Biology Chapter 1 2 3 Flashcards
1mm in micrometers
1000 micrometers
1 micrometer in nanometers
1000 nanometers
Different features of light microscope
Eye piece Objective lens Course focus Fine focus Stage Slide Light
What is a light microscopes magnification
x2000
Electron microscope magnification
x 2000000
Formula for size of an object (magnification)
Magnification=size of image/actual size of object
What is resolution
How clear an image is
Different parts of an animal cell
Nucleus Cytoplasm Cell membrane Mitochondria Ribosomes
How big is a animal cell
Around 10-30 mircometers
Roles of the nucleus
Controls the activities of the cell
Contains DNA and genes on the chromosomes which give it instructions for making proteins needed for making new cells
What is the role of the cytoplasm
A liquid gel where most the chemical reactions needed for life take place
What is the role of the cell membrane
Controls the passage of substances like glucose and mineral ions in the cell.
What is the role of mitochondria
Where aerobic respiration takes place, releasing energy for the cell. They are very small
What is the role of ribosomes
Where protein synthesis takes place making proteins for the cell
Features of plant cells (not included in animal cell)
Cell wall
Chloroplasts
Permeant vacuole
What is the role of the cell wall
It is mad of cellulose and strengthens and supports the cell
What is the role of chloroplasts
Contain chlorophyl
What is chlorophyl
Absorbs light so the plant can make food for photosynthesis
What is the role of a permanent vacuole
Filled with cell sap to keep the cell rigid to support the plant
What are eukaryotic cells
Animal cells and plant cells
What are prokaryotic cells
Single celled organisms. Their genetic material is not isn a nucleus but forms a single DNA loop as well as smaller loops called plasmids .
Features of bacteria cells
Slime capsule
Plasmids
Flagella
Genetic material
What is diffusion
Diffusion is the spreading off particles from a high conc to a low conc down a conc gradient
What tings effect the rate of diffusion
Different in conc
Temperature
Surface area
What substances move in and out of cells by diffusion
Glucose
Oxygen
Co2
What is osmosis
The movement of particles from a low conc to a high conc through a partially permeable membrane
Why is osmosis needed in plants
To help maintain turgor in the plant cells
What is turgor
The pressure in the plant cell that makes it rigid
What is active transport
An energy requiring process that moves substances from a low conc to a high conc
Where does active transport get the energy it needs
From the energy released from food in respiration
Where is active transport used
In plant root hair cells
In your gut
Why do plant root hairs cells need active transport
So they can absorb mineral ions required for healthy growth from very dilute solutions in the soil
Why is active transport needed in your gut
It enables sugar molecules used for respiration to be absorbed from the gut (low conc) to the blood (high conc)
In a body cell how many chromosomes are there
23 pairs
What are chromosomes
threadlike structures made of DNA molecules that contain the genes
What are genes
Chemical factors that determine traits
What is DNA
A complex molecule containing the genetic information that makes up the chromosomes.
What happens in mitosis
The cells nucleus divides
What happens in the cell cycle
Replication of DNA (doubles all the chromosomes)
Mitosis
Cell divides
What is differentiation
The process where cells become specialised and get a specific function
What is a zygote
A single new cell (when the sperm meets the egg)
What are embryonic stem cells
The cells in the embryo that haven’t been specialised yet
Where do adults have stem cells
Bone marrow
What are a group of cells called
Tissue
What are a group of tissues working together called
An organ
Or muscle
What are a group of organs working together called
An organ system
What does the muscular tissue do in the stomach
Churns the food and digestive juices together
What does the glandular tissue do in the stomach
Produces digestive juices that break down the food
What does the epithelial tissue do
Covers the inside and out side of an organ
What is glucoses chemical formula
C^6H^12O^6
What are carbohydrates made up of
Units of sugar
What are lipids
Fats and oils
What are lipids made of
3 fatty acids joined to a molecule of glycerol
What are proteins made up of
Long chain of amino acids
How many amino acids are there
Around 20
How do you test for starch
You put iodine in it and it will turn blue/black if if present
How do you test for sugars
Beneticts solution will turn red if sugar is present
How do you test for protein
Biuret reagent will turn purple if protein is present
How do how test for lipids
Ethanol will give a cloudy white layer if lipids are present
What is a catalyst
It increases the rate of chemical reactions without changing the chemical its self
What are enzymes
Biological catalysts
What is the lock and key theory
Where there is an enzyme with an active site and a substrate that fits perfectly in it
When the substate fills the active site it will split into products that will then leave the active site
What is metabolism
The sum of all the chemical reactions in the body
What things can effect enzyme reaction
Temp
PH
Why does temp effect the enzyme
Because high temp denatures the enzyme by changing its active site
What temp do most human enzymes work best at
37°
What enzyme breaks down carbs
Carbohydrase breaks it down into simple sugars
What enzyme breaks down protein
Protease breaks them down into amino acids
What enzyme breaks down lipids
Lipase breaks it down into fatty acids and glycerol
