Why do cells need cell divsion for replacement and repair?
All cells have a limited lifespan, or can become damaged, so these cells must make copies of themselves before they die to replace the lost, or heal the damaged.
Why do cells need cell division for growth?
New cells are needed as organisms grow, as there are limitations to their size.
Through imaging technologies (X-Ray, ultrasound, MRI etc.) or by examining the cells (remove suspected cancer cells and observe under microscope).
How can you treat cancer?
surgery (physically remove cancerous tissues)
chemotherapy (drugs to slow/stop cancer cells)
radiation (cancer cells easily damaged by ionizing radiation)
biophotonics (beams of light to detect/treat cancer)
What are stem cells?
Cells before the specialize.
How are specialized cells different?
Have different structural and functional differences, as certain genes have been activated and deactivated by different proteins being produced.
What are the six levels of structure in biology?
1. Atoms (ultramicroscopic building blocks of matter)
2. Molecules (2 or more atoms combined)
3. Cells (association of molecules, growth/devolpment)
4. Tissues (cells that perform the same function working together)
5. Organs (tissues work together to perform specialized anatomical and physiological functions)
6. Organ systems (several organs with complementary functions)
What molecules are examples of those important to the body?
water
sodium chloride
proteins
carbohydrates
lipids (fats)
What is epithelial tissue?
Tissue that covers the body surface, lines the body cavities, forms major parts of glands. Lack of blood supply is made up by connective tissue underneath.
What are the five functions of epithelial tissue?
Protecting the inner tissues from dehydration, irritation, toxic substances and trauma
Absorbing gases and nutrients such as in the lungs and the digestive tract
Transporting nutrients, fluids, mucus, and other particles of matter
Secreting cell products such as enzymes, sweat and hormones
Sense the environment (ears, nose and taste buds)
What is connective tissue?
A tissue that provides support and protection to the body, and can also transport materials and store things.
What are the four types of connective tissues?
1. Connective tissue proper
2. Cartilage
3. Bone
4. Blood
What is connective tissue proper?
Consists of adipose (fat), elastic and collagen. Found between and around muscles, make up tendons and ligaments, beneath the skin and in the walls of many organs.
What is cartilage and what three things does it include?
supporting tissue with tensile strength (firm yet rubber-like), no blood vessels
1. Hyaline (ends of bones, external ear, nose, larynx, trachea and bronchi-weakest and most common)
3. Fibrous (skull bones, between disks of spinal cord - strongest)
What is bone?
The hardest connective tissue. Consists of cells, collagen fibres, and dense substances made of calcium and phosphate. Rich in blood supply, also the site of blood cell formation in the blood marrow.
What is blood?
A specialized connective tissue whose base substance is a fluid. The blood transports nutrients, gases and waste products around the body.
What are the four types of tissues found in the body?
Epithelial
Connective
Muscle
Nervous
What is muscle tissue?
A tissue with the ability to exert force and produce movement when it contracts. The cells are enlongated so they will not be damaged during the contractions and relaxtions.
What are the three types of muscle tissue?
1. Skeletal (attached to bone ie. voluntary muscle)
2. Smooth (walls of digestive, urinary, circulatory and respiratory tracts ie. involuntary muscle)
3. Cardiac (found in heart ie. involuntary muscle)
What is nervous tissue?
A tissue that recieves information from the outside world and transports the electrical stimulus to the brain, where it is interpreted so the body can react.
What is the digestive system?
An organ system that takes in food, break it down to recieve nutritional components, then excretes the remaining waste.
What are the four processes in the digestive system and where do they occur?
1. Ingestion (intake of food)
2. Physical digestion (mechanical breakdown of food - teeth, tounge and stomach)
3. Chemical digestion (food particels broken down by action of enzymes so nutrients can be absorbed - mouth, stomach, small intestine)
4. Egestion (elimination of waste)
What are the food components broken down during chemical digestion?
Proteins into amino acids
Carbohydrates into glucose
Fats into fatty acids and glycerol
What is bag digestion?
Food is ingested through an opening and moves into a sac that conatins digestive enzymes. The waste is excreted through the same opening.
What is tube digestion?
This involves a loong tube with two opening, one at either end.
What are the three types of tube digestion?
Storage system
Herbivore system
Carnivore/Omnivore system
What is a storage system digestion?
A storage sack, called a crop, stores large amounts of food for later breakdown and gradual digestion near the beginning of the digestive tract. eg. Birds and Worms
What is a herbiove system digestion?
Since herbivores consume plant matter that contains cullulose, which is hard to digest, they need a longer digestive tract to allow for sufficient opportunity for absorption.eg. Cows
What is a ruminant?
An animal that has a digestive system that allows for otherwise indigestible foods to be digested through a herbivore system. The food is repeatedly regurgitated and rechewed as "cud", then reswallowed and furth digested by specialized microorganisms in the vumen.
How does a cow's stomach work?
There are four compartments.
1. Rumen - specialized microorganisms are here to digest food (largest compartment)
2. Reticulum - "Honeycomb"
3. Omasum - absorb water and nutrients
4. Abomasum - "true stomach", like human stomach
What is a carnivore/omnivore system?
A complex digestive tract made up of 4 different tissue types.
What is mucosa?
The epithelial lining of the digestive tract that consists of different mucus, enzyme, and hormone secretin cells and absoprtive cells.
What is the submucosa?
Part of the digestive tract that consists of connective tissues, blood vessels, nerves, and lymphatic vessels.
What is the muscular layer of the digestive tract?
Circular layer of smooth muscle that forms a ring around the tube to contact the lumen.
What is the serosa?
Layer of connective tissue that covers the outside of the digestive tract, seperating it from the rest of the abdominal organs.
What is the visceral peritoneum?
The serosa of the digestive tract.
What are the six parts of the human digestive route and their functions?
1. Mouth (physical and chemical digestion of food - process of mastication [mechanical breakdown of food])
2. Esophagus (muscular tube that connects the pharynx to the stomach, chewed food moves through ripples called peristalsis)
3. Stomach (stores and releases food into intestines in regular intervals, mechanical and chemical digestion using hydrochloric acid, turns food into chyme)
4. Small Intestine (major site of digestion and absoption)
5. Large Intestine (absorb water from waste, hold and compact unabsorbed waste, Vitamin K is produced here)
6. Accessory Organs
What acid does the stomach use?
Hydrochloric Acid
Name the three parts of the small intestine and their functions.
1. Duodenum (recieves secretions from pancreas and the liver for final chemcial breakdown)
2. Jejunum (first part of the absorption process)
3. Ileum (completes the absorption process)
Name the seven parts of the large intestine.
Cecum, Ascending/Transverse/Descending/Sigmoid Colon, Rectum, Anus
Name the three accessory organs of the digestive system.
1. Liver
2. Gall Bladder
3. Pancrease
What is the function of the liver?
Produce bile, which is highly basic and neutralizes the acidic chyme from the stomach
Break down fats
Regulate the level of glucose in the bloodstream
Remove ammonium
Produce cholestrol which is used to rebuild cells
Produce blood-clotting chemicals
What is the function of the gall bladder?
Stores some of the bile that the liver produces, and allows it to drip into the duodenum when food passes through.
What is the function of the pancreas?
Produce bicarbonates to help control the pH level in the duodenum
Produce hormones, such as insulin, in repsonse to sugar levels in the blood
Produce enzymes (major task or pancreas)
What is the function of the circulatory system?
Transport substances around the body, including carrying nutrients to the cells and waste away
Regulate the body's temperature
Transport disease-fighting white blood cells
What are the three components of the circulatory system?
1. Blood
2. Tubes and vessels
3. The heart
What are the four components of blood, their functions and their percentage of make-up of blood?
1. Red blood cells (carry oxygen) - 45%
2. White blood cells (infection-fighting cells) - <1%
3. Platelets (initiate the clotting process) - <1%
4. Plasma (liquid part of the blood which transport the various cells) - 55%
What are the three components of tubes and vessels in the circulatory system and their functions?
1. Arteries (thick, muscular, carry blood away from the heart)
2. Veins (less muscular, larger in diameter, carry blood toward the heart)
3. Capillaries (tiny blood vessels, thin walls, red blood cells move through tubes one at a time, supplies each part of the body with a network of capillaries)
Describe the heart, how it works, and its function.
send blood throughout body
pacemaker controls beating of heart through electrical signals
pump consists of chamber (atria and ventricles)
Describe an open circulatory system.
Blood is dumbed into the body cavity from the arteries. Later, the pressure increases and pushes the blood back into the veins. (eg. mollusks, anthropads, insects)
Describe a closed circulatory system and name the three types.
All blood vessels are connected, keeping the fluid inside the tubes.
1. Single Circulation
2. Double Circulation - Three Chambered Heart
3. Double Circulation - Four Chambered Heart
Describe how a single circulation circulatory system works.
involves a two chambered heart (one atrium and one ventricle)
eg. fish
Describe how a double circulation, three chambered heart, circulatory system works.
oxygen rich blood from the lungs goes to the left atrium
oxygen poor blood from the body goes into the right atrium
both atria empty into one common ventricle, blood mixes
eg. Frog
Describe how a double circulation, four chambered heart, circulatory system works.
Oxygenated blood pumps from the left atrium to the left ventricle
Deoxygenated blood pumps from the right atrium to the right ventricle
eg. Humans
What is the function of the respiratory system?
Provide the oxygen needed by the body and remove the carbon dioxide produced.
Explain how the gas exchange of the respiratory system occurs.
Gas molecules dissolved in a fluid before they can pass through a thin, mosit membrane through the process of diffusion. Maximum surface area is attained in the membrane.
What two processes involved in the respiratory system?
1. Breathing (mechanical process by which gases are exchanged between the organism and the environment)
2. Respiration (cellular process that takes place in the mitochondria of every cell in the body
What are the two types of gas exchange systems?
1. Flow through
2. In and out
Explain a flow through respiratory system.
The medium (air or water) comes in through one opening, flows through a channel in the body, and exits via a second opening. eg. Fish (indirect)
Explain an in and out respiratory system.
The medium carrying the gases enters through one opening, travels along a path to the gas exchange surface, and leaves the body through the same opening.
Explain a simple in and out respiratory system of an earthworm.
The gas exchange occurs by diffusion through the epidermal layer, which is kept moist by mucus secretions. Blood cappilaries are found in the epidermal layer so the gases can diffuse directly through the skin into the blood stream.
Explain a complex in and out respiratory system.
This system uses internal tubes and sacs through which gases are either diffused or are actively pumped, delivering oxygen directly to tissues via the trachea.
Explain the respiratory system of a human.
Air enters through the mouth or nostrils, travels down the trachea to the bronchi, which seperates into brochioles. This leades to the alveoli, where the actual gas exchange occurs.
What is the function of the nervous system?
It is the communication and control system of the body that links the external environment and the body together, allowing the organism to react appropriately.
What are the two parts to the human nervous system?
1. Central nervous system (brain and spinal cord)
2. Peripheral nervous system (nerves to the organs and cells)
What is the function of the peripheral nervous system?
It relays information from the internal and external environments to the brain. It carries messages from the brain to the body organs for appropriate responses.
What are the three different groups of nerves?
1. Motor Nerves (nerves that control voluntary muscles such as skeletal muscles)
2. Sensory Nerves (nerves that relay information from the sensory organs and touch receptors to the brain)
3. Nerves that control and regulate involuntary functions such as breathing, heart rate, and digestion
Explain the make up of a neuron.
Dendrites (short, branching extensions of the cell body that recieve information from other cells)
Cell body (recieves the information from the dendrites, and the nucleus determines if the signal should continue)
Axon (long thin path lead from the cell body to the axon terminals where the transmitted signal release a neurochemical)
Explain how nerve cells work.
A nerve signal is conducted in one direction along the nerve cell, where a chemical is diffused accross the synapse, to stimulate receptors of the next nerve cell. To speed up the movement of the signal, the axon is covered with a fatty material called myelin, which acts as insulation ensuring the electrical signals continues along its correct path.
What is the function of the muskoskeletal system?
This system is responsible for supporting the body, protecting vital organs, and making movement possible.
How many bones does the human body have?
206
What type of tissue is the human skeletal system made up of, and what are the three components?
Connective tissue (bone, ligaments and cartilage)
What are the five types of bones in the human body?
Tough, elastic connective tissues that hold the bones together at the joints. They are composed of long, collagen fibres.
What is cartilage?
Dense, connective tissue that is found between the bones to provide a strong, flexible support system. This tissue makes up the disks between the vertebra and the pads between the bones.
How does the skeletal and muscular systems work together?
Sketelal muscles are made up of overlapping muscle fibres, that contract and cause the overlap to increase, shortening the muscle and pulling on the bone. Muscles are attached to a tendon which is attached to the bone.
What type of tissue type/types is in the layers of the tube in a carnivore's tube digestive system?
E) All of the above
What is the difference between veins and arteries.
Veins are larger in diameter
Arteries are more muscular
Veins are thinner
Arteries carry blood away from the heart, veins carry blood toward the heart.
True or False: In birds, the oxygen diffuses into the blood directly from the air saces.
False
What tissue connects bone to the muscle?
Tendons
What component of blood is responsible for repairing blood vessels that are damaged?
Platelets
Where are the tricuspid and bicuspid valves?
Tricuspid - between the right atrium and ventricle
Bicuspid - between the left atrium and ventricle
Define the term diffusion.
Diffusion is the transportation of gases through a semi-permeable membrane from an area of high concentration to an area of low concentration.