IB BIO Unit 3

Cell

the basic structural, functional, and biological unit of all living organisms

Cell Theory

1. all living things are composed of cells

2. cells are the basic unit of structure and function

3. cells came from pre-existing cells

Microscope

an instrument used to produce an enlarged image of a small object (magnification) while allowing distinct, close points to be seen as separate (resolution)

Scale Bar

is defined as a short, straight line drawn next to a biological diagram, sketch, or micrograph that represents the actual, real-world size of the specimen before it was magnified

Resolution

the ability of a microscope or the human eye to distinguish two close objects as separate entities rather than a single, blurred image.

Electron Microscope

greater magnification and resolution allows us to see better details so that small structure such as ribosomes

DNA

the genetic material

Cytoplasm

composed of many things mostly water, where most metabolism occurs

Plasma Membrane

controls what enters and exits composed of phospholipids

Nucleoid Region

contains a single circular chromosome, it contains DNA which holds genetic material of the growth and development of the cell

Prokaryote

cell wall, cytoplasm, plasma membrane, 70s ribosomes, nucleoid Region, flagellum, pillus

Eukaryote

plasma membrane, cytoplasm, 80s ribosomes,nucleus, chromosomes,mitochondrion, vacuoles, lysosome, rough er, smooth er, golgi apparatus, cytoskeleton

Metabolism

complex network of interdependent and interacting chemical reactions

Ribosome

responsible for protein synthesis

Nucleus

chromosomes associated with histone proteins located here,has a double membrane with pores allowing mRNA to enter the cytoplasm

Chromosome

composed of DNA wrapped around histone proteins, DNA is the genetic material with information for the growth + development

Sister Chromatids

located in nucleus with DNA wrapped around histone proteins and contains genetic information (two of them)

Histone Protein

a family of basic, positively charged proteins found in the nucleus of eukaryotic cells that associate with DNA to form structural units called nucleosomes.

Organelle

is a specialized subunit within a cell that has a specific job to perform, much like an organ does in the body

Mitochondrion

aerobic respiration producing ATP, 70s ribosomes

Rough endoplasmic reticulum

membrane bound structure with ribosomes attached, site of protein synthesis, involved in transporting protein to golgi

Smooth endoplasmic Reticulum

membrane structure with structure with no ribosomes,involved in lipid synthesis and detoxification

Golgi Apparatus

modifies and packages proteins to be exported

Vacuole

plants have large ones to store nutrients, animals have small ones which are involved with removal of waste

Lysosome

specialized vesicles, containing enzymes involved in digestion of large molecule

Cytoskeleton

composed of protein microtubes and is involved in maintaining cell shape, moving organelles and nuclear division

Unicellular

an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells.

Nutrition

organisms obtain and use nutrients (growth + development)

Movement

changing position of an organism

Growth

increase in mass or size

Response to Stimuli

ability of organisms to respond to internal or external factors

Reproduction

production of offspring

Plastids

a specialized, double-membrane-bound organelle found in plant and algal cells that is involved in photosynthesis, pigment synthesis, and food or nutrient storage.

found in: chromoplasts, chloroplasts, amyloplasts

Chloroplasts

a double-membrane-bound organelle in plant and algae cells that serves as the site of photosynthesis, converting light energy into chemical energy

Centrioles

paired, cylindrical organelles composed of microtubules that organize the spindle fibers during cell division in animal cells

Fungal Hyphae

have filamentous structure called hyphae, which may be separated by internal cell walls called septa. 

Aseptae

(or coenocytic) fungal hyphae are continuous, long, thread-like structures that lack internal cross-walls (septa), resulting in a single continuous cytoplasm containing multiple nuclei

Cell Wall

is a rigid, non-living, extracellular layer that surrounds the plasma membrane of plant, fungal, and prokaryotic cells, providing structural support, shape, and protection against mechanical stress and turgor pressure

Microvili

microscopic, finger-like cellular protrusions that increase the surface area of the plasma membrane for absorption

Sap Vacuole

large, permanent, membrane-bound organelle found in the cytoplasm of plant cells that contains cell sap.

Flagellum

a long, whip-like, protein-based structure projecting from the cell surface that rotates or flexes to provide cell motility (movement).

Cilia

short, hair-like membrane protrusions on eukaryotic cells that coordinate a back-and-forth beating motion to move fluid across the cell surface or propel the cell

Cellulose

a structural polysaccharide composed of long, unbranched chains of β-glucose monomers linked by β-1,4-glycosidic bonds.

Peptidoglycan

a large polymer consisting of glycan (sugar) chains cross-linked by short peptide (amino acid) chains that forms the structural backbone of the bacterial cell wall.

Pilus

a hair-like sub-microscopic structure found on the surface of many bacteria.

Gametes

reproductive cells (such as sperm and egg/ova) that contain a single set of chromosomes and fuse during fertilization to form a diploid zygote

Fertilization

the fusion of the nuclei of two haploid gametes (a sperm and an egg) to form a single diploid zygote.

Zygote

initial diploid single cell formed when two haploid gametes (a sperm cell and an egg cell) fuse during fertilization.

totipotent

Stem Cell

an unspecialized cell that has two key properties:

1. Self-Renewal: They can continuously divide and replicate through mitosis.

2. Potency: They have the capacity to differentiate (develop along different pathways) into specialized cell types.

Totipotent

can differentiate into all cell types, including embryonic and extra embryonic tissues such as the placenta. has the potential to form an entire organism

Pluripotent

almost any type of body cell, but can independently form an entire organism because they can’t produce all extraembryotic tissue

Multipotent

specialized for particular function, only produce cells of their own type, if they are capable of dividing at all

Embryonic Stem Cells

unspecialized cells derived from the inner cell mass of a blastocyst that feature unlimited self-renewal and pluripotency. [1, 2, 3]

Adult Stem Cells

multipotent somatic (body) cells found in specific adult tissues—such as bone marrow, skin, and liver—that can divide and differentiate into a limited range of closely related cell types specific to that tissue.

Specialized Cells

cells that have developed distinct structures and functions to perform a specific role through a process called differentiation

Cell Differentiation

is the developmental process where newly formed, unspecialized cells (like stem cells) become structurally and functionally distinct as they mature

Morphogens

a signaling molecule or chemical (often a transcription factor or protein) that diffuses across a developing embryo or tissue, forming a concentration gradient that determines the fate of cells based on their position

Stem Cell Niche

location in an adult body where stem cells can be mainained or promoted to proliferate and differentiate

Neurons

specialized cells in the nervous system that function to transmit electrical impulses (nerve signals)

4-100 um and can have a length of over 1m

Striated Muscle Cells

are atypical multinucleate cells forming from the fusion of several cells. can range in length from a few millimeters to several centimeters, and have a diameter of 10 to a 100µm.

Scientific Model

is a conceptual, mathematical, or physical representation used to explain, visualize, or predict biological phenomena that are difficult to observe directly.

Erythrocytes

(red blood cells) specialized, biconcave cells without a nucleus whose primary function is to transport oxygen around the body. diameter of 6 to 8 um allowing them to move through capillaries

Proximal Convulated Tubule

the first coiled section of the nephron after Bowman's capsule responsible for selective reabsorption of useful substances from the glomerular filtrate back into the blood

Nephron

the functional and structural unit of the kidney responsible for filtering blood, removing metabolic wastes, and regulating water and salt balance

Multicellular

an organism composed of more than one cell that work together, where cells differentiate through selective gene expression to perform specialized functions.

Tissues

a group of cells working together

Organs

a group of tissues working together

Organ Systems

a group of organs working together

Emergent Properties

arise from the interaction of componet parts, the whole is greater, than the sum of the parts

-cheetahs: effective predators due to the intergration of their body systems

Nervous System

is the network of nerves that send electrical messages around the body

Endocrine System

a network of glands that secrete chemical messengers into the bloodstream for transport to the target tissues and organs

Blood Plasma

Transport systems transport a wide range of substances between cells and tissues.

• Oxygen from the lungs to respiring tissue, using red blood cells

• Carbon dioxide from respiring tissues to the lungs

• Hormones from endocrine glands to target cells

• Nutrients from the digestive system to the liver for storage, or to other organs for assimilation

• Antibodies produced by white blood cells are transported to sites of infection

• Urea from the liver to the kidneys for excretion

Effector

an organ, tissue, muscle, or gland that produces a physiological response to a stimulus after receiving a signal from the central nervous system (CNS).

Circadian Rhythms

physcial mental and behavioral changes that follow a 24 hour cycle, respond to light and dark and affect most living things

Melatonin

secreated by the pineal gland, helps establish a cycle of waking during daylight and sleeping during the darkness

Pineal Gland

the hypothalamus and this work together to regulate the endocrine system, this stimulates other glands in the body to release specific hormones

Epinephrine/Adrenaline

secreted by the adrenal glands to prepare the body for intense physical activity and facilitates intense muscle contraction (widening of the bronchides, liver converts glycogen into glucose, heart pumps faster and harder, blood flow is redirected, pupils dialate)

Adrenal Glands

are a pair of small, triangle-shaped endocrine glands located on top of each kidney, consisting of an outer cortex that produces steroid hormones and an inner medulla that secretes catecholamines for the fight-or-flight response

Baroreceptors

located in aorta and carotid arteries, they stretch sensitive monitor blood pressure

they send signals to medulla oblongata

Chemoreceptors

located in the aorta and carotid arteries, the function is to detect changes to blood chemistry including CO2 and O2, sends signals to the medulla oblongata

Digestive Systems

an organ system composed of the alimentary canal (where food passes directly through) and accessory organs (which secrete fluids or assist without food entering them) that work together to break down large, insoluble food molecules into small, soluble monomers through mechanical and chemical digestion, and absorb those nutrients into the bloodstream.

Peristalsis

the voluntary relaxation and contraction of muscles which move contents along the digestive system

Autonomic Nervous System

responsible for the control of bodily functions which are not under conscious control, such as breathing, control of heartbeat, and digestion

Enteric Nervous System

a branch of the autonomic nervous system which controls the movement of food along the digestive system

Swallowing

The tongue pushes the chewed food ball (bolus) to the back of the mouth.

Involuntary Control: Once the bolus enters the pharynx, the autonomic nervous system takes over. The epiglottis covers the trachea to protect the airway, and peristalsis (waves of smooth muscle contraction) forces the food down the esophagus toward the stomach

Egestion

the removal of undigested and unabsorbed food material from the digestive tract as feces (via the anus or mouth)

Voluntary Control

swallowing of food and egestion of feces is an example of this of the central nervous system

Involuntary Control

movement of food from the oesophagus to the rectum by peristalis is an example of this of the enteric nervous system

Homeostasis

maintaining a stable internal environment within the body, within preset limits despite fluctuations in the external environment

body temp: 36c-37.5c

blood pH: 7.35-7.45

Blood glucose: 3.9 mmol/L to 5.6 mmol/L

blood osmotic: 275 mOsm/kg to 295 mOsm/kg is the solutes in the blood of water

Negative Feedback

response that reverses a detected change to return the body to homeostatic equilibrium

always come in two loops that counter balence

Positive Feedback

response that amplifies a detected change, further increase or decrease the variable, the variable would not return to a set point

nobody wants to be in this state

Hormones

chemical messengers released by endocrine glands

travel through blood system

Alpha Cells of Islets of Langerhans

endocrine cells located within the islets of Langerhans in the pancreas that synthesize and secrete the peptide hormone glucagon to increase blood glucose levels

Beta Cells of Islets of Langerhans

specialized endocrine cells in the pancreatic Islets of Langerhans that synthesize and secrete the hormone insulin to lower blood glucose levels

Insulin

is a hormone that is released when blood sugar is to high, it travels through the blood cells to target cells (liver+muscles) then binds to receptors on target cells triggering glucose uptake into glycogen for storage

muscle cells use more glucose for aerobic respiration, lowering blood glucose levels back to normal

Glucagon

is a hormone that is released when blood sugar is to low, it travels through the blood stream to the liver cells, binds to these receptors on the liver cells membrane, the hormone trigger the breakdown of glycogen into glucose, glucose released into the blood stream restoring normal levels

Glycogen

polysaccharide (a branched polymer of α-glucose) that acts as the primary short-term energy storage molecule in animals and fungi, can be converted into this for storage or converted into glucose to increase blood sugar

Diabetes

a chronic metabolic disorder characterized by persistently high blood glucose levels (hyperglycemia) caused by the body's inability to produce or effectively respond to insulin

Type 1 Diabetes

An autoimmune disease, where the beta cells are damaged. The body no longer produces insulin.

mainly genetic

cannot be prevented

Blood sugar monitoring and injections of insulin.

People with this diabetes benefit from a healthy diet and regular exercise.