B1 Flashcards
state functions of lysosomes
- destroy / digest old organelles, antigens, bacteria, pathogens
- break down worn out components of the cell, waste products, waste materials
state functions of the golgi apparatus
- modifies proteins and lipids and packages them in vesicles for transport
state functions of centrioles
- they help with cell division in animal cells
2. they make the spindle in cell division
state the function of the nucleus
- stores / contains cells DNA - genetic material which controls the activity of the cell
- it makes ribosomal subunits
state the function of the vesicle
- transports and stores substances in the cell
2. many vesicles cluster around the golgi apparatus
state the function of the nucleolus
- it makes ribosomes
2. to rewrite rRNA and combine it with proteins
state the function of the plasma membrane
- it protects the cell from it’s surroundings
2. it regulates movement of substances in and out of cells
state the function of rough endoplasmic rreticulum (rER)
- it is where proteins are made
state the function of smooth endoplasmic reticulum (sER)
- regulates and releases calcium ions and processes toxins.
2. where lipids are made
state the function of the mitochondria
- site of respiration
they are known as the powerhouse of the cell - where most reactions for aerobic respiration take place.
what is the function of cytoplasm
- where most chemical reactions happen
2. fluid that fills a cell
what is the function of ribosomes
- they are where proteins are made in the cell
what are eukaryotic cells?
state examples
eukaryotic cells contain organelles, these are structures with specialised functions often bound by a membrane.
examples: animal cells and plant cells
what are prokaryotic cells?
state examples
prokaryotes contain no membrane-bound organelles and are made of a single cell.
examples: bacteria,
what organelles do eukaryotes have?
- golgi apparatus
- lysosomes
- centrioles
- nucleus
- nucleolus
- vesicle
- plasma membrane
- rough ER
- smooth ER
- mitochondria
- cytoplasm
- ribosomes ( 80S)
what organelles do prokaryotes have?
- plasmids
- capsule
- ribosomes (70S)
- nucleoid
- cell wall
what is the function of plasmids
- they often contain additional genes that help the bacterium’s survival, such as antibiotic resistance or toxin producing genes.
what is the function of the capsule?
- it helps cells stick to surfaces
2. it protects cells from drying out, being engulfed or being engulfed such as by white blood cells
what is the function of ribosomes?
- they make proteins
what is the function of the nucleiod?
- it is the region where single circular, length of DNA is folded.
what is the function of the cell wall
- it gives the cell shape
structure of plasma membrane
consists of lipids and proteins
structure of rough ER
series of single, flattened sacs enclosed by a membrane
structure of smooth ER
series of single, tubular sacs made of membrane
structure of mitochondria
surrounded by a double membrane
contains 70S ribosomes and DNA
its central area contains a jelly called the matrix
structure of the golgi apparatus
a series of single, curved sacs enclosed by a membrane
many vesicles cluster around the golgi apparatus
structure of lysosome
it is enclosed by a single membrane
structure of centrioles
two hollow cylinders, found in pairs arranged at right angles to eachother
structure of the nucleolus
located inside the nucleus
isn’t surrounded by a membrane and sits in the nucleus.
structure of vesicles
small, membrane bound sac
structure of plasmids
double-stranded DNA in a circular structure
structure of a capsule
polysaccharide layer outside the cell wall
structure of the cell wall
it is made of long-chained molecule made up of a sugar and amino acids called peptidoglycan
plant cells include all the strucutres that are in animal cells apart from…
centrioles
structures in plant cells
- ribosome
- golgi apparatus,
- rough ER
- smooth ER
- plasma membrane
- mitochondrion
- nuclear envelope
- nucleolus
and - vacuole
- cell wall
- middle lamella
- plasmodesmata
- pit
- chloroplast
- amyloplast containing starch grains
- tonoplast membrane
what type of ribosomes do eukaroytes have?
80S
what type of ribosomes do prokaryotes have?
70S
what are chloroplasts
they work to convert light energy of the Sun into sugars that can be used by cells
they contain chlorophyll that absorb light needed for photosynthesis
what is a vacuole
it stores water and other substances
contains cell sap
what is a tonoplast membrane
it controls movement of molecules into and out of the vacuole
what is the cell wall
it supports and protects the cell and strengthens it
it is made of cellulose
what are amyloplasts
they store starch
they convert starch back into sugar when the plant needs energy.
what is the middle lamella
it sticks cell together
what is the plasmodesmata and pits
allow communication between one cell and another
what is photosynthesis
the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water
state similarities between plant and animal cells
Plant and animal cells both have ribosomes. both have: mitochondria ribosomes smooth and rough ER cytoplasm golgi apparatus
state differences between plant and animal cells
animal cells do not contain a cell wall
animal cells do not contain chloroplasts
plant cells do not contain lysosomes
plant cells do not contain centrioles
palisade cell
they are cylindrical shaped - they pack tightly in the upper part of a lea.
they contain many chloroplasts to capture as much energy from light as possible for photosynthesis
they have a large vacuole, which helps to keep the cell and leaf structure rigid
stuctures of a palisade cell
cell wall plasma membrane cytoplasm nucleus vacuole chloroplast
where are root hair cells found?
in the epithelium, near the root tip, where there is no epithelium
explain how root hair cells are adapted to their function
have a long cell extension into the soil increases the surface area for absorption of water and disolved minerals from the soil
thin cell wall makes it easier for substances to cross into the cell eg. water absorption
many mitochondria supply energy for active transport of minerals from the soil into the cell
what is the root hair cells function
absorbing water and disolved minerals
what is the main function of palisade mesophll cells?
to capture energy transferred by light
do gram-negative bacteria retain the gram stain (crystal violet) or not?
they DO NOT
do gram-positive bacteria retain the gram stain (crystal violet) or not
they DO
why do gram negative bacteria not retain the gram stain?
when gram negative bacteria is washed with acetone and absolute alcohol it doesn’t retain the gram stain because their cell wall has an outer layer
why do gram positive bacteria retain the gram stain?
gram positive retain the gram stain because their thick peptidoglycan wall absorbs the stain and they do not have a cell wall
which are more resistant to antibiotics? gram negative or gram positive and why?
gram negative are more resistant to antibiotics than gram positive bacteria, this is because gram negative bacteria have a cell wall with an outer membrane, which protects them from the antibiotic
what does gram negative bacteria have that gram positive bacteria doesn’t?
an outer cell membrane that surrounds the cell wall
what colour do gram negative bacteria turn?
turn pink by safranin
what colour do gram positive turn?
turn purple by crystal violet as they have a thick wall made of peptiglycan
examples of gram negative bacteria
e. coli
examples of gram positive bacteria
Staphylococcus
how do you work out the magnification?
size of image / size of real object
how many um (micrometre) in 1mm?
1000
