Biology Midterm semester 1

Prokaryotic cell

a cell that does not have a nucleus or membrane-bound organelles

* the only prokaryotes are bacteria
* Prokaryotic cells do have DNA ; DNA is not just in nucleus

Eukaryotic cell

a cell that contains a nucleus and membrane-bound organelles

* All organisms except bacteria are eukaryotes

plasma/cell membrane

the boundary between the cell and its environment

Selectively permeable

allows some molecules into the cell while keeping others out

phospholipids

The phospholipids form a bilayer, layer is arranged so tails point toward each other

proteins

some protists help self-identify each other. These proteins act as name tags

transport protiens

serves as a passageway into and out of a cell

* molecules unable to get through the phospholipid bilayer can sometimes enter through transport proteins

Cholesterol

Helps stabilize the plasma membrane by preventing the tails of the phospholipids from sticking together

carbohydrate chains

work together with certain proteins to help cells identify each other

Cytoplasm

the clear, gelatinous fluid between the nucleus and the cell membrane

nucleus

the central membrane-bound organelle that manages cellular function and contains DNA

chromatin

DNA that is not tightly coiled; cell is not dividing

Chromosome

DNA is tightly coiled; cell is dividing

nucleolus

spherical organelle found inside the nucleus where ribosomes are made

Nuclear envelope

the membrane that surrounds the nucleus

nuclear pores

holes in a nuclear envelope through which substances can pass

ribosomes

* both prokaryotic and eukaryotic
* attatch to the rough ER or float freely
* NOT SURROUNDED by a membrane

Vacuole

sac like organelle that stores water food and waste

plants contain 1 large and animals have multiple smaller ones

provide plant w support

Lysosomes

Sac like organelle that contains digestive enzymes (Intracellular)

* can digest excess or worn out organelles and allow parts to be recycled

Chloroplasts

organelle that captures energy from sunlight and converts it into chemical energy in food

Mitochondria

Organelle that transforms the energy stored in food molecules to ATP, common in muscle cells

* provide energy the cell needs
* inner membrane is highly folded called cristae. Folding allows large surface area to fit

Allele

segment of DNA on a chromosome

Dominate alleles

an allele that masks another allele

recessive allele

an allele that can be masked by another allele

homozygous

Same

Dominate- DD

ressessive-dd

Heterozygous

different

Dd

Genotype

Genetic makeup of an organism

USE ALLELS TO REPRESENT

Phenotype

Physical make up of an organism

ex: Black, white, red

producers

autotrophs

make their own food

example- grass

Primary consumers

heterotrophs

herbivores

example- squirrel

secondary consumers

carnivores or omnivores

* snake

Tertiary consumer

carnivores or omnivores

* lion

10% rule of energy transfer

Only 10% of energy available at one level is passed on to the next

competition

the struggle among organisms for limited natural resources

Competitive exclusion principal

two species cannot occupy the same niche at the same time and place

predation

when one organism feeds on another

predator adaptions

1. Fangs
2. teeth
3. stingers
4. camouflage

predator adaptations

Plants- produce toxins

Active- fight or flight

passive- hiding/ camoflauge

Batesian mimicry

harmless but looks dangerous

Mullarian Mimicry

dangerous forms that look like eachother

Are virus’s living or nonliving

Missing key characteristics of living organisms

capsid

protein sheath that surrounds the nucleic acid in a virus

nucleic acid

genetic material

envelope

membrane- like layer that covers the capsid in some virus’s

* gives virus spherical shape

glycoprotiens

proteins with attached carbohydrate molecules

* Help virus gain entry into the cell

Lytic Cycle

The cycle of viral infection and cell destruction

Lysogenic cycle

Virus becomes part of the host cell and hides

Viroid

an infectious, single strand of RNA

Domain Archea

Commonly found in extreme enviroments such as salt lakes and hot springs

* eukariotic cells

Domain Bacteria

**Prokaryotes** are members of domain bacteria and are found everywhere

ex ecoli and c botulinum

Bacillus

rod

coccus

sphere

spirillum

spiral

Thermoacidophiles

ocean vents

Methanogen

wet lands and digestive systems

Halophiles

salt/ salt lakes

Conjugation

occurs when two bacteria exchange genetic material by transferring plasmids

* can form antibiotic resistance

Gram +

Stain purple

Thick cell wall

Does not have extra cell membrane

Gram -

Stain Pink

Thin Cell wall

No extra cell membrane

Difficult to treat because cell membrane is to thin that they cannot trap the antibiotics

endospore

some bacteria survive harsh conditions by forming thick walled structures

can survive: Boiling, radiation, acid

ex. anthrax

pathogen steps

1. Must find pathogen in animal w disease
2. Must isolate pathogen from sick animal in lab
3. Must inject pathogen in healthy animal
4. pathogen taken from 2nd animal must show same

Antibiotics

chemicals that inhibit the growth or kill microorgnaims

some cna become resistant

ex. TB and staph

Emerging diseases

newly recognized

* Zika
* covid 19 NOT CORONA VIRUS

cilliates

\n unicellular \n cillia \n heterotroph \n animal-like \n hair-like \n reproduce through conjugation

Amoeboids

Unicellular \n Pseudopodia \n heterotroph \n animal like \n engulf food

Flagelletes

unicellular \n move by flagella \n heterotroph \n animal

Euglenioids

Unicellular \n move w flagella \n both auto troph and heterotroph \n plant like

Diatoms

unicellular \n DO NOT MOVE \n autotroph \n plant \n Great in cleaning agents and tooth paste

Slime molds

unicellular \n Move w cytoplasm \n heterotroph \n fungi \n form spores and absorb from soil \n decomposers

sexual reproduction in unicellular

1 haploid cell divides by binary fisson

2 gametes fuse to form a diploid zygote and zygospore

haploid cells break out of zygospore and grow into mature cells

Sexual reproduction multicellular

sporeophytes to spores to gametophytes to gametes to zygote

Giardiasis

Flagellete

caused by intestinal parasite

causes diarrhea

contaminated water

Chagas disease

Flagellete \n kissing bug \n chronic stage can result heart disease

Malaria

Sporozoan \n Spread by mosquito

kills 3 million each yr

cryptosporidiosis

sporozoan \n causes severe diarreah

contaminated water

oxygen production in protists

* plantlike protists along w cyanobacteria produce at least 1/2 of earth's oxygen and consume carbon dioxide


* many protists are important decomposers contribute to recycling of carbon and nitrogen

Agar

produced by algae

diatamasous earth

made by diatoms, fertilizer

Algal blooms

rapid increase in the population of algae in an aquatic ecosystem

symbiosis

protists supply coral w nutrients, coral provide a stable environment, nitrogen and minerals

Animal Like protists

amoeboids \n ciliates \n Flagellates \n sporozoans

saprobe

feed on dead organisms

example- Cytrid

parasite

Fungi that absorb nutrients from living hosts

How do Fungi gain their nutrients

* get nutrients through enzymes
* digest outside of their bodies
* suck the nutrients back up and absorb it across cell walls

Hypahe

Thread like strands throughout the fungus body

chitin

tough carbohydrate that is also found in covering of insects

ascus

sac like reproductive structure that produces spores

basidia

club shaped cells under the basidiocarp

Ascomycetes

* name for sac-like ascus that produces spores
* ascocarp forms when 2 hyphae from different mating types meet (Sexual reproduction)
* Each ascus produces 8 spores
* conidiophores in the group form conidia during asexual reproduction
* Have dikaryotic cells that form ascocarp
* ASEXUAL is more common than sexual

Club Fungi Aka BAsidiomycetes

* Asexual reproduction is rare
* basidiocarp forms when 2 hyphae from different mating tupes meet
* name for cells called basidia that produce spores
* Puffballs
* shiitake mushrooms
* bracket fungi
* fairy rings
* toxic mushrooms (death cap)

zygote fungi

* name for sexual reproductive structures that produce zygotes in tough capsule
* reproduction occur when hyphae from two mating types come together
* not male or female, + and -
* example- bread mold

ASEXUAL REPRODUCTION IS MOST COMMON

economic importance of fungi

Used for foods, medicines, research alternative foods and pest control

yeast

fungi that exists in primarlily unicellular state

* used in baking, brewing etc

Lichen

an association between a fungus and a photosynthetic partner, such as a cyanobacteria

Mycorrhizae

the hyphae transfer phosphorus and other minerals from the soil to roots

plants supplies carbohydrates to the fungus

symptoms of fungal toxins

Diarreah, vomiting, liver damage and death

Alfatoxins

a type of fungus that contaminates corn, peanuts, and cottonseed produces alfatoxins that causes liver cancer

ergot

fungus that infects grain- led to Salem witch trials

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**Fungus that causes severe reactions when ingested, such as hallucinations, muscle spasms, and confusion**

Septa

partial cell walls

caps

allow cytoplasm and nutrients through