Systems (Chapter 5 & 6) Flashcards
SAC Only
what are multicellular organisms composed of?
Multicellular organisms are composed of cells.
how do complex organisms survive?
Complex organisms, such as plants and animals, can survive because their cells are specialised, which means that they perform specific individual functions.
how must specialised cells interact to survive?
However, each of these specialised cells must interact and work together with all other cells of the body to survive.
As an organism increases in size and complexity, greater cooperation and coordination of cells is required to survive, and cells begin to arrange into four different levels: cells, tissues, organs and systems.
define cell
Cell the smallest functional unit of a living organism
define tissue
Tissue a cluster of cells which perform a shared function
define organ
Organ the organisation of tissues & cells into a distinct structure that performs a specific function
define system
System a collection of organs & tissues that perform specific functions for survival
Plant cells are organised into?
- Dermal tissue
- Vascular tissue
- Ground tissue
define dermal tissue
Dermal tissue that lines the outside of plants
define vascular tissue
Vascular tissue that is responsible for transporting water and nutrients around the plant
define ground tissue
Ground tissue which describes all other tissues in a plant.
Plant tissues are organised into many distinct organs & two different systems?
- root system
- shoot system
define root system?
The root system contains the roots
define shoot system?
The shoot system contains the leaves, stems, flowers, and fruit.
what are the Plant Organs?
- Leaves
- Flowers
- Fruits
- Stems
- Roots
function of leaves?
Sites of gas exchange and responsible for photosynthesis. In most species, leaves are organised to increase sunlight exposure.
function of flowers?
The sexual reproductive organs of flowering plants (angiosperms). Following the fertilisation of male and female gametes which are contained in pollen, seeds develop and the ovary of a flower grows into a fruit.
function of fruits?
Grown from a flower post-fertilisation. Fruits protect seeds and are often specialised to attract animals that aid with seed dispersal.
function of stems?
Support the leaves, flowers, and fruits, as well as transport water and nutrients between the roots and shoots.
function of roots?
Absorption and storage of water and nutrients from the soil. Roots are also responsible for anchoring the plant to the ground and providing structural support.
Animal cells combine to form the four major animal tissue types?
- Muscle
- Nerve
- Connective
- Epithelial
what are tissues further organised into?
Tissues are further organised into organs which make up systems such as the digestive system, respiratory system, and the immune system.
what are the common types of animal cells?
Common types of animal cells include skin, muscle, blood, nerve, and fat cells.
The four types of tissues in animals?
- Muscle tissue
- Nervous tissue
- Connective tissue
- Epithelial tissue
function of muscle tissue?
Contracts to exert a force. The three major types are skeletal, cardiac, and smooth muscle tissue.
function of nervous tissue?
Detects stimuli and transmits electrical signals
Composed of neurons that detect stimuli and carry electrical signals and glia that assist neuron signal transmission.
function of connective tissue?
Connects and supports other tissues and organ structures of the body`
function of epithelial tissue?
Composes the external and internal lavers of the body. These tissues assist in protection, secretion, and absorption.
what are the main animal systems?
- Digestive system
- Excretory system
- Endocrine system
- Skeletal system
- Muscular system
- Integumentary system
- Nervous system
- Immune system
- Respiratory system
- Blood circulatory system
- Reproductive system
function of digestive system?
Breaks down and processes food to be used by the body. Eliminates food waste that is not digested via egestion.
Organ and tissue examples of digestive system?
Stomach, liver, pancreas, small intestine, large intestine
function of Excretory system?
Removes waste substances from the blood via excretion. Also assists in the control of water balance in the body.
Organ and tissue examples of excretory system?
Kidneys, bladder, lungs
function of Endocrine system?
Responsible for the production and secretion of hormones which control and regulate bodily processes.
Organ and tissue examples of endocrine system?
Hypothalamus, pituitary gland, thyroid gland, thymus, pancreas, adrenal glands
function of skeletal system?
Provides an internal structure to support the body.
Works in tandem with the muscular system to enable movement of the body.
Organ and tissue examples of skeletal system?
Bones, joints, cartilage
function of muscular system?
Responsible for contractions in skeletal muscle, the heart, and other contractions throughout the body. Works in tandem with the skeletal system to enable movement of the body.
function of Integumentary system?
Protects internal body structures from the external environment.
Organ and tissue examples of muscular system?
Skeletal muscles, cardiac muscles, tendons
Organ and tissue examples of Integumentary system?
Skin, hair, nails, subcutaneous fat
function of nervous system?
Detects and processes sensory information to activate responses in the body.
function of Immune system?
Defends the body against infection. Contains the lymphatic system which transports lymph fluid around the body.
function of Respiratory system?
Responsible for removing carbon dioxide from the body and delivering oxygen to the blood via respiration.
function of Blood circulatory system?
Delivers oxygen and nutrients to the tissues of the body via blood.
function of Reproductive system?
In males, regulates the production of sperm and certain hormones.
In females, regulates the production of egg cells, certain hormones, ovulation, and nurturing offspring during development.
In both males and females, the reproductive system coordinates action for the purposes of reproduction.
Organ and tissue examples of Nervous system?
Brain, spinal cord, peripheral nerves
Organ and tissue examples of Immune system?
Bone marrow, spleen, thymus, tonsils, lymph nodes
Organ and tissue examples of Respiratory system?
Lungs, nasal passage, trachea
Organ and tissue examples of Blood circulatory system?
Heart, blood vessels (arteries, veins, and capillaries)
Organ and tissue examples of Reproductive system?
Testes, penis, ovaries, vagina, uterus, mammary glands
what are the levels of the body?
- cells
- tissues
- organs
- systems
- organisms
what are vascular plants?
Vascular plants contain vascular tissues, which transport water from the roots to the leaves of a plant, and glucose and nutrients throughout the plant.
what are the two types of vascular tissue?
The two types of vascular tissue, xylem and phloem, are responsible for moving water, minerals, and the products of photosynthesis throughout the plant.
Why does transport need to occur?
Materials need to be transported between the root system and the shoot system
what are the steps of transport in a plant?
- Roots absorb water and dissolved minerals
from the soil - Water and minerals are transported upward from roots to shoots as xylem sap.
- Transpiration, the loss of water from leaves (mostly through stomata), creates a force within leaves that pulls xylem sap upward.
- Through stomata, leaves take in CO, and expel 02.
The CO, provides carbon for photosynthesis. Some 02 produced by photosynthesis is used in cellular respiration. - Sugars are produced by photosynthesis in the leaves.
- Sugars are transported as phloem sap to roots and other parts of the plant.
- Roots exchange gases with the air spaces of soil, taking in O2 and discharging CO, In cellular respiration, 02 supports the breakdown of sugars.
There are two main types of vascular tissue?
- Xylem tissue
- Phloem tissue
what is Xylem tissue?
tubes that transport water, and minerals (such as potassium, nitrogen & phosphorus) in one direction from the roots to the leaves of a plant
- has no end walls
what is Phloem tissue?
tubes that transport sugars and other nutrients around a plant in both directions.
- end walls with perforations
what is the arrangement of xylem and phloem called?
The arrangement of vascular tissues is different between plant species. The close arrangement of xylem and phloem tissues are called vascular bundles.
what are the two ways of transport in plants?
Transpiration & Translocation
define transpiration
Transpiration is the evaporation of water from leaves and other parts of the plant
how is water lost in transpiration?
Water is lost through the stomata of leaves which are pores on the leaf’s surface that regulate gas exchange.
process of transpiration?
- Roots take up water from the soil
- Water is drawn up the stem to the leaves
- Water vapour lost from leaf pores in transpiration
how much water does a maple tree lose?
An average maple tree loses more than 200 L of water per hour during the summer!
what happens if water is not replaced in transpiration?
Unless this water is replaced by water absorbed by the roots, leaves will wilt and die
what vascular tissue is used during transpiration?
Xylem transports the water throughout the plant
how does transpiration work in depth (how does water travel up plant)?
- When water evaporates from the leaf the air pressure in the leaf becomes lower than the pressure in the roots. This creates a force that draws water up from the xylem.
- Because water likes to stick together (a characteristic called cohesion), even more water is drawn up than would be expected.
- This works the same way as when you ‘suck’ liquid up a straw – you create a lower pressure in your mouth compared to the atmospheric pressure, so water moves up the straw.
- Capillary action (adhesion of water molecules to the surface of the xylem), also helps water flow in the xylem.
what is translocation?
Sugar Transport
what vascular tissue does translocation?
Phloem carries phloem sap (food) from a sugar source to a sugar sink
what is a sugar source?
- an organ where sugar is being produced
- Usually leaves
what are sugar sinks?
- an organ that consumes or stores sugar
- Usually roots, growing stems, buds, & fruits
how does translocation move between sugar sources and sinks?
moves away from the sugar source to the sugar sink
how can translocation occur?
The movement of fluid in the phloem, a process called translocation, can occur in any direction, up or down the plant.
However, the fluid typically flows from source cells to sink cells.
what is the Mechanism of Translocation in Phloem?
The mechanism of phloem translocation is described in a model of phloem function called the pressure flow model. It proposes that water containing food molecules flows under pressure through the phloem.
Factors Affecting Transpiration Rate?
- At higher temperatures, more water evaporates from the leaves.
- In high light conditions stomata open, further increasing the amount of water lost to transpiration.
- As the humidity increases, less water can evaporate into the air and so the transpiration rate decreases.
- On windy days, this humid layer is blown away, encouraging water vapour to exit the leaf.
- When water availability is high the plant can then afford to increase the rate of transpiration & lose more water.
define Digestive system
the collection of specialised tissues and organs responsible for the digestion of food and absorption of nutrients
define Digestive tract
pathway of organs that food and liquids travel through after being swallowed, leading to digestion and elimination (also called the gastrointestinal tract or alimentary canal)
define Peristalsis
coordinated muscular contractions and relaxations of the digestive tract wall that move food along the system
define Chyme
mixture of partially digested food and digestive juices that passes from the stomach to the small intestine
what type of organism are we with producing food?
Unlike plants, animals are heterotrophs that have to consume other organisms or their products to obtain organic molecules.
what do organic molecules do?
Organic molecules provide chemical energy to the animal so they are able to live, survive and reproduce.
examples of organic molecules?
Organic molecules include carbohydrates, lipids, proteins, vitamins and minerals.
can we absorb food?
Food molecules are too large for animals to simply absorb into their bodies.
what is digestion?
Digestion is the breakdown of large food molecules into smaller forms that can cross plasma membranes and be used by the body.
importance of Carbohydrates?
Provide a source of immediate energy
importance of Lipids (such as fats)?
Energy storage in animals
importance of Proteins?
Structural components of cells, cell receptors, enzymes
importance of Vitamins?
While required in small amounts, many vitamins are used to make enzymes
importance of Minerals?
While required in small amounts, minerals are used in many structural components of organisms
There are two methods of food digestion?
- Physical (or mechanical) digestion
- Chemical digestion
what is Physical (or mechanical) digestion?
- Mechanical movement of organs and tissues causes the breakdown of food into smaller pieces
- Movements include chewing, muscle contractions and stirring of food and digestive juices by muscle movements
what is chemical digestion?
- Breakdown of food into smaller molecules that can be absorbed by digestive enzymes and stomach acid
- Three major types of digestive enzymes are amylases (act on carbohydrates), proteases (act on proteins) and lipases (act on lipids).
Steps of digestion?
- Ingestion
- Digestion
- Absorption
- Elimination/egestion
what is ingestion?
food is taken into the body. Teeth physically break down food into smaller pieces, enzymes in saliva chemically break down food into a soft mass that can be swallowed.
what is digestion?
occurs along the digestive tract, where the soft mass travels from the mouth and continues to be broken down both physically and chemically by a variety of organs.
what is absorption?
once food macromolecules are broken down into smaller molecules, they are absorbed across the plasma membrane of cells in the digestive tract into the bloodstream. Energy from food is now ready to be used by the body.
what is Elimination/egestion?
final step is the elimination of undigested food content that has travelled along the digestive tract and has not been absorbed. Undigested food is eliminated from the body as faeces.
what is the digestive system made up of?
In humans, the digestive system is made up of a number of organs including the stomach, liver, pancreas, and small and large intestines.
Each organ is a collection of cells forming specialised tissues.
order of digestion in organs and tissues?
- Oral cavity
- Salivary glands
- Oesophagus
- Stomach
- Liver
- Gallbladder
- Pancreas
- Small intestine
- Large intestine
- Appendix
- Rectum
- Anus
digestion in Oral cavity?
Beginning of the digestive tract where food is prepared for the stomach. Chews food and mixes it with saliva.
digestion in Salivary glands?
Glands that produce and release saliva into the mouth and oesophagus. Saliva which contains a starch-digesting enzyme called salivary amylase
digestion in Oesophagus?
Muscular tube lined with mucus that connects the mouth and stomach. Movement of the food is aided by waves of muscular contractions of the tube, known as peristalsis. Moves the bolus to the stomach.
digestion in Stomach?
Muscular organ that receives food from the oesophagus and temporarily stores it, where it is broken down by stomach acids, enzymes and peristaltic movements (ph 1 - 3). Mixes and churns food with gastric juice that contain acid and a protein-digesting enzyme called pepsin creating chyme.
digestion in Liver?
Large organ found in the abdomen that is involved in many metabolic processes including the breakdown of toxins. Site of bile production which aids in the digestion and absorption of fat.
digestion in Gallbladder?
Bile-storing organ that releases bile into the small intestine.
digestion in Small intestine?
Connects the stomach to the large intestine and is a major site of nutrient absorption during digestion. Divided into three sections: duodenum, jejunum and ileum. Digests food and absorbs nutrients into blood or lymph.
digestion in Pancreas?
An organ of the digestive and endocrine system that releases both digestive juices and hormones, namely insulin and glucagon which regulate blood glucose levels. Releases bicarbonate to neutralize intestinal contents; produces enzymes that digest carbohydrates, protein, and fat.
digestion in Large intestine?
Final area of absorption of water, vitamins and minerals along the digestive tract and the site of faeces production. Home to intestinal bacteria; passes waste material.
digestion in Rectum?
Final area of the large intestine that stores faeces for elimination.
digestion in Appendix?
Small sac of tissue that sits at the junction between the small and large intestines and is believed to play a role in immune functions.
digestion in Anus?
Opening at the end of the digestive tract that releases faeces.
what is the pharynx in digestion?
Swallows the chewed food mixed with saliva called bolus
are all animals digestive systems the same?
Different animal species have different food requirements and feeding behaviours.
what is a key determinant of an animals digestive system?
A key determinant of the structure and specialisation of an animal’s digestive system is its diet.
why are different animals have different digestive systems?
Herbivores, omnivores and carnivores contain different digestive systems due to their differences in diet.
define herbivore
Herbivore: an animal that almost exclusively feeds on plant material. (more stomachs, larger cecum, longer small intestine)
define omnivore
Omnivore: an animal that eats a variety of food from plants to other animals.
define carnivore
Carnivore: an animal that almost exclusively eats meat. (one stomach, smaller small intestine, teeth)
define Excretory system
the collection of organs and tissues that remove excess, waste materials from the body.
define Urinary tract
the series of channels in which urine is produced and excreted from the body
define Urea
the main nitrogenous product of protein breakdown in mammals. Excreted in urine.
define Urine
a fluid formed by the kidneys and stored in the bladder. One of the body’s major ways to remove excess water, solutes and waste substances from the blood
define kidneys
a pair of bean-shaped organs that are responsible for removing waste substances from the blood and the production of urine
define nephron
a functional unit of the kidney consisting of a glomerulus and tubule system through which filtrate passes and urine is produced
what happens during cellular processes?
During cellular processes, the human body accumulates unwanted waste materials within cells.
what do waste materials include?
Waste materials include: carbon dioxide from respiration, toxins and nitrogenous waste from protein breakdown.
what does excretory system do?
The body has a specialised system called the excretory system that removes excess and unwanted waste substances from the body and maintains the ideal concentration of water and solutes (ions).
what are the organs and tissues of the excretory system?
Organs and tissues that make up the excretory system include: kidneys and bladder.
Wastes that need to be disposed of and their sources?
ammonia - protein metabolism
urea - processing of ammonia
carbon dioxide - cellular respiration
lactic acid - anaerobic respiration
excess salts - food eaten
hydrophobic substances - food eaten
bile - liver
excess water - drinking
what are the parts of the excretory system?
- adrenal glands
- kidneys
- ureter
- urethra
- bladder
what is a major component of the excretory system?is it responsible for?
A major component of the excretory system is the urinary tract, which is responsible for filtering waste materials out of the blood and excreting these materials in urine.
what does the urinary tract consist of?
- Kidneys
- Ureters
- Bladder
- Urethra
where are the kidneys?
In humans, the kidneys are two bean-shaped organs located in the upper back on either side of the spinal column.