cellular biology Flashcards
unit 1
what are these three ideas referred to as;
(1) all living things are made up of one or more cells and their products
(2) the cell is the simplest unit that can carry out all life processes
(3) all cells come from other cells; they do not come from non-living matter
these are the the three ideas in which biology is built on, referred as the “cell theory”
what are all living things made up of?
cells!
simplest organisms have…
no nucleus or other organelles (cell with no nucleus if referred to as prokaryote)
2 examples of simplest organisms:
archaea & bacteria
complex organisms have…
a nucleus and other organelles (known as eukaryotes)
2 examples of more complex organisms:
protists and fungi
ORRR
animals and plants
what is an organelle?
a structure that carries out a specific function for the cell
name the 11 organelles of the cell:
- Golgi apparatus
- Cell membrane
- Smooth endoplasmic reticulum
- Rough endoplasmic reticulum
- Lysosomes
- Vacuole
- Centriole
- Ribosomes
- Cytoskeleton
- Nucleus
11.Mitochondria
what 6 basic activities does every cell preform to stay alive?
- use energy
- store materials
- take materials from the environment
- get rid of wastes
- moves substances to where they are needed
- reproduce
organelles of a cell ___________
work together
_______ and ____________ have many of the same organelles but there are some differences
plant and animal cells
what are differences between plant and animal cells?
plant cells = one singular large vacuole, have a cell wall, have chloroplasts, rectangular or cubic in shape
animal cells = smaller vacuoles but many, typically round or irregular in shape
how many micrometers in length are animal and plant cells?
animal = 10-30 micrometers
plant = 10-100 micrometers
what is cytoplasm?
the substance inside the cell which the organelles are suspended in
(mostly water)
(allows organelles to move around)
what is the cell membrane?
surrounds the cell (double layered), supporting and allowing the cell to enter while keeping others out (semi permeable membrane)
define the nucleus
nucleus = control center of the cell
contains genetic information aka DNA which is stored in chromosomes
what does DNA carry?
DNA (deoxyribonucleic acid) Carrie’s coded instructions
- for ALL cell activity
- during cell division the DNA is copied giving each new cell a complete set of chromosomes
what is the mitochondria also known as?
mitochondrion
define mitochondrion:
“power plants” of the cell
- cells store energy as a form of glucose (sugar)
active cells vs less active cells
active = more mitochondria (ex. muscle)
less = less mitochondria
(ex. fat-storage cells)
what do mitochondrial enzymes do?
mitochondrial enzymes make energy available in a form that can be used (cellular respiration)
2 examples of cellular respiration:
- glucose + oxygen
-carbon dioxide + water + energy
define the endoplasmic reticulum:
also known as the highway of the cell
- fluid filled tubes transport material throughout the cell
what does the role of endoplasmic reticulum play regarding the brain and muscle?
- it allows the production and release of hormones in the brain
- and allows muscle contraction
what do Golgi bodies do?
- collect & process materials to be removed from the cell
- make and secrete mucus
define the vacuole:
a storage container for food, water, waste, wastes, etc.
functions vary on the cell type.
define a cell wall:
Provides support and protection for the cell
define chloroplasts:
contain chlorophyll & gives leaves their green colour
what do chloroplasts absorb and why?
they absorb light energy to be used in photosynthesis
what’s the purpose of photosynthesis?
allows plants to gain energy from the sun so they can make their own food
- carbon dioxide + water + energy (sunlight)
what do ribosomes do?
make proteins for the cell
what is the purpose of lysosomes?
known as the garbage man of the cell lysosomes get rid of waste materials
what is the purpose of the cytoskeleton?
helps maintain the cells shape and provides support
functions of the cell membrane:
-allows a steady supply of nutrients to enter cells
-can remove excess nutrients and wastes
-helps maintain homeostasis
what does semi-permeable allow?
allows some molecules into cell while keeping others out
Phospholipids move within the membrane like _____
water
Membrane is _____
flexible
_________ within membrane create a pattern on the membrane surface
proteins
Contain proteins called _______ proteins that help regulate what can enter and leave a cell
transport
what is diffusion?
-the random movement of particles from an area of HIGHER concentration (NO ENERGY is required)
Speed of diffusion is affected by:
- concentration of the solution
- temperature
- pressure
what is osmosis
the diffusion water
- high concentration > low
what is concentration gradient
the unequal distribution of particles
OR
the difference in concentration of a substance across a membrane
what is isotonic?
Amount of water transported into the cell concentration inside the cell is EQUAL to outside
hypotonic shown in plants vs animals
plants = causes cell to become rigid
animals = increase in pressure causes animal cells to swell and burst
hypotonic means what?
there is a high concentration of water OUTSIDE cell, causing water to move inside the cell (osmosis)
what does hypertonic mean?
concentration of dissolved substances is greater on the outside of cell
what are the three types of solutions?
- isotonic
- hypotonic
- hypertonic
what is passive transport?
transport which uses no energy to move particles across membrane
what are channel proteins?
channels that allow molecules such as; ions and small dissolved particles to flow
role of carrier proteins:
changes shape to allow substance through
what are the three characteristics of a stem cell?
- dividing for long periods of time
- refraining from being specialized
- having plasticity
what is the ethical controversy over using human embryonic stem cells for research?
due to the process of harvesting embryos (It is argued that using and destroying embryos shows a lack of respect for the value and dignity of life)
how are embryos obtained?
embryonic stem cells are obtained from early embryos, as only four days after fertilization, the cells divide into a blastocyst with two cell layers, making the cells no longer totipotent
totipotent vs pluripotent stem cell
totipotent = lose the ability to form an entire individual
pluripotent = can form one
pluripotent vs multipotent stem cell
pluripotent = less limited
multipotent = can develop into more than one cell type
what do IPSCs stand for?
induced-pluripotent stem cells
role of IPSCs:
formed by adult somatic cells to replace pluripotent embryonic stem cells
what are two potential uses of using IPSCs?
- safe and more reliable drug testing
- removing the risk of immune system rejection
What is Metabolism a word for
A word for all of the chemical reactions that happen in the body
Name two related terms to metabolism
Chemical reaction/homeostasis
What is a mutation?
An event that changes an organism’s DNA
What is a nutrient
A nutrient is any molecule that nourishes an organism
What do nutrients provide resources for?
-growth
-survival
-production
what are the 3 main types of nutrients?
- carbohydrates
- lipids
- proteins
What is the optimal pH range
the range of pHs at which an enzyme works best (Small changes in pH can change the shape of an enzyme and prevent it from working)
What is the pancreas?
an organ that produces digestive enzymes and releases them into the small intestine
What is Pepsin
an enzyme that is released by cells in the lining of the stomach. Pepsin breaks down protein
What is pH?
A measurement of how basic or acidic a solution or environment is.
Low pH vs High pH
The lower the pH, the more acidic the environment. The higher the pH, the more basic the environment.
what is a protease
an enzyme that breaks down proteins. (one of the enzymes that breaks down food in the small intestine.)
What are proteins
large molecules that do most of the work in a cell
roles of protein
-signaling
-substance transport
-speeding up chemical reactions
what are the two types of metabolism reactions
- breaking things down (food)
- building things up (muscle)
How do enzymes and catalysts connect
Enzymes are a type of catalyst. All enzymes are catalysts, but not all catalysts are enzymes.
T or F does every enzyme have an active site
True
T or F an enzyme can catalyze most reactions if the reactants are at a high concentration
False
T or F an enzyme’s active site is determined by the shape of the enzyme
True
T or F enzymes speed up reaction rates
True
Enzymes in the stomach:
Pepsin (breaks down proteins 7 requires low pH)
Enzymes in the small intestine:
Protease (Breaks down proteins)
Lipase (Breaks down lipids fats)
Carbohydrase (Breaks down carbohydrates)
Describe the motion of the gas particles.
Fast-moving/in constant motion
