Biology CST Review

EcologyPhysiology

ECOLOGY

How organisms relate to each other and to their surroundings.

The total number of different species to inhabit one

area. The more the species, the more will survive in case of disasters to the habitat.

Biodiversity6a: Students know biodiversity is the sum total of different kinds of organisms and is affected by alterations of habitats.

Natural ecosystems can undergo many

alterations and can make necessary changes to accommodate them. Sometimes, alterations are too great and nature cannot recover. Climate – ice age, drought Human activity – pollution, destruction Nonnative species – organism that is not native to

area, usually has no natural predators & grows unchecked

Population size – too many deaths or births or migration

Ecosystem Changes6b: Students know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of nonnative species, or changes in population size.

Succession

Order of life inhabiting an area – always smallest to biggest

lichen

6b: Students know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of nonnative species, or changes in population size.

Population is the total amount of one species

in a given area. The change in the size of the population is determined by four factors: Birth rate – number of organisms born & surviving Death rate – number of organisms dying Immigration – number of organisms moving INTO

area Emigration – number of organisms moving FROM

area

Population Size6c: Students know how fluctuations in population size in an ecosystem are determined by the relative rates of birth, immigration, emigration, and death.

Population Size

BIRTHS

Immigration DEATHS

Emigration

Biogeochemical Cycles6d: Students know how water, carbon, and nitrogen cycle between

abiotic resources and organic matter in the ecosystem and how oxygen cycles through photosynthesis and respiration.

Food Chains & Webs What eats what?

Producers (plants) Consumers (animals – herbivores,

carnivores, omnivores) Decomposers (bacteria, fungi) – eat

any dead organism

Producers, Consumers, Decomposers6e: Students know a vital part of an ecosystem is the stability of

its producers and decomposers.

100%

Organisms only obtain 10% of energy from what they eat. 90% is released as heat.

Source of all energy is the sun!

Energy Pyramid6f: Students know at each link in a food web some energy is stored in newly made structures but much energy is dissipated into the environment as heat. This dissipation may be represented in an energy pyramid.

10%

1%0.1%

0.01%

0.001%

BIOTECHNOLOGY

Manipulating the genes of an organism to produce different results.

Humans directly manipulating an organisms genome, usually for the benefit of people Ex: manufacturing human insulin for people with

diabetes Ex: adding vitamin A to rice to prevent blindness

1. Remove needed gene from human DNA2. Insert gene into bacterial DNA (plasmid)3. Insert hybrid plasmid into bacterium4. Bacteria undergoes transcription & translation

to produce desired protein

Genetic EngineeringStandard 5c: Students know how genetic engineering (biotechnology) is used to produce novel biomedical and agricultural products.

PHYSIOLOGY

The study of how an organism functions through its organ systems.

In with the Good, Out with the Bad9a: Students know how the complementary activity of major

body systems provides cells with oxygen and nutrients and removes toxic waste products such as carbon dioxide.

Circulatory: transport nutrients, wastes (CO2), hormones, and gases throughout body systems; maintains homeostasis

Digestive: extract & absorb nutrients from food; remove wastes; maintains water & chemical balances

Excretory: removes wastes from blood; regulates concentration of body fluids

Respiratory: move air into/out of lungs; controls CO2/O2 exchange between blood & lungs

Nervous: controls sensory & motor functions; regulates behavior & organ systems

Muscular: moves substances through body; provides movement, structure, & support

Nervous System9b: Students know how the nervous system mediates communication between different parts of the body and the body’s interactions with the environment.

controls sensory functions – when 5 senses (sight, touch, taste, smell, hearing) get stimulus from external environment, information goes up to brain through nerves and gets processed

regulates behavior & organ systems - if response is required (swatting fly), information goes back down nerves to responding organ system (muscular & skeletal)

Feedback Loops 9c: Students know how feedback loops in the nervous and endocrine systems regulate conditions in the body.

• Feedback loops can be positive (continue response that stimulus triggers) as in childbirth, breast feeding, blood clotting

• Both endocrine (hormones) and nervous (brain & nerves) systems regulate homeostasis by using feedback loops

Stimulus

Regulated Factor

Detector

Response

Brain

Skin Receptors

Sweating

• Human body wants to maintain all systems via process called homeostasis (staying same)

• If homeostasis disrupted, will employ responses to get back to original state

• Nearly all feedback loops are negative (stop response that stimulus triggers) as in hunger and thirst, and temperature changes

Hot 100°F DayBleeding

Blood Clots

Blood Vessel Receptors

Body Temp.

Feed

back

Loo

p

Normal Temp

Platelets

Electricity in the Body9d: Students know the functions of the nervous system and the role of neurons in transmitting electrochemical impulses.

• Nervous system is made of nerve cells, also called neurons

• Typical neuron contains dendrites (receive messages), cell body (location of nucleus), axon (communication cable), & axon terminals (send messages)

Chemical (dendrites)

Electrical (body & axon)

Chemical (axon terminals)

• Messages or communication is transmitted via electrochemical impulses

o Chemicals called neurotransmitters attach to dendrite receptors

o Electrical pulse sent through cell body down axon

o Chemical neurotransmitters sent out of axon terminals to other neurons at synaptic cleft (space in between two neurons)

Neurons9e: Students know the roles of sensory neurons, interneurons, and motor neurons in sensation, thought, and response.

Nervous system divided into two categories:

1. central nervous system (CNS) = brain & spinal cord

Control center of body made of interneurons (neurons that gather information from inside body) 2. peripheral nervous system (PNS) = sensory neurons & motor neurons

Sensory neurons: send info to brain from 5 senses (up)

Motor neurons: send info from brain to muscles or organs to carry out response (down)

Infection and Immunity10a: Students know the role of the skin in providing nonspecific defenses against infection.

Skin (integumentary system) is first line of nonspecific defense in protecting body against any foreign invader (pathogen) that can cause infection (usually viruses or bacteria) since it provides a barrier Break in skin barrier

allows pathogen to enter & infect Second line of nonspecific defense is phagocytosis (white blood cells that eat invader)

Infection and Immunity10b: Students know the role of antibodies in the body’s response to infection.

If phagocytes cannot prevent pathogen from infecting, body undergoes specific defense in which it identifies and targets specific pathogen Pathogen is now considered an

antigen since it causes immune response (usually a virus)

Body produces specific Y-shaped proteins called immunoglobulins (Ig) or antibodies (ANTI-body) to kill antigen (ANTIbody GENerator) using lock & key mechanism (antigen = key, antibody = lock)

Antibody is produced when helper T-cell (from Thymus) causes B-cells (from Bone) to construct specific antibody Antibodies bind to antigen, now

phagocytes can eat and destroy them

Entire process takes 7-10 days Some B cells turn into Memory

B cells that will always be prepared to immediately kill same antigen so that individual never experiences symptoms

Vaccines10c: Students know how vaccination protects an individual from infectious diseases.

A vaccine is an injection of weakened or dead antigen into the body The immune response produces antibodies as body can’t tell it’s harmless.

Antibodies with phagocytes destroy antigens Memory-B cells permanently remember antigen so if body encounters it again,

immediate attack occurs before disease symptoms develop making individual immune from disease

Bacteria & Viruses10d: Students know there are important differences between bacteria and viruses with respect to their requirements for growth and replication, the body’s primary defenses against bacterial and viral infections, and effective treatments of these infections. A microbe is anything too small

to be visible to the naked eye. Two types of microbes are bacteria and viruses.

Viruses may have a spiny outside layer, called the envelope. Viruses have a core of genetic material (DNA or RNA), but cannot reproduce on their own. They infect cells and take over their reproductive machinery to reproduce. They are not considered living.

Bacteria are single-celled prokaryotic living organisms

Bacterial infections can be treated with the non-specific immune response or antibiotics, medicines that destroy prokaryotic bacteria without harming eukaryotic humans

Viruses cannot be treated with any medicines, solely the immune response

Compromised Immunity10a: Students know why an individual with a compromised immune system (for example, a person with AIDS) may be unable to fight off and survive infections by microorganisms that are usually benign.

If the immune system is compromised or not working, individual may not be able to survive simple infections like flus or pneumonia

In AIDS (Acquired Immune Deficiency Syndrome), T-helper cells are infected by HIV (Human Immunodeficiency Virus), thus weakening immune system AIDS patient usually dies from

pneumonia