: Type what you hear
multiple choiceMultiple choice mode
SpeakingAnswer with voice
Speaking & ListeningPractice pronunciation
TypingTyping only mode
Biology S3 - Leaderboard
You may also like
Biology S3 - Details
Levels:
Questions:
173 questions
🇬🇧 | 🇬🇧 |
What is a species? | A group of organisms so similar that they can interbreed to produce fertile offspring. |
What happens if different species interbreed? | It is possible that a hybrid could be produced |
Why are hybrids usually sterile? | Due to the number of chromosomes they have |
What are some examples of hybids? | Zorse (zebra and horse), cama (camel and llama), liger (lion and tiger) |
What is variation? | All the differences which exist between members of the same species |
What is discrete variation? | A characteristic that can be used to divide up the members of the population into distinct groups |
What are some examples of discrete variation? | Eye colour, blood type, fingerprint type, hair colour |
What is continuous variation? | A characteristic that varies from one extreme to the other and does not fall into distinct groups |
What are some examples of continuous variation? | Height, mass, heart rate |
How is continuous variation displayed? | As a histogram |
What does a bell shaped curve show on a histogram showing continuous variation? | A normal distribution |
Where is genetic information stored? | On chromosomes in the nucleus |
What is meant by characteristics? | The appearance of the organism |
Where does genetic information come from? | Gametes, one set comes from the male and one set comes from the female |
What does haploid mean? | One set of information |
What does diploid mean? | Two sets of information |
What is a zygote? | A cell formed by a fertilisation event between two gametes |
Where is an egg fertilised? | In the oviduct |
What happens over the next few days after a zygote is created? | Mitosis (cell division) |
Why does mitosis take place? | To make more cells |
What happens after about 5 days from fertilisation? | It becomes a blastocyst which implants itself in the uterus? |
What is the placenta? | The organ that provides oxygen and food from the mother for the growth of the fetus. |
What is the uterus? | The muscular organ where the fetus grows and develops. |
What is the umbilical cord? | A cord connecting the baby to the placenta |
What is the amniotic sac? | A bag of watery fluid |
What is amniotic fluid? | Watery fluid protecting the developing fetus. |
What is the cervix? | The neck of the uterus |
What is the vagina? | Another name for the birth canal |
What are the four teratogen groups? | Chemical agents, infectious agents, physical agents and maternal conditions? |
What is an example of a chemical teratogen? | Thalidomide - a medication that was used for morning sickness (causes birth defects, many of the babies died within the first year of life) Recreational drugs (reduces blood flow to fetus, miscarriages, bleeding and deaths) |
What is an example of an infectious teratogen? | Mumps (a viral disease)- causes miscarriages. Listeria (a bacterial disease)- causes miscarriages, premature birth, infection to the newborn |
What is an example of a physical teratogen? | Radiation - causes mutations and deaths, defects can be passed on to the next generation. Mechanical Forces - causes hip dislocation and deformaties |
What is an example of a maternal condition teratogen? | Lack of something in diet (for example, iron) - can cause anaemia and stillbirths |
Why are chromosomes arranged in pairs? | One comes from the mother and one from the father |
What are some characteristics of someone with Down's Syndrome? | Slanting eyes, flattened nose, protruding tongue, thickening of hands and feet and learning difficulties |
What is different about someone with Down's Syndrome? | The have an extra chromosome in the 21st set. |
What is a mutation? | A change in the number or structure of chromosomes |
Why is Down's Syndrome a mutation? | It's a change in the number of chromosomes |
What are genes? | Sections of chromosomes |
What do genes code for? | Different characteristics |
Why do cells contain two copies of the each gene? | One from the mother, one from the father |
Each chromosome is a molecule of what? | Tightly coiled deoxyribonucleic acid |
What structure is DNA? | Double helix |
What do DNA bases do? | Hold the genetic code |
What are the rungs of the ladder? | DNA bases |
What does the age of the mother affect children with Down's Syndrome? | The older the mother, the more common Down's Syndrome is |
What is the nucleus? | The control centre to co-ordinate the cells activities |
What is each stand of DNA made from? | Repeated units called bases |
What are proteins made from? | Repeating units called amino acids |
The order of amino acids that make a protein is controlled by what? | The order of the bases on the DNA |
What are some ways to speed up a reaction? | Heat it, stir it, increase concentration, smaller particle size, increase pressure |
What does hydrogen peroxide turn into? | Water and oxygen |
How would you make hydrogen peroxide speed up it's reaction? | Add manganese dioxide or crushed grape cells |
What is a catalyst? | A chemical used to speed up a reaction but is itself not used up. |
What is an enzyme? | A biological catalyst |
How did tangerine cells speed up the reaction of hydrogen peroxide? | It acted as an enzyme |
What does the suffix ase mean? | It is an enzyme |
Why are enzymes required? | To speed up biological reactions without making them go too fast. They keep us alive. |
What does it mean by enzymes are specific? | Enzymes are different and do different jobs |
What is a degradation reaction? | A breaking down reaction |
What is a synthesis reaction? | A building up reaction |
Describe what happens in a degradation reaction? | An enzyme takes a substrate in and makes an enzyme-substrate complex. At the end, you have an unchanged enzyme and the products |
Describe what happens in a synthesis reaction? | An enzyme takes in substrates and makes an enzyme-substrate complex. At the end, you have the unchanged enzyme and a product. |
Do enzymes and their substrate(s) fit well together? What is the term to describe this? | Yes, perfectly - their shapes are complementary |
How are enzymes specific? | Enzymes fit only one type of substrate therefore they can only catalyse one reaction |
What are enzymes made of? | Proteins |
Where are the instructions for making enzymes kept? | In the DNA in the form of genes in the nucleus |
What is the active site? | The part of the enzyme that fits the shape of the substrate |
What is the substrate and products of catalase? | Hydrogen peroxide, water and oxygen |
What is the substrate and products of amylase? | Starch, maltose sugar |
What is the substrate and products of pepsin? | Protein, peptides then amino acids |
What is the substrate and products of trypsin? | Protein, peptides and amino acids |
What is the substrate and products of phosphorylase? | Glucose-1-phosphate, starch |
What is the substrate and products of lipase? | Fat, glycerol and fatty acids |
What is different about phosphorylase compared to enzymes like catalase, amylase and pepsin? | Phosphorylase is a synthesis reaction - meaning it takes something small and builds it up rather than taking something big and braking it down |
Describe how phosphorylase works in the growing of potatoes? | Potato plant leaves photosynthesise to create sugars, these sugars are transported to the roots, phosphorylase then turns the sugars into starchy potatoes |
What does boiling a leaf do? | It kills the leaf and stops it photosynthesising |
What is horticulture? | Cultivation of plants in gardens, greenhouses and on farms |
What does leaving a leaf in ethanol do? | Removes the green colour (chlorophyll) |
What is horticulture? | Cultivation of plants in gardens, greenhouses and on farms |
What is horticulture? | Cultivation of plants in gardens, greenhouses and on farms |
What does adding iodine to a leaf do? | Lets us see if the leaf contains starch |
What is horticulture? | Cultivation of plants in gardens, greenhouses and on farms |
What is photosynthesis? | The process by which green plants use carbon dioxide from the air and water from the soil to produce sugar and oxygen gas |
What is horticulture? | Cultivation of plants in gardens, greenhouses and on farms |
What does synthesis mean? | To build |
Where does photosynthesis take place? | In the chloroplasts |
What are the raw materials of photosynthesis? | Carbon dioxide and water |