IB Biology --> Topic 1 (Introduction to cells)

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

the Phosphid Bilayer must be ______ to the particle to let it through

permeable

facilitated diffusion

Movement of specific molecules across cell membranes through protein channels (phosphide bilayer must be studded to allow it to happen)

Osmosis

diffusion of water across a selectively permeable membrane

what ways does water move

hypotonic to hypertonic

hypotonic solution

Solute concentration is less than that inside the cell; cell gains water

hypertonic solution

Solute concentration is greater than that inside the cell; the cell loses water

isotonic solution

a solution whose solute concentration is equal to the solute concentration inside a cell

active transport

the movement of materials through a cell membrane using energy (ATP)

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

protein pumps

transport proteins that require energy to do work

Endocytosis

A process in which a cell takes in materials (like proteins) from the outside by engulfing

Exocytosis

Process by which a cell releases large amounts of material

Mitosis

process in which one cell makes 2 identical daughter cells

Chromatin

a combination of DNA and protein molecules that make up the chromosomes

sister chromatids

one of two identical halves of a replicated chromosome

Centromere

Area where the chromatids of a chromosome are attached

Interphase

longest phase of the cell cycle

3 phases of interphase

G1, S, G2

G1 phase

cell growth, organelle duplication, protein synthesis

S phase

DNA replication

G2 Phase

The second growth phase, of the cell cycle, Cells prepare to divide

Phases of Mitosis

prophase, metaphase, anaphase, telophase

Prophase

Chromosomes become visable, nuclear envelop dissolves, spindle forms

Metaphase

Chromosomes line up in the middle of the cell

Anaphase

Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell

Telophase

the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed.

Cytokinesis

division of the cytoplasm, cell plate or cleavage furrow

Mitotic index

number of cells in mitosis/total number of cells

Cancer

caused by an uncontrolled division of cells

4 types of cancer

carcinomas, sarcomas, lymphomatic, leukemias

carcinomas

cancers that arise in the skin, body chamber linings, or glands

sarcoma

connective tissue cancer

lympatic

affects the lypatic tissue and spreads through the body

Leukemia

cancer of the blood or bone marrow characterized by the abnormal increase in white blood cells

radiotherapy

treatment using radiation

tumor

a swelling of a part of the body

malignant

cancerous cells invading normal tissue

benign

cell growth that doesnt create long term effects

metastasis

The spread of cancer cells beyond their original site

Carcinogen

A cancer-causing substance

Mutation

A change in a gene or chromosome.

Oncogenes

genes that can transfer into a tumor

tumor suppressor

gene that protects from cancer

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

cell membrane

A cell structure that controls which substances can enter or leave the cell.

Pili

Appendages that allow bacteria to attach to each other and to transfer DNA

Golgi apparatus (GA)

A system of membranes that modifies and packages proteins for export by the cell

Receptor

protein that receive and send signals

Prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

Hydrophobic

Water fearing

Nucleolus

Found inside the nucleus and produces ribosomes

Lysosomes

An organelle containing digestive enzymes

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Capsule

provides the cell with moisture

Vesicles

small membrane sacs that specialize in moving products into, out of, and within a cell

Enzyme

(ATP) A type of protein that speeds up a chemical reaction in a living thing

Eukaryote

A cell that contains a nucleus and membrane bound organelles

Hydrophilic

water loving

Amphipathic

having both a hydrophilic region and a hydrophobic region

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Ribosomes

Makes proteins

Flagella

whiplike tails found in one-celled organisms to aid in movement

Chloroplast

An organelle found in plant and algae cells where photosynthesis occurs

Adhesion

anchors the cell membrane to the cytoskeleton

Cristae

folds in the inner membrane of mitochondria

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

Cilia

The hairlike projections on the outside of cells that move in a wavelike manner

Cytoskeleton

A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

recognition

proteins that identify whether the substance is foreign or not

Nucleoid

A non-membrane-bounded region in a prokaryotic cell where the DNA is concentrated.

is a eukaryotic ribosome 70s or 80s

80s

is a Prokaryotic ribosome 70s or 80s

70s

fluid mosaic

another name for phospholipid bilayer

Cell wall

A rigid layer of nonliving material that surrounds the cells of plants and some other organisms.

Saturated

Containing the highest amount of substance

Unsaturated

contains less than the maximum amount.

Binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Periferal

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

Insulin

A hormone produced by the pancreas or taken as a medication by many diabetics

Peptidoglycan

In bacterias cell walls

Integral

proteins embedded in the plasma membrane covers 100%F

Endroplasmic Reticulum (ER)

A system of folded sacs and pathways.

7 characteristics of life

responsiveness to the environment, growth and change, metabolism, homeostasis, reproduction, exchanging energy and matter, population changing over time

organization of life

cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere

spontaneous generation

Hypothesis stating that life could arise from nonliving matter. aristotle

Francisco Redi

used meat experiment with maggots to begin showing spontaneous generation wasn't true.

cell theory

idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells

surface area to volume ratio

6a^2/a^3