Biology - First Semester - Freshman Year

pool studying time - 2 hours 30 mins

15 mins - COL

15 mins - photoynthesis

15 mins - macromolecules

15 mins - biogeochemical cycles

15 mins - ecology

15 mins - parts of a cell

15 mins - conservation of matter

15 mins - homeostasis

15 mins - negative and positive feedback

15 mins - cellular respiration

Characteristics of life:

the different characteristics of life are the requirements an organism needs to meet in order to be considered living.

  1. made up of cells

cells are the smallest thing that can be considered alive

they all have a cell membrane, DNA, ribosomes, and cytoplasm.

unicellular organisms: bacteria, paramecium, amoeba

multicellular organisms: plants, animals (the adult human body is made up of 50 to 100 trillion cells)

  1. reproduce

sexual reproduction: two cells from different parents combine to make the first new cell of the new organism

asexual reproduction: one parent can make a new organism by splitting off a portain of itself

sexual repoduction examples: maple trees, birds, humans

asexual reproduction: bacteria, hydra.

  1. based on a genetic code

all cells have DNA

DNA contains the directions for inheritance

dogs produce dogs, bacteria produces bacteria, and offspring inherit all of their traits from their parent(s)

  1. Grow and develop

growth: all organisms will increase in size

development: the cells in many organisms differentiate (become different). This allows the organism to become more complex

growth - a kitten growing into a cat, a sprout becoming a large oak-tree

development - a caterpillar becomes a moth, humans start out as one cell and later have 85 different types of cells

an organism has to grow and develop to be considered living.

  1. Obtain and use materials and energy

organisms must take in energy from their environment

plants get energy from sunlight, insects and animals eat plants and other animals to get energy, fungi get energy from dead organisms

  1. respond to the environment

since the environment is always changing (the temperature, amount of light and water, etc. vary), organisms must be able to adjust.

a plant seed will only grow if there is enough water, and its leaves and stems grow towards the light.

  1. maintain a stable internal environment

homeostasis: how organisms keep their internal conditions stable.

in order to maintain a stable interal environment, humans sweat when it gets hot, and shiver when it gets cold.

shivering is caused by the atoms moving more closing together because of the cold temperatures

  1. evolve

the characteristics of a group may change over time.

traits that make an individual more likely to survive and reproduces are more likely to be passed on to the next generation.

humans often use antibacterial soap when they wash their hands. the soap kills most of the bacteria, but some of the bacteria just happen to be resistant to the soap and survive. Now, only soap resistant bacteria are left living on those hands. these bacteria reproduce and the new population of bacteria that are resistant to anti-bacterial soap!

Photosynthesis:

the formula for photosynthesis is 6CO2 + 6H2O + energy + 6O2 + C6H12O6

autotrophs are organisms like plants that produce their own food through photosynthesis

most plants appear green because chlorophyll reflects green light

the statement that describes the overall process of photosynthesis is plants convert light energy into chemical energy

plants take in the sunlight and other reactants (H2O, cardon dioxide), and turn them into glucose and oxygen

the main product of photosynthesis that provides energy to the plant is sugar (glucose)

plants primarily obtain the water needed for photosynthesis from the soil, obsorbed by the roots

the essential gas that is released into the atmosphere as a byproduct of photosynthesis is oxygen

the pigment in plant cells that’s responsible for capturing sunlight for photosynthesis is chlorophyll

photosynthesis plays a crucial role in the carbon cycle by removing carbon dioxide from the atmosphere

because of photosynthesis, the world is able to keep sustaining life on Earth

By removing carbon dioxide from the atmosphere, photosynthesis helped to mitigate climate change and global warming.

stomata is the tiny pores on the surface of leaves that allow fr the exchange of carbon dioxide and oxygen.

during photosynthesis, carbon dioxide molecules are used to build glucose.

photosynthesis happens in the chloroplasts of the plant cell

CO2, H2O, and O2 all pass through the stomata

Phloem is the vascular tissue in plants that conducts sugar and other metabolic products downward from the leaves

Xylem is the vascular tissue in plants responsible for transporting water and dissolved minerals from the roots upward to the stems and leaves, providing structual support, and storing some substances.

Macromolecules:

carbohydrates - main source of energy, monomer is monosaccharide, polymer is polysaccharides, contains CHO (1:2:1), and examples are glucose, fructose, cellulose, starch

lipids - makes up cell membrane, monomer is fatty acid, polymer is triglyceride, contains CHO (2:1), and examples are corn, oil, and lard

proteins - helps to control the rate of chemical reactions, monomer is amino acid, polymer is protein, contains CHON, and examples are enzymes and hormones

nucleic acids - contains genetic code, monomer is nucleotide, polymer is nucleic acid, contains CHONP, and examples are DNA and RNA

enzymes are proteins that help speed up chemical reactions in our bodies. Any chemical that speeds up reactions is called a catalyst. Enzymes work with many different processes, one being digestion. substrates are binded by enzymes to speed up these processes.

Biogeochemical cycles:

Heterotrophs get two things from their food, energy and nutrients.

nutrients = matter

through an ecosystem, energy flows in one direction

for energy, what doesn’t get passed on is released, and doesn’t come back

nutrients moves in a cycle, moving in and out of the chain.

for nutrients, what does not pass on is released, and does come back.

the nutrients get passed to the organisms at the next trophic level when they are eaten.

when an organism dies, it goes back into the soil to bring the nutrients to the producers.

Ecology:

The types of animals that can eat both plants and animals are called omnivores

Organisms that eat dead and decaying organisms are called detritivores

The first trophic level of every food chain is always made of producers

The original source of almost all of the energy used by living things is sunlight.

competition is when organisms compete for limited resources.

competition can occur within same or different species

some resources that animals can compete for can include land, water, shelter, mates, etc.

competition is a negative negative situation because it puts both sides at risk of extinction

predation is when one organism hunts and consumes another organism

predation is essential for keeping the population of a species at bay.

predation is a positive negative relationship because the hunter benefits from getting food and resources from the prey, while the prey dies.
commensalism is when one organism benefits, while th other is unaffected.

parasitism is when one organism benefits, the other is harmed.

parasites live on/inside the host

parasitism is a positive negative relationship because the parasite benefits, but the host is harmed.

mutualism is when both organisms benefit from the interaction

for mutualism, it increases both organisms survival chances.

mutualism is a positive positive relationship, because both organisms benefit.

Parts of a cell:

the cell wall is the strong outside boundary of a plant cell

the nucleus is the control center of the cell

the mitochondria supplies energy to the cell

the ribosomes make proteins for the cell

the chloroplast is how plants can do photosynthesis

the cell membrane allows materials into and out of the cell

Law of conservation of matter:

Matter cannot be created nor destroyed

during a chemical reaction, the molecules break apart and rearrange to form new molecules

a very important chemical reaction is photosynthesis

digestive system quiz notes:

  • the major function of the digestive system is to break food down into nutrients so that they can be absorbed and used by cells

  • the correct passage of food through the digestive system is mouth, esophogus, stomach, small intestine, large intestine.

  • the gallbladder, pancreas, and salivary glands are alll accessory organs that are still important for the digestive system even thought food never enters them.

  • mechanical digestion breaks large pieces of food into smaller foods.

  • the small inestine is so much longer than the rest of the oragsn so thr small intestine can chemically digest all of the macromolecules and absorb all of the nutrients from those macromolecules.

  • chemical digestion is the proccess in the digestive system that takes the most time.

  • the large intestine absorbs water and forms solid waste

  • the pancreas produces enzymes and insulin.

semester 1 study guide notes:

  • living things often need to comepete for resources because most resources are limited and only a certain number can be given to each group

  • some things living things need to compete for are food, water, or mates even.

  • mutualism - the monarchs drink nectar from and lay their eggs on the milkweed. the hatched larvae eat the milkweed leaves and acquire their poisonous chemicals. Predators are less likely to eat monarch larvae and adults. milkweed gets pollinated by the adult monarch.

  • commensalism - skunks and oppums live in burrows dug by woodchucks. they gain a home, and the woodchucks arent helped or harmed.

  • competition - lions must protect their food from hyenas who try to take the food away from the lions'

  • parasitism - a tick feeds on a dogs blood and harms the dog.

  • two benefits of livung in a group are: if an animal is struggling (sickness, starvation), there are others to help, and they gain more resources because every one of them is hunting and finding resources.

  • two negstived of living in a group are:

  • when there is more predators, there are less prey. but when there are less predators, theres more prey.

  • the population that increases first is the prey, because without a lot of prey, the predator population wont ever increase and in fact itll die out.

  • limiting factors affect the size of a population by restricting a population from surviving, given that if once of these factors is applied the population as a whole wont have access to the resource, which could cause the population to die out. Then again, these factors help the population not overgrow.

  • if there were no limiting factors, the populations would get overpopulated, and there would be way too many species.