Biology 1.1 - 2.2 Flashcards
Movement
an action by an organism or part of an organism causing a change of position or place
Respiration
the chemical reactions in cells that break down nutrient molecules and release energy for metabolism
Sensitivity
the ability to detect and respond to changes in the internal or external environment
Growth
a permanent increase in size and dry mass
Reproduction
the processes that make more of the same kind of organism
Excretion
the removal of the waste products of metabolism and substances in excess of requirements
Nutrition
as the taking in of materials for energy, growth and development
All cells have
Ribosomes for making proteins and Enzymes for respiration
What is classification?
The grouping of information or objects based on similarities
Why classify organisms?
to represent relationships among organisms
Taxonomic ranks
Kingdom
Phylum
Class
Order
Family
Genus
Species
Animalia
Chordata
Mammalia
Carnivore
Felidae
Panthera
Pardus
Change in Taxonomic Ranks
- From species to kingdom, decrease in similarity but increase in numbers
- From kingdom to species, increase in similarity but decrease in numbers
- As one goes from the kingdom to the species (downward), the increase in the similarity between organisms occurs
- There are fewer numbers of different kinds of organisms
Binomial System
A system that gives organisms a 2 word name showing the genus and species
Define same species
Organisms that are able to produce fertile offspring and do not normally interbreed with other groups of organisms.
How DNA helps with classifications
- MORPHOLOGY - overall form and shape of the body, e.g. legs, wings etc…
- ANATOMY - detailed body structure using dissection
DNA
- Deoxyribose nucleic acid
- DNA is made of 2 strands that have been twisted together
- It is genetic material that has been passed on from one generation to another.
- It looks like a ladder that has been twisted
- The rungs of the ladder are called bases and they form pairs
- A forms a bond with T
- C forms a bond with G
- The bases can be arranged in any order
- If you compare the base sequences in the DNA of organisms of two different species, the more similar the base sequences, the more closely related the species are presumed to be related to one another
- Evolutionists claim that they have a more common ancestor than species that have less similar base sequences.
Plants Kingdom
Use light energy to produce food during photosynthesis; cells have a cell wall made from cellulose. E.g. Roses, oak, trees, wheat. Flowering and non-flowering plants
Animals Kingdom
Feed on other organisms; multicellular, which means their bodies are made up of lots of different cells; no cell walls. E.g. Slug, ladybirds, lions. Jellyfish, worms, arthropods, mollusks, echinoderms, amphibians, fish, reptiles, birds and mammals
Fungi Kingdom
Make spores instead of seeds when they reproduce; cells have a cell wall made from chitin. E.g. Yeasts, mushrooms, molds
Protoctista Kingdom
Most made up of just one cell. E.g. Algae, euglena, amoeba
Prokaryotes Kingdom
Have no nucleus; have a cell wall but not made from cellulose. Single-celled organisms with no nucleus. E.g. Bacteria and primitive algae
Protoctists
Single-celled organisms with a nucleus. E.g. paramecium
Animals
- Animals are the most complex organisms on Earth
- They are multicellular organisms
- They ingest food made by other living organisms
- Their cells have a nucleus, but no cell walls or chloroplasts
- They are divided into vertebrates (backbones) and invertebrates (no backbone)
- Vertebrates include mammals, amphibians, reptiles, birds and fish
Plants
- Plants have leaves, stems and roots
- Plants contain chlorophyll, a green pigment necessary for photosynthesis, a process in which plants convert energy from sunlight into food
- Their cell walls are made sturdy by a material called cellulose, and they are fixed in one place
- Plants are divided into 2 groups: Flowers and fruit producing plants and those that don’t produce flowers or fruits, e.g. ferns and mosses
- They include garden flowers, agricultural crops, grasses, shrubs, ferns, mosses and conifers
Animal Kingdom
Vertebrates
- Birds
- Amphibians
- Reptiles
- Fish
- Mammals
Mammals
Vertebrates
Warm-blooded
Give birth to live young
Covered in hair or fur
Suckle their young
E.g. elephants, humans, bats, rodents, dolphins, dogs, whales, monkey
Birds
Vertebrates
Warm blooded
Lay eggs
Covered in feathers
Have a beak
E.g. eagles, ostrich, chicken, hawk, kiwi, sparrow, condor, puffin
Fish
Vertebrates
Cold blooded
Covered in scales
Have gills
Lay eggs
E.g. trout, skate, tuna, roach, salmon, perch, goldfish
Reptiles
Vertebrates
Cold blooded
Lay eggs
Covered in dry scales
E.g. cobra, tortoise, iguana, viper, python, chameleon, crocodile, komodo dragon
Amphbians
Vertebrates
Cold blooded
Have lungs and gills
Have moist skin
Llay gel covered eggs
E.g. toad, frogs, salamanders
Invertebrates
- Mollusks
- Flatworms
- Coelenterates
- Roundworms
- Segmented worms
- Echinoderms
- Arthropods (Crustaceans, Insects, Arachnids, Myriapods)
Arthropods
Animals with joint legs but no backbone
Waterproof exoskeleton (hard exterior)
Insects
2 pairs of wings
3 body parts
3 pairs of jointed legs
E.g. bee, wasp, dragonfly, locust, grasshopper, butterfly, ladybird, beetle
Arachnids
Have 2 body parts
4 pairs of legs
E.g. scorpions, ticks
Myriapods
Body has many segments
Each segment has jointed legs
E.g. centipedes, millipedes
Crustaceans
More than 4 pairs of legs
Breathe through gills
E.g. lobster, woodlice
4 main groups of plants
- Flowering plants
- Conifers
- Mosses
- Ferns
Flowering plants
Have flowers
Make seeds
Have veins in leaves
Have roots of stems
Seeds are embryonic plants with its own food supply
Spores are reproductive particles with chromosomes
Monocotyledonous plants
1 cotyledon
Strap like leaves
Parallel veins
Flower parts divisible by 3
E.g. kaffir lily
Dicotyledonous plants
2 cotyledons
Broad leaves
Branching veins
Flower parts divisible by 4 or 5
Cotyledon
Where food is stored in a seed
Ferns
No flowers or cones
Make spores on bottom of leaves
Conifers
Don’t have flowers
Make seeds on cones
Leaves are needle shaped
Have roots and veins
Mosses
Live in shady moist places
Are very small
Don’t make seeds
Make spores
Classification of viruses
- Viruses are not classified as living things as they are not made of cells
- Viruses are very small, approximately 100 nm across (1 nm = 1/1000000 of a mm)
- Viruses reproduce by invading other cells
Viruses, e.g. HIV
- Very small
- Not cells
- Contain a strand of DNA or RNA (genetic materials)
- Surrounded by a protein coat (capsid)
- Only life process they show is reproduction (inside host cells)
Virus reproduction
- Virus attaches to cell membrane
- Virus RNA enters cell
- DNA copy of the RNA is made
- Nucleus makes copies of the virus RNA
- New virus leave the cell
- Virus cores are made in the cytoplasm
Fungi
- Fungi are organisms that absorb nutrients from dead organisms or feces of survival
- They do not have chlorophyll and do not photosynthesise
- Multicellular
- Cells contain a nucleus
- Have cell walls but now made from cellulose (chitin)
- They include mushrooms, molds and yeasts (to make ethanol and bread)
Protoctista
- Protoctists are mostly single-celled organisms that have a nucleus
- They usually live in water
- Some protoctists move around, while others stay in one place
- Examples of protoctists include algae, paramecium and amoeba
Prokaryotes
- Bacteria are single-celled organisms that don’t have a nucleus
- There are more forms of bacteria than any other organism on Earth
- Some bacteria are beneficial to us, such as ones found in yogurt
- Others can cause us to get sick, e.g. tuberculosis (TB) and cholera
Bacteria
- Bacteria are single celled organisms
- Bacteria cells are about 1/1000th the size of animal or plant cells
Bacteria, e.g. E. coli
- Small
- Cell wall, cell membrane and cytoplasm
- No nucleus, DNA is a single coil
- Some have a slime capsule
- Some have flagella (for movement)
Fungus
- The main body of fungus is the mycelium, which is made of hyphae
- Fungal cells have cell walls made of substances such as chitin
Fungi, e.g. Mucor
- Multicellular fungi are composed of hyphae
- Cell walls made of cellulose or chitin
- Do not photosynthesise
- Some produce spores
Specialised cells have specific functions
- Ciliated cells: movement of mucus in the trachea and bronchi
- Root hair cells: absorption
- Palisade mesophyll cells: photosynthesis
- Neurons: conduction of electrical impulses
- Red blood cells: transport of oxygen
- Sperm and egg cells (gametes): reproduction
Cells
- All organisms are made of cells
- They are very small
- Large organisms contain millions of cells - multicellular
- Some are made of just one cell - unicellular (e.g. bacteria and yeast)
- Most cells have 3 basic parts (Nucleus, Cytoplasm, Cell membrane)
- But cells can be different shoes and sizes and also have different functions
- This is because they are specialised
- The shape of a cell is related to its function
- A specialised cell is a cell that has a special shape because it has a special function
Cell shapes
- Cells are not really flat, they are usually three-dimensional
- The 3D shape of the cell will be determined by its location in the body and the job that it does
Nucleus
Stores genetic information to help make protein. Kept on chromosomes.
Cell membrane
Very thin and controls what goes in and out. It is said to be semi-permeable.
Cell wall
Made of cellulose which is strong and helps to support the cell. Has big spaces between the fibres so it said to be freely permeable
Cytoplasms
Jelly-like substance containing many small structures called organelles. Many metabolic reactions take place here.
Vacuoles
A space in a cell surrounded by a membrane. Very large in plant cells storing cell products. Animal cells have smaller ones called vesicles.
Chloroplasts
Contain green coloured pigment called chlorophyll which absorbs light energy. Photosynthesis for making food occurs here, cells may contain starch grains as a result.
Ciliated Cells
- Key structure: Small hair-like structures that move in wave-like motion
- Main function: Movement of mucus in the wind pipes (trachea and bronchi)
Root hair cells
- Key structure: Large surface area due to extension on cell
- Main function: Absorption of water and minerals from the soil
- Also long and thin so that it has more places to take up water from the soil
Palisade Mesophyll cells
- Key structure: Lots of chloroplasts
- Main function: Make food by photosynthesis
Neuron cells
- Key structure: Very long and thin surrounded by insulation (myelin sheath)
- Main function: Conducts (electrical) nerve impulses
Red blood cells
- Key structure: Biconcave disc with no nucleus
- Main function: Maximum surface area for transport of oxygen
- Transports oxygen
- The shape helps it to have more room to carry oxygen. It also has no nucleus
Sperm cells
- Key structure: Tail and streamlined body
- Main function: To swim towards an egg
- Fertilises the egg cell
Egg cells
- Key structure: Large size with lots of cytoplasm
- Main function: Large food store for growing baby
- Fertilisation occurs when the sperm fuses with it
- Contains a large food store
Nerve cell
- Carries electrical signals to and from the brain
- Very long and thin
