final lab practical study

homeostasis

the process by which living organisms maintain a stable internal environment despite changes inside or outside the body

receptor

detects a change in the environment

control center

receives information and decides how to respond

effector

carries out the response to correct the change

negative feedback

reverses/reduces a change to bring conditions back to normal

positive feedback

amplifies or increases a change instead of reversing it

integumentary system

regulates temperature

cardiovascular system

regulates blood flow and pressure

respiratory system

inhales oxygen and exhales CO2

reproductive system

produces gametes & hormones

nervous system

detects changes and sends rapid signals to maintain balance

gastrointestinal system

breaks down food and absorbs them into nutrients

lymphatic/immune system

returns excess fluid to bloodstream

urinary system

regulates water and pH balance

skeletal system

stores minerals

muscular system

helps maintain body temperature

fertilization

the union of a sperm cell and an egg cell to form a zygote

cleavage

a series of rapit mitotic cell divisions that increases the number of cells without increasing overall size of embryo

gastrulation

the process by which the embryo reorganizes into three primary germ layers [ectoderm, mesoderm, endoderm]

ectoderm

skin and nervous system

mesoderm

muscles, bones, circulatory system

endoderm

digestive and respiratory linings

organogenesis

the stage during which the germ layers develop into specific organs and organ systems

tissue specialization

the process where cells become structurally and functionally specialized for particular roles

development sequence

fertilization, cleavage, gastrulation, organogenesis, tissue specialization

mitosis

cell division that produces two identical diploid daughter cells used for growth and repair [location: onion root tip]

meiosis

cell division that produces four genetically different haploid cells (gametes)

homozygous recessive

two identical, recessive alleles for a specific gene (aa)

homozygous dominant

two identical dominant alleles for a specific gene (AA)

heterozygous

two different alleles of a specific gene, one inherited from each biological parent (Aa)

phenotype

the set of observable characteristics, traits, or physical appearance of an organism (ex: hair color, eye color)

genotype

the specific set of genes an organism inherits (ex: aa, AA, Aa)

alleles

a variant form of a specific gene, representing different versions of a DNA sequence at a given genomic location

chromosomes

a thread-like structure located inside the nucleus of animal and plant cells, composed of a single, long molecule of DNA coiled tightly around proteins

stages of mitosis order

prophase → metaphase → anaphase → telophase

prophase

nucleus is still present; chromosomes are condensing

metaphase

chromosomes line up in the middle of the cell; nucleus becomes disassembled

anaphase

chromosomes move away to the opposite sides of the cell, towards the poles of the cells

telophase

chromosomes are at the opposite ends and new nuclei are are forming on each side to make new cells

cytokinesis

the final physical process of cell division, where the cytoplasm of a single eukaryotic cell divides into two distinct daughter cells

meiosis stages of division

Meiosis 1: prophase I → metaphase I → anaphase I → telophase I / Meiosis II: prophase II → metaphase II → anaphase II → telophase II

prophase I

chromosomes condense and thicken; homologous chromosomes cross over and exchange genetic info between each other

metaphase I

chromosomes are at the middle of the cell

Anaphase I

chromosomes are pulled away by spindle fibers

Telophase I

two newly formed nuclei

Prophase II

spindles start to form, but not as eventful as its stage 1

Metaphase II

chromosomes are in the middle in a single file line

Anaphase II

chromatids are getting pulled away by spindle fibers

Telophase II

nuclei reforms and 4 cells are formed