Module 2 - Organisation of living things Flashcards
What are unicellular organisms?
A body that consists of only
one cell (bacteria, archaea,
protists).
what are colonial microcellular organisms?
A visible cluster of microbes growing on the surface/within a solid medium. The colony is made of clones descendent from a single ancestor.
What are multicellular organisms?
Consists of many differentiated cells in a working body. They rely on specialised cells to perform specific functions and interact with other cells in the body.
What is cell differentitation?
- The process that stem cells undergo to become specialised.
- Controlled by genes, theses genes allow for the production of certain proteins that determine what characteristics the cell will have.
- predetermined by the location of the cells in relation to other cells in the organism. (Cells located on the surface = skin)
What are the 4 main tissue types?
- Epithelial
- connective
- nervous
- muscle
What is epithelial tissue?
Tissue that covers the bodies surface, protects organs and forms glands.
It does not contain blood vessels and relies on connective tissues for nutrients.
What is connective tissues?
Provides support and ensures that different parts of the body are bound together and protected from damage.
Contain protein fibres, collagen and elastine.
What are nervous tissues?
Made up of neurons that send messages to and from the brain. Have a large surface area.
What is are the three types of muscle tissues?
- Smooth (pushing substances through body)
- Skeletal ( Attaches bone to muscle)
- Cardiac (allows for continuous pumping of the heart)
What is cell speciation?
Cells adapt to take on a specific task in a body. Differentiation is a less specialised cell that becomes more distinct in form and function.
Hierarchical Structure?
Tissue - a group of cells Organelles --> Cells --> Tissues --> Organ --> System that act together to perform a specific function Organ - a collection of tissues joined together to serve a common function System - a group of organs that work together to carry out a particular task
What is an autotroph? What are the two types of autotrophs?
An organism that makes its own food. (eg. trees)
Phototrophs and Chemotrophs.
What is a heterotroph?
An organism that obtains nutrients elsewhere. (eg. Rabbit)
What are vascular plants?
Plants that posses a transport system to move substances form one part of the plant to another.
What are non vascular plants?
Plants that absorb and excrete substances through diffusion and osmosis.
what are the two types of vascular tissue?
Xylem and Phloem.
What is the xylem and what is it responsible for?
TRANSPIRATION
Responsible for transporting water/sap and minerals throughout the plant.
Only flows in ONE way. (Roots to leaves)
Uses passive transport. (no energy)
What is the phloem? What is it responsible for?
TRANSLOCATION
Transports glucose and amino acids to the plant.
Flows in both directions.
Requires energy to transport things.
what is the transpiration-cohesion-tension theory?
Explains how water moves against gravity from root to leaf through the xylem.
Transpiration in leaves creates tension in the cell walls of mesophyll cells, which allows water
to be pulled up from the roots to the leaves. Cohesion (the pull between water molecules due to hydrogen bonds) also helps this process.
What is the source sink theory?
The source is where the nutrients originates and the sink is the location/s that requires the nutrients. Eg. In plants the leaves are the source of glucose and all other cells of the plant are considered the sinks.
what allows for gas exchange in plants and how does it do this?
Stomata are pores in the leaves of the plants that allow the movement of oxygen into and carbon dioxide out of the plant.
Mostly found in the underside of plants.
Guard cells protect the stomata and are able to swell or shrivel depending on water levels in plant.
What is the purpose of the leaf structure?
Cuticle and epidermis - reduce evaporation and prevent bacteria from entering. Palisade mesophyll - contains chloroplasts to carry out photosynthesis Stomata - contain guard cells that open and close to allow gases to enter and leave.
Leaves are the main organ in plants
responsible for photosynthesis.
What does the stem of a plant do?
The plant stem provides structural
support, transports water, gases, and
nutrients, and provides protection for
the plant.
What is the function of the respiratory system?
To move oxygen into cells and carbon dioxide out of cells.
What are the common characteristics to make the exchange of gases effective?
- Large surface area to volume ratio.
- A moist thin surface for easier diffusion.
- Close proximity to the respiratory system.
What are the parts to the respiratory system?
- Nasal cavity
- mouth
- larynx
- lungs
- bronchi
- diaphragm
- epiglottis
- trachea
- bronchioles
- alveoli
How do insects respire?
The tracheal system is a network of small tubes that carry O2 to the body. The air enters/leaves the system through spiracles along the thorax and abdomen.
How do fish respire?
Gills are used to respire. Gill -> gill arch -> gill filaments -> lamella (maximise surface area). Blood in capillaries flow through the lamella in the opposite direction of water.
What is chemical digestion?
The process of breaking down food into small, digestive parts. This is done by breaking food molecules into their chemical building blocks with enzymes.
What is mechanical digestion?
A physical process where food is broken down into smaller pieces to increase surface area and mobility.
What are the three digestive enzymes?
Protease, Lipase and Amylase.
What is the duodenum?
Start of the small intestine.
Chyme enters slowly through the
pyloric sphincter.
What is the jejunum?
Middle part of the small intestine.
Contains the villi which are tiny
projections wrapped in capillaries
that diffuse nutrients into the
bloodstream
What are villi?
Villi are protrusions in the intestinal wall that
have a large surface area to volume ratio that
allow rapid diffusion of nutrients into the blood
stream.
What is the ileum?
End of the small intestine.
Reabsorption of many vitamins.
What is an open circulatory system?
Compromised of one or more hearts and open ended blood vessels. They have lower pressure therefore less efficient than closed systems. Pump haemolymph instead of blood.
What is a closed circulatory system?
Transports waste, nutrients and gases in and out of the organism. Travels in blood vessels in the transport medium of blood.
What animals have an open circulatory system?
invertebrates
What animals have a closed circulatory system?
Found in ALL vertebrate animals.
What does the lymphatic system allow?
The flow of tissue fluid.
Its used go prevent build up of interstitual fluid in tissue, lymph vessels absorb this.
What are the types of blood vessels?
- Arteries
- Veins
- capillaries
Describe arteries.
carries oxygenated blood away from the heart. Blood is under very high
pressure and therefore has thick muscular walls to withstand the pressure. The
walls of these vessels are also highly elastic to allow them to expand and contract
as blood moves through them.
Describe veins.
carries deoxygenated blood towards the heart (i.e. blood visits). Blood is
not under much pressure so the walls of veins are thinner but the vessel itself has
a larger diameter. They contain internal valves at regular intervals to ensure the
blood does not backflow so that all the blood can return to the heart.
Describe capillaries.
tiny blood vessels in close contact with all body tissues. They are
only one cell thick and move products in and out of the blood via diffusion.
What is blood made up of?
Red blood cells
White blood cells
Platelets
Plasma
Function of red blood cells?
transport substances
Function of white blood cell ?
protects against infections
Function of plasma?
fluid portion (mainly water)
Function of platelets?
created blood clots when bleeding occurs
What do both plants and animals have to ensure effective transport of substances?
A system of vessels in which substances are transported
A suitable transport medium
A mechanism to ensure that substances move to the places that need them
What are the differences in plant and animal transport systems?
The type of transport structures
The substances that are transported
The mechanism that drives the movements of these substances