Grade 10 plant biology

Cytoplasm

Cytoplasm

Jelly-like substance within the cell membrane.

Lysosome

Sac filled with digestive chemicals.

Mitochondria

Structures that convert nutrients to energy.

Centriole

Structure that organizes motion of chromosomes.

Endoplasmic reticulum

Passageways where chemicals are made.

Vacuole

Sac that stores water, nutrients, or waste products.

Cell membrane

Membrane that surrounds and protects the cell.

Nucleus

Structure that contains DNA and regulates genes.

Cytoskeleton

Tubules and filaments that give the cell its shape.

Ribosome

Small structure that synthesizes proteins.

Nuclear membrane

Membrane that protects the nucleus.

Golgi apparatus

Stack of membranes that package chemicals.

Vesicle

Package created by the Golgi apparatus.

Nucleolus

Structure that manufactures ribosomes

Chloroplast

converts light energy into food by the process of photosynthesis

Vacuoles

Sacs that store water, food, and/or waste products. Larger than its counter part

Plastid

a group of materials, either synthetic or naturally occurring, that may be shaped when soft and then hardened to retain the given shape

Gene

A segment of DNA that codes for proteins.

3 main parts of a nucleotide

A phosphate group, sugar and a nitrogenous base

Complementary base pairs

Adenine always hydrogen bonds to Thymine

Cytosine bonds to Guanine

Chromosomes

Thread-like structures located inside the nucleus of animal and plant cells.

Mutation

A change in the DNA(Order of the A, C, T, G blocks) of an organism, it is a change to the base sequence.

Mutagen

Causes a mutation such as, examples are X-rays, UV rays

DNA screening

The process of testing individuals in a given population to identify those who have an increased risk of having or developing a particular genetic disorder or carrying a genetic variant for a particular disorder.

Transgenic Organism

An organism or cell whose genome has been altered by the introduction of one or more foreign DNA sequences from another species by artificial means.

Cloning

A number of different processes that can be used to produce genetically identical copies of a biological entity.

Nucleotide

The basic building block of RNA and DNA.

Diffusion

The passive movement of particles from a high concentration to a low concentration.

Equilibrium

An equal distribution of the particles

Semi-permeable

Some particles are allowed through the membrane, while others are not. It is permeable to some things.

Osmosis

The passive diffusion of water moving from an area of low solute concentration to high solute concentration

Solute and solvent

Sugar is a solute that can dissolve in water, which is a solvent.

Hypertonic

Having a higher osmotic pressure than a surrounding medium or a fluid under comparison

Hypotonic

Having a lower osmotic pressure than a surrounding medium or a fluid under comparison

chromatid

each of the two threadlike strands into which a chromosome divides longitudinally during cell division. Each contains a double helix of DNA.

Interphase

Divided into three stages : G1, S and G2.

G1 is the cell growth and development

S stage is the DNA contained in the cell’s chromatin that is duplicated

G2 is the synthesis of organelles.

Before Mitosis starts

Prophase

First phase of mitosis

Early _______ nucleolus disappears and chromatin condenses to form visible chromosomes.

Each chromosomes consists of two chromatids connected by a centromere

At the end of ________, the nuclear membrane dissolves away.

Metaphase

Second phase of mitosis

Centromeres of each chromosome are attached to spindle fibers.

Fibers change in length, pulling the chromosomes along a line on the equator of the cell.

Anaphase

Third phase of mitosis

Centromeres split

Sister chromatids are pulled to the opposite poles of the cell by spindle fibers

Phase ends when chromatids(now called daughter chromosomes) reach poles and stop moving

Telophase

Fourth and final phase of mitosis

Nuclear membrane forms around each set of daughter chromosomes and the nucleolus comes back in each nucleus

Daughter chromosomes unwind into chromatin

Cytokinesis

After mitosis

two identical nuclei are formed

sides of the cell pinch inward

Dividing the cytoplasm

forming two daughter cells

each containing copy of the parents cell DNA

Chromatin

A mixture of DNA and proteins that form the chromosomes found in the cells of humans and other higher organisms

G1 checkpoint

In the cell cycle, this checkpoint checks internal and external conditions. These conditions are:

• Size, is it big enough to divide?

• Nutrients, is there enough energy to divide?

• Molecular signals, any positive cues from neighbors

• DNA integrity, is any DNA damaged?

If all checks out the cells will enter the S phase and will be irreversibly committed to division. If not continued it will stay in a resting state called G0

G2 checkpoint

in the cell cycle, This checkpoint checks the:

• DNA integrity, is there any DNA damaged?

• DNA replication, was all the DNA completely copied during S phase?

If there is any damage the cell will pause at the ____ checkpoint to allow repairs.

Spindle checkpoint

In the cell cycle, this checkpoints checks the cell and examines whether all the sister chromatids are correctly attached to the spindle microtubules.

This checkpoint does not scan the metaphase plate to confirm all chromosomes are there. It actually looks for “straggler” chromosomes. If one is found the cell will pause mitosis allowing the _______ to capture the stray chromosome.

Apoptosis

The programmed death of a cell that occurs as a normal and controlled part of an organism's growth or development.

3 different consequences of mutations

Mutations can be beneficial, harmful, or neutral.

Metastasis

When tumor cells break off from the original tumor and start growing at a different part of the body.

tumor

A swelling of a part of the body, generally without inflammation, caused by an abnormal growth of tissue, whether benign or malignant.

Mitosis, DNA

Cancer is broken ___ or even more specifically, _ replication.

Cell specialization

The process by which cells develops from similar cells into cells that have a specific functions within a multicellular organism

Cell differentiation

A stage of development of a living organisms during which specialized cells forms

Meristematic cells

Responsible for growth. These are undifferentiated cells that can form specialized cells in plants

Dermal tissue

Covers the outside of a plant in a single layer of cells called the epidermis.

Epidermis

• Critical for exchange of gases

• Guard cells- control the open and close of stomata

• These cells secrete a waxy substance called cuticle.

Cuticle

A waxy substance that coats, waterproofs, and protects the above-ground parts of plants. _______ helps prevent water loss, abrasions, infections, and damage from toxins.

Ground tissue

Makes up much of the interior of a plant and carries out basic metabolic functions. _____ ____ in stems provides support and may store food or water. ____________ in roots may also store food.

Vascular Tissue

Runs through the ground tissue inside a plant. The transport of water and dissolved substances inside the plant

Xylem

Tissue that takes care of moving water and minerals from the roots to other plant parts, including leaves, where these materials are needed for photosynthesis. Is hollow to allow for quick transport - Fortified with lignin

Phloem

Tissue that moves the sugars produced by photosynthesis to other plant parts. Is made up of vertically stacked tubes, cell walls are porous allowing for exchange of materials.

Leaf

#1 job is photosynthesis and to store sugar in the form of starch

Upper leaf

Epidermis secretes a waxy cuticle (protects leaf) , stops water evaporation

Mesophyll (middle leaf)

Palisade tissue cells perform photosynthesis, active (lots of mitochondria)

• Contain chloroplasts for photosynthesis

• contain the pigment chlorophyll

• contain disks called thylakoids (in grana) which absorbs light energy which is used to produce glucose

• glucose is a carbohydrate used by both plants and animals for energy

Parenchyma

loosely organized for spaces where gas may be exchanged

Lower leaf

Epidermis -

• critical for exchange of gases

• Guard cells- control the open and close of stomata

Stem

Two main functions

• support and transportation (water and nutrients)

• Has Xylem and Phloem within

Roots

• anchor plant and take up water

• ____ hairs are the main site for water and mineral absorption

• can store sugar (eg. beets)

• pericycle- layer of tissue that surrounds xylem and phloem and gives rise to branch _____

Flower

• reproductive organ

• different parts of the ______are specialized leaves that produce pollen (sperm), and eggs

• produces seeds which are embedded in fruits

• Pollination: facilitated by wind & animals

Root system

Consists of all the _____ that lie below the surface. As well as responsible for taking in water and minerals from the soil. Constantly growing to keep up the pace with plants demand for more nutrients as it also grows

Shoot system

Everything else (organs) above the ground for a plant. It is responsible for supporting the plant, performing photosynthesis, transporting water, nutrients and sugars

Effect of root pressure on water movement

• As root cells bring minerals into the xylem , the mineral concentration in the xylem increases.

• The high concentration of minerals increases the tendency of water to diffuse (osmosis) into the root xylem

• Root pressure , transpiration and some unique properties of water molecules force sap up the tree

Transpiration

1. Water from the soil enters the xylem in the roots; tension in the water column extends from the leaves to the roots

2. The water column is held together by cohesion; adhesion keeps the water column in place

3. ______________ ( evaporation) of water from the leaves creates tension that pulls on the water column in the place

Transpiration is controlled by

• The amount of water vapor in the leaves

• When the amount of water vapor is large, the guard cells open stomata and water vapor moves out of the leaves

• If the amount of water vapor is small, the guard cells relax and the stomata is closed

Glucose Transport

• Once photosynthesis has occurred, glucose will either be used or is converted into sucrose and other carbohydrates

• Sucrose that makes its way to the roots is usually chemically changed to starch

• Starch is not soluble in water, so must be first converted to sucrose, which then dissolves in water and is transported again as sap

• In spring, trees need to nourish the many buds

• The sap that flows upward from the roots through phloem contains large amounts of sucrose and moves to where it is needed

• Once the leaves have grown they can then make their own glucose through photosynthesis

• Extra glucose produced during the summer and fall is transport to other plant tissue or stored in the roots as starch (and the whole process repeated)