Bio Final first semester

characteristics of living things

order, regulation, growth, energy processing, response to stimulus, reproduction, evolutionary adaptions

bacteria domain

prokaryotic, unicellular, cell wall,

Archaea domain

prokaryotic, unicellular, cell wall, extremophile

Eukarya domain

kingdoms Protista, plantae, fungi, animalia

density and dispersion patterns in populations

amount of a species in a specific area, individuals in space- important for the amount of resources, competitions

limiting factors in population size

prey vs. predators, resources available, shelter(habitat)

community’s stability relation to diversity

more diversity makes ecosystem less likely to collapse, less dependence on few species. makes it easier for ecostsyem to be adapatable and easier to self repair

how do humans affect biome

urbanization, deforestation, pollution

importance of pioneer & keystone species

Pioneer species are the first organisms to colonize/disturb an environment (like after a volcanic eruption, glacier retreat, or forest fire).

keystone species: Removing it causes significant changes to the community structure. maintain balance in the ecosystem

carbs

Monomers: Monosaccharides (simple sugars) ex. Glucose

Polymers: Polysaccharides (long chains of sugars) ex. starch

proteins

• Monomers: Amino acids (20 different kinds)

• Polymers: Polypeptides (chains of amino acids folded into functional proteins) ex.s: Enzymes, Hormones, Structural proteins

Lipids

• Monomers: Lipids are not true polymers, but their building blocks include:

  • Fatty acids and glycerol (for triglycerides)

• Polymers: Complex lipids formed by combining fatty acids and other components

organelles and their function during stress response

Nucleus- Controls gene expression by activating stress-response genes

• During Stress:
  Signals for the production of proteins that help protect the cell and repair damage.

E.R Synthesizes and folds proteins.

• Detects misfolded proteins and initiates the unfolded protein response (UPR) to restore normal function or trigger apoptosis if damage is severe.

---

3. Mitochondria

• Function:
  Produces energy (ATP) and regulates cell death.

• During Stress:
  Can release signals that trigger apoptosis (programmed cell death) if the stress is too much, or increase energy production to cope with stress.

---

4. Lysosomes

• Function:
  Break down damaged organelles and proteins.

• During Stress:
  Increase autophagy, digesting damaged components to maintain cellular health.

---

5. Golgi Apparatus

• Function:
  Modifies, sorts, and ships proteins.

• During Stress:
  Helps process stress-response proteins for transport outside or within the cell.

---

6. Cytoskeleton

• Function:
  Maintains cell shape and helps transport materials.

• During Stress:
  Reorganizes to help move damaged organelles to lysosomes for recycli

fluid-mosaic model in membrane

phospholipids heads make a mosaic, and other thing in membrane make it look like that

Diffusion

the passive movement of molecules or ions from an area of higher concentration to an area of lower concentration until equilibrium is reached. (movement of solutes)

osmosis

movement of water. the diffusion of water molecules across a selectively permeable membrane from an area of low solute concentration (more water) to an area of high solute concentration (less water).

active transport

movement of molecules against their concentration gradient — from an area of low concentration to an area of high concentration — using energy (ATP).

endocytosis

The process by which cells engulf large particles, fluids, or molecules by wrapping the cell membrane around them and bringing them into the cell inside a vesicle.

hyper/hypotonic/ isotonic

• Hypertonic: A solution with higher solute concentration than the cell, causing water to leave the cell and the cell to shrink.

• Hypotonic: A solution with lower solute concentration than the cell, causing water to enter the cell and the cell to swell.

• Isotonic: A solution with equal solute concentration to the cell, resulting in no net water movement and stable cell size.

Phagocytosis

cell eating

Pinocytosis

cell drinking

Exocytosis

the process by which cells export materials out by packaging them into vesicles that fuse with the cell membrane, releasing their contents outside the cell.

anaerobic vs. aerobic cellular respiration

• uses oxygen to fully break down glucose into carbon dioxide and water, producing a large amount of ATP.

• occurs without oxygen, partially breaking down glucose into products like lactic acid or ethanol, producing less ATP.

Two parts of anaerobic respiration

• Glycolysis: Glucose is broken down into pyruvate, producing a small amount of ATP and NADH without using oxygen.

• Fermentation: Pyruvate is converted into lactic acid (in animals) or ethanol and CO₂ (in yeast), regenerating NAD⁺ so glycolysis can continue

two parts of fermentation

Lactic Acid Fermentation: Pyruvate from glycolysis is converted into lactic acid, regenerating NAD⁺; this occurs in muscle cells during intense exercise.

Alcoholic Fermentation: Pyruvate is converted into ethanol and carbon dioxide, regenerating NAD⁺; this happens in yeast and some bacteria.

BOTH ANAEROBIC

parts of aerobic respiration

• Glycolysis: Glucose is broken down into two molecules of pyruvate in the cytoplasm, producing a small amount of ATP and NADH.

• Krebs Cycle (Citric Acid Cycle): In the mitochondria, pyruvate is further broken down, releasing CO₂ and transferring energy to NADH and FADH₂.

• Electron Transport Chain (ETC): Uses the NADH and FADH₂ to create a proton gradient that drives ATP production, with oxygen acting as the final electron acceptor to form water.

What is the evolutionary advantage of having mitochondria

they enable cells to produce much more ATP efficiently through aerobic respiration, providing greater energy to support complex cellular functions

which organisms undergo cellular respiration

All aerobic organisms undergo cellular respiration, including animals, plants, fungi, and many protists and bacteria that use oxygen to produce energ

what is mitosis

single eukaryotic cell divides to produce two identical daughter cells, each with the same number of chromosomes as the original cell. I

mitosis differ in unicellular and multi-cellular organisms

in unicellular organisms, mitosis is used for asexual reproduction

In multicellular organisms, mitosis is used for growth, tissue repair, and replacing old or damaged cells.

is the diffrence between plant and animals cells during mitosis

(cell plate) during cytokinesis and don’t use centrioles.

cleavage furrow and use centrioles to guide spindle formation.

phases of mitosis

prophase- chromosomes condense, the nuclear envelope breaks down, and spindle fibers begin to form.

metaphase- chromosomes line up along the center of the cell, attached to spindle fibers at their centromeres.

anaphase- sister chromatids are pulled apart to opposite ends of the cell by the spindle fibers

telophase- chromosomes move to opposite sides of the cell, and the cell starts to make two new nucleus

cytokinesis- the two sister cells fully split, they form their cell membrane and cell wall(for plants)

What does DNA replication have to do with mitosis and meiosis?

DNA replication is essential for both mitosis and meiosis because it ensures that each new cell gets the right amount of genetic material.

What is meiosis

production of sex cells- two divisions

What is meiosis 1

1. pairs of similar chromosomes from each parent) pair up and exchange pieces in a process called crossing over (which creates genetic variation).

2. These homologous pairs then separate and move to opposite ends of the cell.

3. The cell divides into two cells, each with half the number of chromosomes (still made of sister chromatids).

what is meiosis 2

1. The two cells from Meiosis I each divide again

2. Sister chromatids (the identical halves of each chromosome) are pulled apart to opposite ends of the cell.

3. Each cell splits, resulting in four haploid daughter cells (each has a unique set of chromosomes)

DNA Replication has to do with mitosis and meiosis

DNA replication is essential for both mitosis and meiosis because it ensures that each new cell gets the right amount of genetic material.