Biology Unit 2 Flashcards
What parts does a plant cell have, that an animal cell doesn’t?
Cell wall, vacuole and chloroplasts.
What is the purpose of a nucleus?
A nucleus controls the activities of the cell.
What is the purpose of a cytoplasm?
A cytoplasm is where most chemical reactions take place.
What part of a cell controls what comes in an out of the cell?
The cell membrane.
What cell part is responsible for respiration?
Mitochondria.
Where in the cell does protein synthesis occur?
Ribosomes.
Which cell part is responsible for photosynthesis?
Chloroplasts.
Define defusion.
The spreading of particles from a an area of high concentration to an area of low concentration.
Name the parts of the digestive system.
Pancreas, the stomach, small intestine, large intestine and the liver.
What do xylem and phloem do?
Transport food, water and minerals around the plant.
What is the part of a plant leaf that allows gas exchange? Where is it located on the leaf?
The stomata are located mostly on the underside of the leaf.
Write down the equation for photosynthesis.
light
Carbon dioxide + water ——-> glucose + oxygen
What cells does photosynthesis mostly occur in? Why?
Mesophyll cells. They contain lots of choloplasts. Chloroplasts contain chlorophyll.
Name five physical factors that affect organisms.
Temperature, nutrients, light, water, gasses (e.g. oxygen)
What is made up of long chains of amino acids?
Protein.
What do pathogens carry?
Antigens.
What are antigens attached to?
Pathogens.
What is an enzyme? And what does it do?
Enzymes are biological catalyst that brings about a specific biochemical reaction.
What effect do enzymes have on activation energy of a reaction?
Enzymes reduce the activation energy of a reaction.
What does it mean when we say that an enzyme is denatured? Don’t talk about pH.
An enzyme is called denatured when it’s active site changes shape. When it does, the substrate no longer fits. This happens at around 40 Celsius.
What effect does pH have on an enzyme?
pH affects the forces that hold the enzyme molecule together. Changes in pH can change the shape of the active site.
What enzyme catalyses the hydrolysis of starch into sugars?
Amylase.
Protease is an enzyme. What does it help us do?
Break down protein into amino acids.
Lipids are broken down into fatty acids and glycerol. What is the name of the enzyme that catalyses this reaction?
Lipase.
What is isomerise used for industrially?
It is used to convert glucose into fructose, which is much sweeter.
Name the type of respiration that doesn’t use oxygen.
Anaerobic respiration.
Does aerobic respiration involve oxygen?
Yup.
Glucose + oxygen –> carbon dioxide + water + energy.
What is this equation of?
Aerobic respiration.
Where is glycogen stored?
In the muscles.
Write down the equation for anaerobic respiration
Glucose —-> lactic acid + some energy
What causes muscle fatigue?
The buildup of lactic acid in the muscles.
What are chromosomes made up of?
DNA
How many chromosomes are there in a typical human body cell?
23
Difference between meiosis and mitosis in terms of the number of daughter cells?
Mitosis: 2 daughter cells
Meiosis: 4 daughter cells
What did Mendel study?
Principles of inheritance in pea plants.
What do we call different forms of the same gene?
Alleles.
What does a phenotype describe?
The observable, visual characteristics that an organism has.
What does a genotype tell us?
The genetic makeup of an organism.
What’s the difference between a homozygous and a heterozygous genotype?
Homozygous has 2 identical alleles.
Heterozygous has 2 different alleles.
What do we call a genotype that has 2 different alleles?
Heterozygous.
A homozygous has 2 alleles. Are they different or the same?
Same.
What makes it difficult for individuals to survive?
Predators, diseases, environmental changes, catastrophes.
Isolation, genetic variation and natural selection can lead to….
…a new species.
Name the parts of an animal cell
Nucleus, cytoplasm, rimosomes, mitochondria, cell membrane.
