Year 10 Biology, cells and stuff

MRS GREEN

movement, respiration, sensitivity, growth, reproduction, equilibrium (homeostasis), excretion, nutrition

Unicellular

Made of a single cell

multicellular

Consisting of many cells

5 kingdoms

Monera, Protista, Fungi, Plantae, Animalia, (MAPPF)

Monera

bacteria, a biological kingdom made of prokaryote, single cell, no nucleus

Protista

a kingdom of mostly one-celled eukaryotic organisms that are different from plants, animals, bacteria, and fungi. large group of cells like cholera

Anamalia

animals, basic groups of living things that comprises all animals, multicellular organisms

Plantae

plants, all organisms that have chlorophyll

Autotrophic

make their own food, like trees

Heterotrophic

Organisms that obtain their nutrients or food from consuming other organisms.

Eukaryote

Multicellular organism, DNA in nucleus with chromosomes and membranes

Prokaryote

Single celled organism, distinct nucleus, no membrane

Monomer

A simple compound whose molecules can join together to form polymers

Building blocks of protein, carbs, nucleic acid and lipids

amino acid, simple sugars like glucose, fatty acid, glycerol

stem cell

unspecialized cell that can give rise to one or more types of specialized cells

How can stem cells be used in medicine?

To replace damaged tissues and cells

totipotent and example

meaning whole. Unlimited self renewal capabilities, can differentiate into any cell under appropriate condition. Like cell of embryo

Pluripotent cell and example

meaning many. Able to differentiate into any type of cell. Like blastocyst

Multi-potent cell and example

meaning several, able to limited range of cells. like foetal tissue.

Unipotent cell and example

Meaning one. Differentiate into one cell type, somatic cells, like neurons and muscle cels.

enzymes

Catalysts for chemical reactions in living things, speed up reactions. made of proteins

How enzymes work

they have an active site that connects to substrate, like a lock and key

simple diffusion

high to low concentrations, doesn't need energy (passive)

facilitated diffusion

high to low concentration, requires ATP (energy)

active transport

low concentration to high concentration, needs energy (active) moves against concentration gradient.

Osmosis

movement of solvent from a region of lower solute concentration through a semi-permeable membrane. No energy required (passive)

Isotonic

when the concentration of two solutions is the same

Hypotonic

Having a lower concentration of solute than another solution

Hypertonic

Having a higher concentration of solute than another solution.

Red Blood Cell when isotonic

normal state

RBC when hypotonic

diluted, swollen/turgid

RBC when hypertonic

Shrunken/Flaccid in concentrated solution

Endocytosis

entering the cell

exocytosis

exiting the cell

Phagocytosis

ingestion of bacteria, engulf large particles

Pinocytosis

Ingestion of liquids into the cell through the cell membrane, known as the "fluid endocytosis."

Phospholipids

controls what goes in an out of the cell as it has a selective. The fluid inside and outside is aqueous (water is solvent)

Diagram of a phospholipid

polar head is hydrophilic (attracted to water), two non polar tails are hydrophobic (repel water) which helps maintain homeostasis.

Plasma membrane parts

Peripheral proteins attach to chemical/integral proteins for cell communication. Carbohydrates identify the cell and act as binding site. Channel proteins are passageways from specific materials to go in and out of the cell. Cholesterol helps keep the membrane fluid by preventing the phospholipids from sticking, also adds rigidity so cell holds shape.

CNS

central nervous system; brain and spinal cord

PNS

Peripheral Nervous System, the sensory and motor neurons that connect the CNS to the rest of the body

Neurons

a cell that carries electrical signals around the body

Dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

Nucleus

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

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

myelin sheath

insulates the axon of some neurons and helps speed neural impulses

Axon

A threadlike extension of a neuron that transfers electrical signals

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended, where cellular reactions and processes occur

cell/plasma membrane

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

neurotransmitter

chemical messengers that cross the synaptic gaps between neurons

receptor

A small area on the dendrite that receives the signal from the other neuron

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

photosynthesis word formula

Carbon dioxide, water and light energy ---------> glucose and oxygen

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production, cellular respiration- Glucose + Oxygen = Carbon Dioxide and Water

immune system

protects the body from pathogens and diseases, fights an infection.

Pathogen

An organism that causes disease

two lines of defense

non-specific (physical/chemical barrier) like skin and mucus. Specific defense (immune response) Antigens, T and B cells

second line of defense

blood vessels dilate to allow WBC/phagocytes to enter infected tissue, infected tissue become red and swollen, fever may occur to kill pathogens.

Antigen

The substance that triggers an immune response

antibodies

Y-shaped proteins that attach to particular kinds of antigens, neutralising pathogens

B cells

Type of WBC that produces antibodies

Helper T cells

Activate Killer T cells and B cells

Cytoxic T cells

directly attacks pathogen that have invaded the inside of a cell

Phagocytes

engulf a pathogen and presents antigens on its surface, activating helper T cells

Memory B cells

Remain in body for years, produces more antibodies if your infected by the same pathogen again

Innate Immunity

Immunity you are born with, depends on genetic factors

Acquired Immunity

Life experience. Active or Passive

Active immunity

appears after exposure to pathogen. Memory B cells used providing long term immunity. Natural active immunity is exposure to the antigen or artificial is a vaccine.

Passive immunity

also called borrowed immunity. A person is given a medication that contains antibodies obtained from another person or animal. It has very fast acting but short lived, the body eventually destroys the foreign antibodies.

Different glands

Hypothalamus, pituitary, thyroid, adrenal, pancreas, testes/ovaries

Hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Target tissue

cells of an organ that are affected or stimulated by specific hormones

what do hormones control

growth, metabolism, reproduction, stress

pituitary gland

master gland, controls other endocrine glands

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

negative feedback

A primary mechanism of homeostasis, whereby a change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation.

positive feedback homeostasis

have a stimulus that causes a response to not solve but enhance it -- less common

negative feedback example

body temperature regulation

positive feedback example

childbirth and blood clotting

How body cools down

hypothalamus detects warmer blood, it then activates sweat glands, water evaporates and heat is lost, then temperature returns to normal

how body heats up

hypothalamus detects heat loss, activates muscles which shiver to generate heat, heat is gained and temperature returns to normal