B1-B4 Flashcards
(39 cards)
Define: movement
An action by an organism or part of an organism causing a change of position or place
Define respiration
the chemical reactions in cells that break down nutrient molecules and release energy for metabolism
Define sensitivity
the ability to detect or sense stimuli in the internal or external environment and to make appropriate responses
Define growth
a permanent increase in size and dry mass by an increase in cell number or cell size or both
Define reproduction
the processes that make more of the same kind of organism
Define excretion
removal from organisms of the waste products of metabolism (chemical reactions in cells including respiration), toxic materials, and substances in excess of requirements
Define nutrition
taking in of materials for energy, growth and development; plants require light, carbon dioxide, water and ions; animals need organic compounds and ions and usually water
What are all living organisms made of?
Unicellular organisms, such as bacteria consist of a single cell
Multicellular organisms consist of many cells
Ex: humans = approximately 50 trillion cells
Draw and label the parts of a plant cell
Cellulose cell wall
Cell membrane
Nucleus
Cytoplasm
Motichondrion
Permanent vacuole
Chloroplast
Draw and label the parts of an animal cell
Cytoplasm
Nucleus
Cell membrane
Mitochondrion
Compare plant and animals cells
Plant cells -> cellulose cell wall outside the cell membrane
Animal cells -> no cell wall
Plant cells -> chloroplast (with chlorophyll)
Animal cells -> no chloroplast
Plant cells -> large vacuoles with cell sap
Animal cells -> small vacuoles
Plant cells -> starch grains
Animal cells -> no starch grains, sometimes glycogen granules
Plant cells -> regular shape
Animal cells -> irregular shape
What are the functions of the parts of the cell and animal cells?
Cell membrane:
Thin layer of protein and fat
Controls what goes in and out of cells
Partially permeable
Cell wall:
Plant cells only
Mainly cellulose (crisscrossed -> strong covering)
Protects and supports cells (no burst)
Fully permeable
Cytoplasm:
Clear jelly (around 70% water)
Many substances dissolved in it -> proteins
Different metabolic processes happen here
Vacuoles:
Space in a cell surround by a membrane, contain a solution
presses out -> keep cell shape
Plant cells -> large and permanent (solution of sugars + other = cell sap)
Animals cells -> smaller
Chloroplast:
Only in plants -> the green pigment (chlorophyll) -> photosynthesis
Often has starch
Nucleus:
Genetic information -> chromosomes -> DNA
What is the location and functions of these cells:
Ciliated cells
Root hair cells
Palisade mesophyll cells
Red blood cells
Sperm and egg cells
ciliated cells – in the trachea and bronchi →movement of mucus (carried bad bacteria and goes to stomach where acid destroys)
root hair cells – near the ends of plants roots → absorption
palisade mesophyll cells – beneath the epidermis of the leaf → photosynthesis
red blood cells – in mammal blood → transport of oxygen
sperm and egg cells – in testes and ovaries → reproduction
How is magnification calculated (formula)?
Magnification= size of image/size of real object
Define diffusion
Movement of particles from an area of higher concentration to an area of lower concentration down a concentration gradient as a result of their random movement
Passive processes -> no energy required
Diffuse until equilibrium is reached
What are factors that influence diffusion?
Surface area:
Surface area of membrane increase, rate of diffusion increases
More space for molecules to diffuse
Concentration:
Greater the concentration gradient, quicker the diffusion
Greater difference in concentrations
Temperature:
Temp increases, diffusion increases
Particles gain kinetic energy -> diffuse more quickly
Distance:
Shorter distance, faster diffusion
Substance travels less
What quality does the membrane have to have to allow diffusion?
It is partially permeable
Define osmosis
Movement of water molecules from region of higher water potential to region of lower water potential through a permeable membrane
What is the effect on plant tissue if it is immersed into solutions of different concentration?
Low concentration solution (high water potential):
Solution in cell more concentrated than outside cell
Water diffuses for equilibrium
Vacuole is full -> pressing up against cell membrane+wall -> cell is turgid (as it should be)
Equal concentration solution (equilibrium):
Solution outside and inside cell have equal concentration
Cell is flaccid -> plant begins to wilt
High concentration solution (low water potential):
Solution inside cell less concentrated than outside cell
Water diffuses out for equilibrium -> cytoplasm and vacuole shrink -> cell wall left as cytoplasm pulls away -> cell wall is plasmolysed (plasmolysis)
What process is necessary for the uptake of water in plants?
Osmosis
Soil has water -> water diffused through the cell membranes of root hair cells -> into plant -> photosynthesis + retain turgidity
What is the effect on animal cells if it is immersed into solutions of different concentration?
Low concentration solution:
Solution outside is less concentrated than inside
Water diffuses in -> no cell wall -> cell ruptures due to excess water -> lysis
Equal concentration solution:
Normal
High concentration solution:
Solution outside is more concentrated than inside
Water diffuses out -> cytoplasm shrinks -> whole cell shrivels -> crenation
What is are the chemical elements in carbohydrates?
Carbon, hydrogen and oxygen
What are carbohydrates? (+bond type)
Long chains of simples sugars
Glucose -> simple sugar (monosaccharide -> soluble in water)
2 glucose -> maltose (disaccharide -> soluble in water)
Lots of glucose -> starch, glycogen, cellulose (poly saccharide -> insoluble in water)
Carbohydrates bonds -> glycosidic bonds
What is the used of carbohydrates?
Easily available energy
Release energy into cells -> respiration
Glucose travels to cells to release energy for metabolic reactions
Storage as starch in plants + cellulose fibers in plant walls
