Download PASS study guide 2 - Cells_ Genetics_ Human Body

PASS Study Guide #2 – Cells/Heredity, Human Body and Ecology
Cells & Heredity
Cell
Cell Theory
Organelle Functions
Organelle Similarities &
Differences
Bacteria & Protists
Cellular Processes
Genetics
Genetic Mutations
smallest unit of life that conducts life functions; organelles (parts) cytoplasm, nucleus, cell membrane, vacuole,
chloroplasts**, mitochondria, cell wall** (**found only in plant cells); many organelles too small to be seen without
aid of microscope; cells vary in size and shape
1) All living things are made of one or more cells; 2) The cell is the basic unit of life; 3) All cells come from
preexisting cells. Know the Famous Scientist that helped developed this theory.
chloroplast – has chlorophyll & does photosynthesis; vacuole - storage center (water & waste); cytoplasm - holds other
organelles; cell membrane - controls what enters and leaves the cell (diffusion – movement of particles or water across
membrane from area of high concentration to low concentration & osmosis – diffusion of water across membrane); cell
wall – gives support and shape to cell & made mostly of cellulose; nucleus – has DNA & control center;
mitochondria/powerhouse – makes energy & does respiration; lysosomes - digesting certain materials
Similar - plant and animal have cell membrane, nucleus, mitochondria, and vacuoles
Different – plants have cell wall and chloroplasts; plant cells usually have one or more large vacuole(s), while animal
cells have smaller vacuoles, if any are present
Prokaryotic - cells that lack a nucleus and membrane-bound organelles (Bacteria & some Protists); Eukaryotic- cells
that contain a membrane bound nucleus and organelles. (Plant, animal, and protist); Unicellular organisms are
composed of one cell and would include most protists and bacteria; Multicellular – more than one cell organisms;
photosynthetic contain chloroplasts and the pigment chlorophyll (plants and some protists); Non-photosynthesizing lack chloroplasts and chlorophyll (animals)
Bacteria – Moneran Kingdom; single celled organism classified by body shapes; (spiral – corkscrew, bacillus – rod,
coccus – round)
Bacteria helpful – 1)aid in breaking down and absorbing food; 2) used to make a variety of foods including cheese and
yogurt; 3) decompose dead organisms and release those nutrients back into the environment.
Bacteria harmful – 1) can be pathogens and cause diseases like strep throat, food poisoning, and tuberculosis; 2)
Bacteria, such as wheat blight can infect plants that are used as crops.
Protists – Protista Kingdom; single celled & live in moist areas; classified by movement & way obtain food; euglena –
move by pulling w/flagella (whiplike) & have chloroplast, paramecium – move by beating cilia (hair-like oars) & uses
cilia to direct food to its mouth; amoeba – move w/pseudopods (false foot) & use pseudopods to trap food
Photosynthesis – occurs in chloroplasts; plants use sunlight to combine (CO2) & (H2O) to make (C6H12O6) & release
(O2)
Respiration – occurs in mitochondria; plants & animals breakdown (C6H12O6) & (O2) into (CO2) & (H2O) & release
energy; use to build, repair & reproduce cells
Waste elimination – get rid of harmful waste; waste moves from high concentration to low concentration
Mitosis – occurs in nucleus; cell reproduction; makes exact copy of cell; produces 2 identical daughter cells (look like
parent cell) from 1 parent cell; use for growth, replacement, & asexual reproduction
Genetic information (DNA) is passed from parent to offspring causing offspring to have similar traits as the parents;
sex cells (egg & sperm) have ½ o/DNA; Heredity/inheritance – passing of traits from one generation to next
Chromosomes – structure in nucleus that contains DNA
Genes – segment of DNA that determines inherited trait; responsible for inherited characteristics that distinguish one
individual from another; come in pairs (or two alleles); genes are expressed by genotype – set of genes carried by
organism, phenotype – physical expression o/gene; Dominant trait—always expressed (capital letters); Recessive
trait—expressed if two recessive alleles are present (lowercase letters); Homozygous – two copies of same allele
dominant or recessive; Heterozygous – one dominant & one recessive allele.
DNA has 4 nitrogenous base pairs (adenine, thymine, cytosine, and guanine) and a phosphorous and sugar backbone;
adenine always pairs with the thymine & cytosine always pairs with the guanine; RNA (ribonucleic acid) is a single
strand of nitrogenous base pairs with a phosphorous and sugar backbone. RNA is used by the cell to aid the process of
DNA transcription and translation.
Inherited Traits – characteristics passed from parent to offspring (eye color, eye shape, etc); dominant traits - always be
expressed in the phenotype. Alleles for dominant traits are represented by capital letters; recessive traits – only
expressed in the phenotype if two recessive alleles are present. Alleles for recessive traits are represented by lowercase
letters
Mutation - change in the genes of an organism. Many mutations occur randomly where others can be the result of some
environmental exposure; can be beneficial, harmful, or have neutral effect on the organism; EX. genetic disorder sickle
cell anemia is harmful to the persons that have that disorder. However, the disorder arises from a mutation to protect
humans from Malaria; most mutations are automatically repaired by enzymes and have no effect; when not repaired,
the resulting altered chromosome or gene structure is then passed to the offspring; If the mutant cell is a body cell
(somatic cell), the daughter cells can be affected by the altered DNA, but the mutation will not be passed to the
offspring of the organism (cause cancers); If the mutant cell is a gamete (sex cell), the altered DNA will be transmitted
to the embryo and may be passed to subsequent generations (cause genetic disorders).
● In some cases mutations are beneficial to organisms. Beneficial mutations are changes that may be useful to
organisms in different or changing environments. These mutations result in phenotypes that are favored by natural
selection and increase in a population
Deletion - when DNA is removed or deleted. Insertions - when DNA is inserted into another section of DNA.
Frameshift - an insertion or deletion that is not in a multiple of three. Translocation - when large chunks of DNA is
Genetic Engineering
Punnett Square
Inherited Traits Vs.
Acquired Traits
swapped between non-homologous chromosomes.
Genetic engineering is the manipulation of an organism’s genes (genome). Selective breeding - a process humans use
to breed or reinforce desired traits into a particular organism. Ex. Diversity of dogs; Genetically Modified Organisms
(GMOs) - used in food or in other commercial applications. Ex. resistance to plant diseases can be added to corn’s
genome so the plant is not affected by these diseases; Biomedical research - employs a variety of techniques to
advance medical science and improve human lives. EX. the human genome project has mapped the entire human
genome. This information can be used to inform individuals during genetic counselling and when making health
decisions.
Used determine the possibilities of the combinations of alleles that the offspring may receive; tool used to predict the
ratio or percentage of the possible genes that an offspring will have based on the genes of the parent; alleles for one
parent are placed at the top and the alleles of the other parent are placed on the left; individual squares show the
possibilities of allele pairs in the offspring; purebred genotype- two alleles are the same (TT or tt); hybrid genotype two alleles are different (Tt); monohybrid cross- cross that shows the inheritance of a single characteristic; It is
sometimes difficult to predict certain traits in humans (for example hair color or eye color) because there may be
several different genes that control these traits. You need to be able to determine the genotypic ratios and phenotypic
ratios of monohybrid crosses.
Incomplete dominance is a condition when the dominant allele does not completely mask the recessive. As a result
some of the recessive trait will be observed in the phenotype. An example of an incomplete dominance in plants may
be color of flowers. The color red is dominant over the recessive color white. Pink flowers are a result of a blending of
red and white; Co-dominance is a condition when there is more than one dominant allele. As a result, both alleles will
be expressed in the phenotype. An example of co-dominance in plants may be the color of the flowers. If both red and
white alleles are dominant, both traits will be expressed in the flower. The AB blood type in humans is another
example of co-dominance.
Inherited trait- genetically determined characteristic that distinguishes one organism from another organism ( some
dominant & some recessive & some neither); ex inherited trait in plants – color of flowers; ex. Inherited trait in
animals – eye color
Acquired trait – influenced by environmental factors (temperature, nutrients, injuries, disease, exposure to sun, living
conditions)
Human Body
Levels of Organization of
Human Body
System Major Organs
Function of Major Organs
cells, tissues, organs, organ systems, organism; cell – basic unit of structure & function in body, ex. neuron (nerve),
blood, & bone cells; tissues – group or cells working together, ex. nerve tissue – carries impulses to & from the brain,
muscle tissue – make body parts move by contracting & shortening, epithelial tissue – covers surfaces o/body,
connective tissue – connects all parts of body and provide support (tendons (muscle to bone), ligament (bone to bone),
cartilage (flexible cushion)); organ – group of two or more tissues, ex. heart; organ system (system) – group of organs
working together (CRIS DEERMIN) circulatory, respiratory, integumentary (skin), skeletal, digestive, excretory,
endocrine, reproductive, muscular, immune, & nervous
Circulatory – heart, blood vessels (arteries, capillaries, veins); Respiratory – nose, trachea, bronchi, lungs, diaphragm;
Digestive - mouth, esophagus, stomach, small intestines, large intestines, rectum, anus (2 ndary – liver, gallbladder,
pancreas); Excretory – kidneys, ureters, bladder, urethra; Nervous – brain, spinal cord, peripheral nerves; Muscular –
skeletal, smooth, cardiac muscles; Skeletal – bones; Integumentary - skin
Heart – causes blood to flow through body by its pumping action
Blood vessels – tubes that carry blood through out entire body (Artery – carries blood with oxygen & nutrients to all
parts of body, Veins – carries waste products from all parts of body back to heart, Capillaries – small vessels where
oxygen & nutrients leave the blood to go into cells & carbon dioxide & other waste products enter blood from cells)
Nose – collects air from the environment & moistens & heats the air before it enters trachea
Trachea – windpipe; moves air from nose to lungs
Bronchi – tubes that move air from trachea to lungs
Lungs - main organs where gases are exchanged between air & blood (Alveoli – in lungs where gas exchange takes
place)
Diaphragm – muscle that aids in breathing
Mouth – breaks down food into smaller pieces (Mechanical Digestion – process of chewing, Chemical Digestion –
started by saliva in mouth)
Esophagus – transport tube; carries chewed food to stomach
Stomach – continues mechanical digestion; secretes gastric juices that continue chemical digestion started in mouth
Small intestines – organ where most of the chemical digestion of food takes place; absorbs nutrients
Large intestines – organ that absorbs water from food taken into bloodstream; prepares undigested food for elimination
Rectum – short tube that stores solid waste
Anus – eliminates solid waste
Liver – organ that produces bile (Bile – breaks up fat particles)
Gallbladder – organ that stores bile
Pancreas – organ that produces digestive juices that break down food in small intestine
kidneys – get rid of urea (excess water) & other waste materials released by cells – eliminated as urine
Ureters – tubes that connect each kidney to bladder
Bladder – saclike muscular organ; stores urine until released
Urethra – tube which urine passes before removed from body
Brain – control & coordinates activities of body
Relationships of Major
Systems
Diseases
Spinal cord – bundle of nerves from brain to center of back vertebrae; connects to peripheral nerves
Peripheral nerves – branch out from spinal cord and connect to rest of body; transmit signal to & from brain
Skeletal muscles – voluntary muscle attached to bones; provide force need to move bones
Smooth muscles – involuntary muscles control many types of movement in body
Cardiac muscles – involuntary muscle that form the heart
Bones – provide shape and support for body; protects many organs and structures; produce blood cells; store minerals
(Joints – where two bones meet)
Skin- covers body; prevents loss of water; protect from infection & injury; regulates body temperature; get rid of waste
(sweat), receive information from environment; makes vitamin D
All body systems are dependent upon the circulatory system to transport materials; circulatory system works with the
excretory system to help remove wastes from the
Body; respiratory system works with the circulatory system to make sure that oxygen (O2) reaches the bloodstream
and carbon dioxide (CO2) is removed from the bloodstream; digestive system works with the circulatory system to
make sure that nutrients made available by digestion (for example glucose) get to the cells of the body; nervous system
works with the muscular and skeletal systems to direct behavior and
Movement; nervous system controls internal processes in the body (for example digestion and circulation); Muscles
control the movement of materials through some organs (for example the stomach, intestines, and the heart); muscular
and skeletal systems work together to help the body move.
Disease - condition that does not allow the body to function normally; affects organs or organ systems; either
infectious or noninfectious
Infectious disease – caused by pathogens (bacteria, virus, protist, fungus) from contaminated area, another person,
animal bite, or environment; pathogens damage single cell or attack the entire system; ex. cold, flu, athlete’s foot,
AIDS, strep throat, tetanus, pneumonia, malaria
Cold – caused by virus infecting respiratory system; multiples and attacks mucous membranes of nose & throat
causing side effects of sore throat, runny nose, & fever
Flu – caused by viral infection of respiratory system; causes fever, muscle aches, severe cough, & lasts longer than
cold
Athlete’s foot – caused by fugal infection of skin on feet; obtained from public environment; grows in warm, moist
areas between toes; can be difficult to cure
AIDS - Acquired immunodeficiency syndrome (AIDS) is caused by the human immunodeficiency virus (HIV); attacks
cells of immune system making organism unable to fight off pathogens
Strep throat – caused by bacterial infection; side effects (mild or severe) are fever, pain, redness, & swelling of throat
and tonsils
tetanus (caused by bacteria), pneumonia (caused by a virus or bacteria), or malaria (caused by a protist spread by
mosquitoes)
Noninfectious disease - caused by malfunctions in body systems that are either inherited or caused by environmental
factors; ex. diabetes, Parkinson’s disease, skin cancer, asthma, allergies, arthritis, heart disease, & multiple sclerosis
Diabetes – caused by inability to produce or use insulin properly; causes high glucose level in blood; can lead to
kidney disease, cause vision problems, or heart disease
Parkinson’s Disease – affects cells in nervous system causing them to stop affecting muscular system; symptoms are
serve shaking (tremors) & disabilities involving movement; no cure
Skin Cancer – damages outer layer skin cells; caused by damaging ultraviolet rays (UV) from the sun or tanning beds
& heredity
Asthma – affects lungs and airways that deliver air to lungs; cause periodic attacks of wheezing and difficulty
breathing when airways inflame due to dust, mold, pets, exercise, or cold weather
Ecology
Levels of Organization in
the Environment
Food Chain, Food Web,
Energy Pyramid
Changes in the
Environment
Smallest to largest – species/organism, population, community, ecosystem, biome; defined by type and
# organisms or abiotic factors present; populations compete for food, water, space, & mates;
communities interact by obtaining & use of food, space, & resources; ecosystem first level to include
abiotic factors
Habitat – place where organism lives; niche – role of organism in environment
Organisms have energy roles determined by how it obtains energy and interacts with others; roles are
producer, consumer, or decomposer; flow of energy represented by food chain, food web, and energy
pyramid
Food Chain use pictures, arrows, and words to show movement of energy through trophic levels;
trophic level – position occupied by organism (what it eats, what eats it); level 1 – producer, level 2 –
herbivore, level 3 predators, level 4 or 5 – carnivores and top carnivores
Food Web- shows interconnecting food chains uses pictures, arrows, and words; models who consumes
whom or what
Energy pyramid – show amount of energy moving through trophic levels in food chain; producer has
most energy; energy decreases as move up
Natural hazards, changes in population, and limiting factors; cause competition for food, water, space,
& shelter
Natural Hazards (landslides, wildfires, floods); landslides – falling, sliding, flowing on slope movement
Soil
Renewable and
Nonrenewable Resources
Symbiotic Relationships
of rock, earth, debris; occur when soil is moist and on slope; caused by rain, floods, earthquakes, &
humans; effects- blocks roads, destroy homes/habitats, disrupt power lines; wildfires – naturally,
accidentally, or intentionally occurring forest fire; can be beneficial to most plant growth; effects –
allow some seeds to break open to germinate (reproduce), increase air pollution, destroy
homes/habitats; floods – usually high water stage in which water overflows its natural or artificial
banks onto dry land; two types (regular & flash flood); effects – damage property, endanger
humans/animals, soil erosion, creates fertile soil
Changes in populations (birth, death, immigration, & emigration); occur when new members enter or
leave population; population density – number of organisms in given amount of space; birth rate - #
births; death rate- # deaths; immigration – organism moves in; emigration – organism moves out
The natural slowing of population growth as it nears Earth’s carrying capacity is due to an increase in
the death rate and a decrease in the birth rate as a result of: Food and water shortages, Pollution of the
environment, Spread of diseases; An increasing population can have an effect on the amount of
available clean water; If clean water is being depleted at a greater rate than it can be purified, it is not
considered renewable in our lifetime. An increasing population can have an effect on the amount of
waste that is produced. Although there are mechanisms in place to control the disposal of some waste
products, more waste is produced than can be managed effectively; Some waste products require
complicated and costly means for removal once they are introduced into the environment.
Limiting factors – affect # organisms environment can support; carrying capacity – max # organisms
that can survive in environment; climate (temperature & # rainfall in area) changes effect populations;
decrease of availability to food, water, space,& shelter (those that get them survive – those that don’t
move or die)
MVP abiotic factor because everything is directly or indirectly dependent on it; effects types of plants
that grow and animal survival; properties that can be observed (soil profile, composition, texture,
particle size); properties that can be measured (permeability, pH)
Soil profile – horizons (layers) topsoil, subsoil, & parent material; topsoil where plants grow/ animal
live & has nutrients
Composition – rock, minerals, humus (decayed organic material), air, & water; silt, sand, & clay come
from weathered rock & determine soil type; soil type effected by plants, climate, time, & slope
Texture- determined by proportions particle sizes; names are loam, sandy clay loam, silt loam, or clay
Particle size – classified from coarse to fine sand to silt to clay; gravel – particles larger that 2mm;
effects amount of water absorbed & used by plants/animals
Permeability – how freely water flows through open pores (space); closer particles are less permeable;
determined by calculating rate of drainage
pH – how basic or acidic the soil is (usually 4-10); measured by indicators; plant grows with ph 5 to 7;
lime- fertilizer alters pH allowing plants to obtain nutrients from soil
Renewable resources – replaced naturally @ rate greater or equal to rate used; (ex. Air (replaced by
photosynthesis), freshwater (replaced by water cycle), sunlight (available for billions of years), soil
(replaced by topsoil), living things (replaced by births))
Nonrenewable resources- exhaustible; use at rate faster than naturally replaced; (ex. Fossil fuels(coal,
oil, natural gas), diamonds, metals, minerals); takes millions of years to replace
Ex of depletion (soil without vegetation erodes needed topsoil, increase population demands decrease
freshwater, removing trees without replanting)
Conservation – reduce (use another resource walking vs. car), reuse (use resource again without
changing it (washing drinking glass), recycle (reprocess resource to use again as another item), protect
(prevent loss of resource)
Competition - a relationship that occurs when two or more organisms need the same resource at the
same time; can be among the members of the same or different species and usually occurs with
organisms that share the same niche; Two species with identical ecological niches cannot coexist in the
same habitat; decreases the population of a species less adapted to compete for a particular resource
Symbiosis – organisms living together with direct contact; Symbiotic relationships include parasitism,
mutualism, and commensalism.
Parasitism – one organism (the parasite) benefits at the expense of the other organism (the host). In
general, the parasite does not kill the host; Some parasites live within the host, such as tape worms,
heartworms, or bacteria. Some parasites feed on the external surface of a host, such as aphids, fleas, or
mistletoe; parasite-host populations that have survived have been those where neither has a devastating
effect on the other; Parasitism that results in the rapid death of the host is devastating to both the
parasite and the host populations; It is important that the host survive and thrive long enough for the
parasite to reproduce and spread.
Mutualism - both organisms benefit by working together; For example, bacteria, which have the ability
to digest wood, live within the digestive tracts of termites; plant roots provide food for fungi that break
Invasive Species
down nutrients the plant needs.
Commensalism - one organism benefits and the organism is not affected; EX. barnacles that attach to
whales are dispersed to different environments where they can obtain food and reproduce; burdock
seeds that attach to organisms and are carried to locations where they can germinate.
Predator- Prey Relationships
Predation- interaction between species in which one species (the predator) hunts, kills, and eats the
other (prey). This interaction helps regulate the population within an ecosystem thereby causing it to
become stable; Fluctuations in predator–prey populations are predictable. At some point the prey
population grows so numerous that they are easy to find.
Invasive species Impact: can change an entire habitat by occupying the same niche as native species;
That in turn causes unnatural competition among organisms. Environmental pressure then increases as
the carrying capacity of the ecosystem is reached; Native species that are beneficial to the environment
can be crowded out or replaced by the invasive species. EX. The zebra mussel and its effect on the
aquatic marine ecosystems of the great lakes are well documented & red fire ant of South America that
has infiltrated the southeastern US and continues to spread.
3 Ways Human can Respond to Invasive Species:
Physical Control - this would entail erecting barriers to prevent new species from entering new
environments. This can also include physical removal of new species; Chemical Control - applying
poisons (pesticides or herbicides) to eliminate new species; Biological Control - uses living organisms
to reduce or completely eliminate the invasive species. In some cases the control organism will prey on
the invasive species or in other cases the control organism causes disease in the target species.