Reviewer in Science
by: Francesca Guzman
Science - a search for knowledge or truth
Technology - the application of scientific knowledge
Branches of Science
a. Pure Science - systematic study of natural or physical phenomena
b. Applied Science - search for practical uses of scientific knowledge
3 Main Divisions
1. Physical Sciences - study of non-living matter
a) Chemistry - deals with the study of composition, structure, form and the chemical properties of matter.
b) Physics - deals with the study of matter and energy including light, sound, electricity, magnetism, radiation and motion.
2. Earth Science - deals with scientific study of the earth
a) Geology - involves the study of the origin, evolution and structure of the earth's crust.
b) Palaeontology - scientific study of prehistoric life, based mainly on fossils of animals and plants
c) Meteorology - study of the atmosphere that focuses on weather processes and forecasting
d) Seismology - study of earthquake and the movements of the waves through earth
e) Astronomy - study of celestial bodies
3. Life Sciences - deals with the study of living organisms
a) Biology - study of plants and animals
b) Botany - deals with the study of plants
c) Zoology - study of animals, their form and structure
d) Ecology - deals with the study of living organisms with each other and their interaction with their surrounding
e) Genetics -study with the genetic make up of living organisms
Local Scientists
1) Julian Banzon - Grand Man of Chemistry
works on fuels and on local materials
2) Fe Del Mundo - Grand Dame of Philippine Pediatrics
research on viral disease
3) Dolores Ramirez - Biochemical geneticist and plant breeder
work on cytogenetics
4) Hilario Lara - Father of Modern Public Health
Pioneering work on and control of diseases
Foreign Scientists
1) Isaac Newton - Law of motion
2) Galileo Galilee - discovered the use of telescope
3) Albert Einstein - Law of relativity
4) Michael Farraday - Law of electrolysis and discovered electromagnetic induction
5) Gregor Mendel - Law of heredity
6) Marie Curie - investigation of radioactivity
7) Louis Pasteur - invented the process of pasteurization, founded the science of microbiology, and developed vaccines
8) Alessandro Volta - pioneering work in electricity, devised electrophorus
Integrated Science Process Skills
Hypothesis - a tentative answer or explanation of something
Variables - factors or elements in the experiment that affect the result
Interpreting Data - to explain the meaning of something
Laboratory Tools
For heating
Bunsen burner, tripod, wire gauze, Iron stand with iron ring
Instruments used for measuring and holding liquids
Erlen meyer flask, volumetric pipette, filtering flask, Florence flask, watch glass, test tube, volumetric flask, reagent bottle, graduated cylinder
Transferring liquids
Filter funnel and dropper
Instruments used in Measuring Solids
Platform Balance, Spring balance, Triple Beam Balance
Compound Microscope
· A microscope - device that gives an enlarge picture of tiny objects.
· Anton van Leeuwenhoek, Dutch naturalist and made the first microscope
· It has a magnifying system, mechanical and a light system.
A. Mechanical Parts
1) Base - it serves as the structure on which the microscope stands.
2) Arm - connects the base and the body tube together and serve as the handle.
3) Stage - it is where the specimen is placed
4) Stage clips - holds the slide securely on the stage
5) Body tube - holds the objectives, connects ocular to objectives.
6) Coarse Adjustment knob - use to locate the specimen to lower & raise the body tube
7) Fine Adjustment knob - moves the body tube slightly when focusing under HPO and other high powered lenses
8) Draw tube - supports the ocular, connects to the body tube and ocular eye piece.
9) Revolving Nosepiece - used to change objective from LPO to HPO or vice-versa
B. Magnifying Parts
1) Eyepiece/ocular - a detachable cylinder where one peeps to see the specimen.
2) Objectives - usually an ordinary laboratory microscope has 2 or 3 objectives attached to the revolving nosepiece
a) Low power objective (LPO) - used to observe the general outline and locating various parts of the specimen. Focus using the coarse adjustment knob.
b) High power objective (HPO) - used to study detailed parts of the specimen. Focus using the adjustment knob.
C. Light System
1) Mirror - used to reflect light through the object, lenses into the eye.
2) Diaphragm - controls the amount of light going to the specimen.
Functions of the Circulatory System
1. to transport materials - nutrients and oxygen
2. to remove waste materials
3. to regulate body temperature
4. to fight diseases
Parts of the Human Circulatory
The heart
· It has four chambers
left and right atrium - the collecting chambers; receive blood from the veins
left and right ventricle - the pumping chambers; pump blood out of the heart through the arteries
The septum - a heart wall that seperates the left side from the right side of the heart
The heart's right side pumps deoxygenated blood from the body to the lungs. The heart's left side pumps oxygenated blood away from the heart
Types of Valves in the heart
Valves - keep blood flowing only in one direction, from atrium to the ventricles
1. Tricuspid valve - valve between the right atrium and right ventricle
2. Bicuspid valve - valve between the left atrium and left ventricle
3. Semilunar valve - located between the ventricles and arteries
The Blood and Blood Vessels
Blood vessels - structures through which blood moves
a) Artery - thick-walled, elastic, no valve
- carries oxygen - rich blood away from the heart
Aorta - the largest artery in the human body
Arterioles - the smallest artery
b) Vein - thin-walled, elastic, with valves
- carries deoxygenated blood back to the heart
Vena Cava - largest vein
Venules - smallest vein
c) Capillary - with very thin walls, no valve
- the smallest blood vessels
- carries blood to the body cells
The Blood
· the liquid that is constantly flowing throughout our body
· transport water, oxygen, nutrients, salts, hormones, and other substance that sustains life
· removes waste products of metabolism
Blood Components
Blood Cells : Solid components of Blood
1. Red blood Cells or erythrocytes (RBC)
· Carry oxygen throughout the body
· most abundant cells in the body
· It has hemoglobin - a protein that is responsible for carrying oxygen and gives blood the red color
· Life span : 120 days
2. White Blood Cells (WBC) or Leukocytes
· the defense team protect the body against infection
Types of WBC
a) Phagocytes - kill bacteria and other organisms by engulfing them
b) Lymphocytes - produce antibodies, kill bacteria directly or make them harmless
3. Platelets
· The blood clotter
· smallest blood cells
· contain protein needed for blood clotting to prevent excessive loss of blood
4. Blood Plasma : Liquid Component of the Blood
· Transports blood cells
· contains 90% water and 10% dissolved materials (glucose, proteins, ions, hormones, salts, etc.)
Four major blood types
A, B, O and AB
O - universal donor: the person can donate moderate amount of blood to people of any blood type
AB - universal recipient. can receive moderate amounts of blood type
The Blood Circulation
Blood circulation - the movement of the blood as it distributes food and oxygen to the body cell and remove waste materials
Pulmonary circulation - the pathway of blood from the heart to the lungs and back to the heart
Systematic circulation - the pathway of blood from the heart to the different parts of the body and then back to the heart
Pulmonary circulation
Blood from all over the body → Superior Vena Cava/Inferior Vena Cava → Right Atrium → Right Ventricle (pulmonary arteries) → lungs → Left atrium (pulmonary veins)
Systematic Circulation
Left atrium (Bicuspid/ Mitral valve) → Left ventricle (Semilunar valve) → aorta → arterioles → capillaries of the different organs of the body
Common Ailments of the Circulatory system
1. Atherosclerosis - thickening of the walls of blood vessels
2. Arteriosclerosis - the hardening of the arteries. Major artery lose their elasticity when cholesterol and other fatty deposits build-up at the innerwall
3. Hypertension - an increase of blood pressure which may be due to high cholesterol, heredity, excessive intake of alcohol and fatty foods, and stress.
4. Stroke - caused by a lack of blood flow to part of the brain caused by blood clue in one of the artery or rupture of an artery wall.
5. Thrombosis - an abnormal blood clotting within the blood vessels blocking the flow of blood. It can lead to fatal heart attack.
6. Anemia - person's number of healthy red blood cells or hemoglobin decreases in the body.
a. Iron deficiency anemia - occurs because the marrow fails to produce sufficient red blood cells
b. Aplastic anemia - due to inadequate production of red blood cells in the bone marrow due to long exposure to toxic chemicals like benzene, lead or arsenia
c. Sickle - cell anemia - genetics disorder caused by defective gene that produces abnormal form of hemoglobin
7. Leukemia - a form of blood cancer characterized by uncontrolled increase in the number of defective white blood cells
8. Aneurysm - a balloon-like swellings that results in the weakening of the aortic walls.
9. Hemophibia - the inability of blood to clot leading to hemorage or excessive bleeding, even from minor injuries
The Male Reproductive System
All organisms produce offspring (through the descendant of a person or an animal) through the process of reproduction
Reproduction - the biological process by which offspring/organisms are produced. The fundamental feature of all known life.
Through reproduction, species of the organisms can survive and pass on its traits to the next generation.
It involves 2 type of cells called gametes, the sperm cells from the male and egg cell from the female.
1. Testes
· primary sex organ
· produces sperm and
· produces male sex hormone (testosterone - responsible for the development of secondary sexual characteristics during puberty)
2. Semineferous tubules
· produce the sperm cell that eventually mature through the process of spermatogenesis
3. Interstitial leydig cells
· specialized connective tissue found in between the lobules of testes
· produce the male sex hormone testosterone
4. Epididymis
· where sperm cells mature and develop their swimming capability.
5. Vas deferens - (Ductus deferens)
· a muscular tube that transport sperm cells and semen.
6. Urethra
· where all fluids are released
7. Seminal vesicle
· produces an alkaline substance that is the viscous component of the semen rich in nutrients for the sperm cells
8. Penis
· external male organ
9. Prostate gland
· also secretes an alkaline fluid that is part of the semen; it's fluid plays a role in activating the sperm cells to swim
10. Cowper's gland
· located beneath the prostate gland
· secretes a thick viscous alkaline muscles
· cleans the urethra of any acidic urine.
Female Reproductive System
1. Ovary -
v primary sex organ
v contains immature egg cells (oocyte - found inside the ovarian follicles)
v produces mature egg cells during ovulation
v mature follicle with a mature egg inside called grafarian follicle.
2. Fallopian tube
v transports ova from ovary to the uterus
v where fertilization occurs
v fertilization - union of the egg and sperm cell
3. Fimbriae
v catches the mature egg once it is released from the ovary
4. Uterus (womb)
v site of menstruation
v where egg is implanted after fertilization
v where fetus develops
a. Endomentrium - innermost layer
- fertilized egg burrows during implants
b. Myometrium - middle layer
- composed of smooth muscles when contracts and pushes the baby out of womb during delivery
c. Perimetrium - outermost layer
5. Vagina
v lower portion of the birth canal
v passageway of menstrual discharge
Central Nervous System
Functions of the Nervous System
v It is our body's command system
v It controls how we respond to changes inside and outside the body
v It is divided into central nervous system and peripheral nervous system
v It includes the following parts: brain, spinal cord, network nerves, and specialized cells in the sense organ
v Central Nervous include the brain and spinal cord
v Peripheral Nervous System included the network nerves, and specialized cells in the sense organ.
Central Nervous System
1. Brain: The Control Center
> the largest organ of the nervous system that acts as the control system of the body> it is protected by the skull, soft tissue, called meninges, and a cushion of fluid
It has 3 parts
1) Cerebrum
· largest region of the brain
· It controls the voluntary activities of the body like thinking, solving problems and remembering details
· It is divided into the left and right hemisphere and different bone
2) Cerebellum
· the second largest region of the brain
· it is located behind the cerebrum
· it controls muscles coordination of our body like walking and writing
3) Brain stem
· connects the brain to the spinal cord
· It controls the involuntary muscles of the body and coordinates functions like breathing and beating of the heart
· Consists of the medulla oblongata, pons and midbrain
The upper end of the brain stem is the hypothalamus and the thalamus
Hypothalamus - regulates functions like thirst, appetite, and sleep patterns. It also regulates the release of hormones from pituary gland
Thalamus - processes and coordinates sensory messages such or touch, received from the body
Spinal Cord -
· relays information between the brain and the rest of the body
· controls the actions that do not involve the brain such as reflexes
Reflex actions are the automatic, involuntary reaction to a stimulus.
Ex. sneezing, blinking of eyes when cornea is touched, and when jumping when frightened
Nervous System: Neuron
1. Dendrites
· receive information from a receptor or another neuron and then transmit the message to the cell body
2. Cell body - (also called soma or cyton)
· sends or receives impulses to or from other cells
3. Axon - conducts the information away from the cell body
Myelin Sheath is a fat-like substances that wraps around the axon. Myelinated axons transmit nerve impulses faster than these than are nor.
3 types of Neuron
1. Sensory Neurons - carries messages from their receptor organs ( skin, eyes, nose, and tongue) to the nerve centers (brain and spinal cord)
2. Motor Neurons - receives information from the nerve centers and transmit it to the effect or organs (muscles or glands)
3. Interneurons - process and carry information between the other neurons
The nervous system sends and receives messages from the point of stimulus to the response made on that stimulus
A stimulus is any change in the internal or external environment of organism
Sensory nerve receive information from our senses, then they send this information to our brain, via the spinal cord for processing. The brain then sends the information to the motor nerves telling them what to do. The muscles will respond accordingly
Ex.
1. Stimulus hand touches the side of a cup of hot chocolate
2. Sensory nerves the messages travels through the sensory nerves of the hand then to the spinal cord that sends it to the brain
3. The brain processes the information and sends an appropriate response to the motor nerves of the hand.
Common Ailments in the Nervous System
1. Hydrocephaly - an extreme enlargement of the head in newborns or infants due to overproduction of the watery fluid within the spaces of the brain that cannot flow normally.
2. Meningitis - an inflammation of the membranes covering the brain and the spinal cord due to bacteria or virus
3. Parkinson's disease - characterized by slow movement, extreme rigidity of voluntary muscles, hand tremors, frozen facial expression and progressive weakness.
4. Poliomyelitis/Infantile Paralysis - an acute infection and destruction of motor neurons in the brain
5. Multiple Sclerosis - marked by loss of muscle control due to hardening of nerve tissues in the brain or spinal cord
6. Cerebral Palsy - characterized by weakness in certain muscles (legs)
7. Alzheimer's disease - characterized by failing memory and impaired through processes
8. Concussion - an injury that results in temporary loss of brain function
9. Paralysis - an injury to the spinal cord that results loss of ability to muscles
10. Migraine - severe headache which is often limited to just one side of the head followed by unusual sensations
No comments:
Post a Comment