Science exam Flashcards
Name all parts of a neuron
Dendrites, cell body, nucleus, Myelin sheath, axon, axon terminals and synapse
Dendrite function
Receives chemical messages from connecting neuron.
Cell Body Function
Maintains neurons structure and brings energy to the neuron.
Nucleus Function
The nucleus controls and regulates the activities of the cell (e.g., growth and metabolism) and carries the genes, structures that contain the hereditary information.
Myelin Sheath function
A fatty layer that helps insulate the axon, and allows the electrical signal/impulse to travel much more quickly.
Axon Function
Conducts nerve impulses away from the cell body (electrical impulses)
Axon terminals Function
Releases the message across the synapse to adjacent neurons. (Chemical messages)
Synapse Function
Small gap between two neurons, also referred to as synaptic gap
5 steps in an involuntary stimulus response
Stimulus
Receptor
Relay neuron/interneuron
effector
response
5 steps in a Voluntary Stimulus response
Stimulus
Receptor
Control center
effector
response
Explain why it is important for a reflex action to be faster.
It is important because a reflex reaction does not happen consciously and only happens when you are in danger of something. That is why it is important that it is fast.
Name three causes of Spinal cord injury.
Road traffic incident
Falls from a height
Sporting injuries
Name three consequences of a spinal cord injury.
Paralysis
Numbness
Difficulty with balance
Name all eight glands in the endocrine system.
Pineal gland, pituitary gland, parathyroid, thyroid gland, pancreas, ovaries and testes
Pineal gland function
The main function of the pineal gland is to receive information about the state of the light-dark cycle from the environment and convey this information to produce and secrete the hormone melatonin.
Pituitary gland function
The main function of your pituitary gland is to control the functions of other glands in the endocrine system.
Parathyroid function
Release of calcium by bones into the bloodstream. Absorption of calcium from food by the intestines. Conservation of calcium by the kidneys. Stimulates cells in the kidney to transforms weaker forms of vitamin D into the form that is strongest at absorbing calcium from the intestines.
Thyroid gland function
The thyroid gland secretes hormones to regulate many metabolic processes, including growth and energy expenditure. If the thyroid gland is overactive or sluggish, the metabolism will be affected, leading to a variety of symptoms that are easily misdiagnosed.
Adrenal gland function
Adrenal glands produce hormones that help regulate your metabolism, immune system, blood pressure, response to stress and other essential functions.
Pancreas function
During digestion, your pancreas makes pancreatic juices called enzymes. These enzymes break down sugars, fats, and starches. Your pancreas also helps your digestive system by making hormones. These are chemical messengers that travel through your blood.
Ovaries function
They produce eggs for fertilization and they make the hormones estrogen and progesterone. An ovary releases an egg around the middle of your menstrual cycle (around day 14 of a 28-day cycle) in a process called ovulation.
Testes function
The testes are responsible for making sperm and are also involved in producing a hormone called testosterone. Testosterone is an important hormone during male development and maturation for developing muscles, deepening the voice, and growing body hair.
Define hormones.
Hormones are your body’s chemical messengers produced by the body to control and regulate certain
cells/organs.
Define gland
An organ that makes substances such as hormones.
Define Homeostasis
The maintenance of a stable internal environment within your body
Define negative feedback
A response to a stimulus that counteracts the change to return to the set point.
Describe four key differences between the nervous and endocrine systems.
Nervous system uses electrochemical messages- endocrine uses chemical messages(hormones)
Uses nervous system-uses circulatory system
Activities are localized-Activities are widespread
Fast acting response-slow acting response
List two hormones that are released in the endocrine system
Insulin, produced by the pancreas regulates blood glucose levels by decreasing them. From increasing glucose uptake from cells. Glucagon, produced by the pancreas regulates blood glucose levels. By increasing glucose from body stores.
Name and describe the role of the master gland.
It is the pituitary gland and it’s role is to control the functions of many other glands in the endocrine system
Identify the real part of the brain that maintains homeostasis and list three functions.
Main connection between nervous and endocrine system
Maintaining homeostasis through releasing hormones
Monitors the body through circulatory and nervous system
Write balanced chemical equation for photosynthesis.
6C02+6H20=C6+H12+602
Identify the reactants in aerobic cellular respiration
Glucose, C6H1202
Oxygen, O2
Identify the products in aerobic cellular respiration.
Carbon dioxide, CO2
Water, H20
Differences and similarities between aerobic cellular respiration and anaerobic cellular respiration.
requires oxygen-absence of oxygen
requires glucose-requires glucose
more energy produced-less energy produced
products H20, CO2-Animals, lactic acid. Plant’s, ethanol=CO2
State the normal temperature of a human and why we need to maintain it.
36-37 degrees Celsius. We need a stable temperature for the enzymes in our body to function effectively and organs to continue functioning.
Explain how body reacts if it goes above normal temperature.
Sweat glands release sweat, blood vessels dilate
Explain how body reacts if it goes below normal temperature.
Blood vessels constrict, muscles shiver to generate heat, goosebumps occur to trap air layer near skin.
Explain stimulus response when blood sugar levels increase.
S- increase in blood sugar levels
R- pancreas cells
cc- hypothalamus
E- insulin produced so that liver takes up more glucose
R- blood sugar levels drop to normal levels
Define disease.
An illness that prevents a part of the human body to function normally.
Name four pathogens or microbes that cause disease.
Viruses- herpes, flu
Bacteria- plague
Fungi- ringworm, athletes foot
Parasites- lice,
Explain what a vector is
A vector is a living organism that transmits an infectious agent from an infected animal to a human or another animal.
Describe how granite is formed?
Formed from magma solidifying underground
Describe how basalt is formed?
Lava solidifying on the Earth’s surface.
Sandstone is a sedimentary rock, describe how it is formed.
Weathering of igneous or metamorphic rock
Erosion breaks down rocks into sediment
Deposition of layers
Compaction of rocks pressed together
Cementation forms the sedimentary rock
Marble is a metamorphic rock formed from limestone, describe how it is formed.
Marble is formed when limestone is subjected to intense heat and pressure over time.
Describe continental drift. Give three pieces of evidence for it.
It is the theory that the Earth’s crust is divided up into moving plates.
Continents fit into together like a jigsaw puzzle.
Same plant and animal fossils found across different continents
Rock layers of similar material across different continents
Explain how convection currents cause tectonic plates to move.
Crust moves the same direction as current.
Hot magma rises to the crust, as it rises it cools and sits back down creating convection currents.
Source of heat for convection currents.
The source of heat comes from the core in the form of radioactive decay.
Explain Transform boundaries.
Plates slide past one another causing earthquakes.
Explain divergent boundaries.
Plates move away from each other causing mid ocean sea ridges, rift valleys and volcanoes.
Explain convergent boundaries.
Plates move into one another cause one to go above another plate. Which forms subduction zones. This causes ocean trenches, volcanoes and earthquakes.
Describe each layer of the earth
inner core, outer core, mantle, crust
Describe the focus point in a earthquake.
This is the point below the earth’s surface where the earthquake originates.
Describe the epicentre in an earthquake.
It is the point directly above where the focus is but on the earth’s surface.
Describe the fault in an earthquake.
A fracture in the rocks along with the movement that causes an earthquake.
How many times more powerful is an 8 on the richter scale compared to a 9.
Every digit means it is ten times more powerful.
Describe a real life example of a transform boundary.
The San Andreas fault along the coast of California.
Describe a real life example of a convergent boundary
Indo-Australian plate into the Eurasian plate near Indonesia and Sumatra.
What are the three waves recorded by a seismograph.
Primary waves, secondary waves and surface waves.
Describe all the waves meaning.
Primary waves are the first waves.
Secondary waves are body waves that travel through the the Earth’s inner layers.
Surface waves travel on the surface and cause the most damage.
Describe how a tsunami is created.
Meteor hitting the ocean
Undersea volcano
Erosion or avalanche
Converging plates
Describe the mantle plume in a hotspot.
A mantle plume is the upwelling of abnormally hot magma. This causes the crust to weaken and create a hotspot where lava is released in the form of volcanoes.
Suggest two examples of real life hotspots
Hawaii, Galapagos islands
State properties of all subatomic particle.
Protons- positive charge, located in nucleus, relative mass is 1 AMU
Neutrons- neutral charge, located in nucleus, relative mass is 1 AMU
Electrons- Negative charge, Orbiting around nucleus, relative mass is negligible
Maximum number of electrons each shell can hold.
first shell- 2
second shell- 8
third shell- 18
last shell- 32
Maximum number of electrons each shell can hold.
first shell- 2
second shell- 8
third shell- 18
last shell- 32
List three types of radiation and their properties.
Alpha, atomic number is 2, mass number is 4, charge is plus 2, Ionizing power is high, penetrating power is low
Beta, no atomic number, no mass number, plus or negative charge, medium ionizing power, medium penetrating power
Gamma, no atomic number, no mass number, negative charge, low Ionizing power, high penetrating power.
Describe what a half life is?
A half life is a measure of the decay of a radioisotope.
What happens to atoms during radioactive decay.
They release ionizing radiation energy.
What is the aim of a scientific report.
An aim is a single statement that describe the purpose or reason for why we are conducting an experiment. An aim should be brief and concise. It should state the purpose of the experiment without providing a prediction.
What is the hypothesis of a scientific report.
The hypothesis is often written using the words “IF” and “THEN.” For example, “If I do not study, then I will fail the test.” The “if’ and “then” statements reflect your independent and dependent variables. The hypothesis should relate back to your original question and must be testable.
What is the independent variable in a scientific report.
The independent variable is the one that is changed by the scientist. To insure a fair test, a good experiment has only ONE independent variable.
What is the dependent variable in a scientific report
The dependent variable is the variable that is being measured or tested in an experiment. 1 For example, in a study looking at how tutoring impacts test scores, the dependent variable would be the participants’ test scores, since that is what is being measured.
What is the controlled variable in a scientific report?
A control variable is anything that is held constant or limited in a research study. It’s a variable that is not of interest to the study’s aims, but is controlled because it could influence the outcomes.
