Cells Flashcards
What do cells need to survive?
Cells require energy inputs, including light energy or chemical energy in complex molecules, and matter, including gases, simple nutrients and ions, and removal of water to survive
What is the difference between prokaryotic and eukaryotic cells?
Prokaryotic and eukaryotic cells have many features in common, which is a reflection of their common evolutionary past, but prokaryotes lack internal membrane bound organelles, do not have a nucleus are significantly smaller than eukaryotes, usually have a single circular chromosome, and exist as single cells
What is metabolism
Metabolism describes the sum total of the physical and chemical processes by which cell components transform matter and energy needed to sustain life.
Define cell membrane
Semi porous plasma membrane around the outside of cells made of a bilateral comprising of phospholipids.
Function of the cell membrane
Establishes cell boundaries, ensures contents are held inside cells, allows movement if some substances in and out of the cell, but not others (semi permeable)
Define nucleus.
An organelle within a eukaryotic cell that is enclosed with a double membrane and contains pores in the nucleus.
What is the function of the nucleus
Allow substances in and out, contains chromosomes which carry DNA, and is the site if DNA transcription within the cell
What is the cytoplasm
All contents of the cell, other than the nucleus.
Function of cytoplasm
Synthesises proteins and fats; also first stages of ATP release
What is cytosol
Semi fluid substance in the cytoplasm
What is the mitochondria
Has an inner and outer membrane, and many layers of folded membrane inside (Cristae)
Function of the mitochondria
It is where most of the process of cellular respiration occurs.
What is the function of chloroplasts?
Where photosynthesis occurs
What is the function of the rough endoplasmic reticulum
Isolates and transports proteins synthesised by ribosomes
Function of ribosomes
Make protein from amino acids
Function of smooth endoplasmic reticulum
Formation and transport of lipids and steroid hormones. Also protects cell from harmful compounds eg drugs
Function of Golgi apparatus
Where lipids and proteins are modified and sorted. Like a processing station for the cell. Secretory vesicles break off the Golgi apparatus and expel materials made by the cell.
Function of lysosomes
Contain digestive enzymes that split complex chemical compounds into simple ones, including getting rid of organelles thT no longer function properly. Can also chase cell death
What is the function of vacuoles
Storage and digestion in animals. In plants, main role to maintain turf or pressure
Function of centrioles
Help cell division and formation of spiracle fibres
Function of cell wall
Give plants turgidity and strength
Draw the model of the cell membrane (fluid mosaic model)
Refer to book for diagram
How does movement of materials across membranes occur?
Passive process: diffusion, facilitated diffusion and osmosis
Active process: include active transport, endocytosis and exocytosis
What are the factors affecting exchange materials across the membrane?
Surface area to volume ratio, concentration gradient, physical and chemical nature of the materials being exchanged
What happens to biological molecules when they are synthesised from monomers?
Complex structures including carbohydrates, proteins and lipids are produced
What factors control biochemical processes in the cell?
Nature and arrangement of internal membranes and the pressure of specific enzymes
Draw a prokaryote cell
Refer to book
Convert mm in to micrometers
1mm equals 1000micro metres
Draw and label an animal cell
Refer to book
Draw and label a plant cell
Refer to book
Refer to book for magnification formulas
:)
What are organic molecules?
Often large molecules made up of smaller subunits, bonded together in various ways
List organic molecules
Carbohydrates, lipids, proteins, nucleic acid
What is a polymer
Compounds made of subunits
What are carbohydrates
Molecules containing carbon, hydrogen and oxygen
Carbohydrates as a monosaccharide, dosaccharide and a polysaccharide
Mono- sugar/glucose
Di- sucrose
Poly- cellulose
Roles of carbohydrates
Source of energy for cells, structuctural support in plant, outer coating of insects and spiders
What are proteins
Large molecules made of subunits called amino acids that contain, carbon, hydrogen, oxygen, nitrogen and comets es Sulfur and phosphorous
How do amino acids from to make proteins?
They are bonded together by peptide bonds to make protein
What are lipids
Molecules of fats, oil and water containing hydrogen, carbon and oxygen
What is nucleic acid?
DNA and RNA
Function of DNA
Codes for production of proteins
Function of RNA
Transfer DNA codes to ribosomes for production of proteins
Why is the cell membrane referred to as a fluid mosaic model
Fluid because molecules,es that make it home are onctantky changing and mosaic because it is composed of many different types of molecules
What are phospholipid molecules
Lipid molecules containing a phosphate group
What is a phospholipid by layer
Two layers of phospholipids
Where does aerobic respiration occur?
Mitochondria
Where does anaerobic respiration occur?
Cytoplasm
Products produced in plants in aerobic respiration?
CO2 and H2O
What products produced in plants in anaerobic respiration
Alcohol and CO2
What is products produced in animals in aerobic respiration
CO2 and H2O
Products produced in animals in anaerobic respiration?
Lactic acid
Amount of ATP produced in aerobic respiration?
36-38 ATP
Amount of ATP produced in anaerobic respiration
2 ATP
Two organic substances that can be broken down in cellular respiration?
Glucose and amino acids
Two organisms in which fermentation occurs
Bacteria and plants
What is the word and chemical equation for photosynthesis
Carbon dioxide plus water in the presence of light and chlorophyll equals glucose and oxygen
Where does light dependent state occur in photosynthesis?
Thylakoids membranes
Where does light independent stage occur in photosynthesis?
Stroma
What are the reactants in the light dependent stage?
H2O
What are the reactants in the light independent stage?
CO2, H and ATP
What are the products in the light dependent stage
H+, O2 and ATP
What are the products in the light independent stage?
Glucose
What is pinocytocis?
Cell drinking, when minerals and vesicles are small
What is phagocytosis
Cell eating, when materials are large.
What is the similarity between pinocytocis and phagocytosis?
Both take substances into the cell
What is endocytocis?
Transport of materials into the cell. Materials are enclosed by a fold of cell membrane, which pinches shut to form a closed vesicles
What are the two types of endocytocis?
Phagocytosis and pinocytocis
What is exocytosis?
Transport of materials out of a cell where materials Are enclosed in a membrane.
What facilitates active transport
Requires ATP and substances are pumped across the membrane
What happens to to plant leaf during the night?
Starch to sucrose for export to cells in leaves
What happens to leaf during the day?
Glucose converts to sucrose and starch
What is fascilitated diffusion?
A form of passive transport, where transport proteins needed to move molecules across because they are water soluble
What are autotrophs
Organisms that make their own food, eg plants
What are phototropism
Green plants and algae are able to use light energy to synthesise their own organic materials
What are chemotrophs
Are able to harness the energy release in exergonic chemical reactions to synthesise their organic food
Label and draw cross section of a leaf
Refer to book
Label and draw a palisade cell
Refer to book
Label and draw chloroplast
Refer to book.
What does ATP consist of
Adenine, ribose and 3 phosphate groups
Cellular respiration definition
Chemical process by which organic molecules, taken in as food are broken down in the cell p, to release energy
